added copyright header

[taylor/freespace2.git] / src / ship / shipfx.cpp

/*
 * Copyright (C) Volition, Inc. 1999.  All rights reserved.
 *
 * All source code herein is the property of Volition, Inc. You may not sell 
 * or otherwise commercially exploit the source or things you created based on
 * the source.
 */

/*
 * $Logfile: /Freespace2/code/Ship/ShipFX.cpp $
 * $Revision$
 * $Date$
 * $Author$
 *
 * Routines for ship effects (as in special)
 *
 * $Log$
 * Revision 1.3  2002/06/09 04:41:26  relnev
 * added copyright header
 *
 * Revision 1.2  2002/05/07 03:16:52  theoddone33
 * The Great Newline Fix
 *
 * Revision 1.1.1.1  2002/05/03 03:28:10  root
 * Initial import.
 *
 * 
 * 51    9/13/99 4:53p Andsager
 * 
 * 50    9/13/99 10:09a Andsager
 * Add debug console commands to lower model render detail and fireball
 * LOD for big ship explosiosns.
 * 
 * 49    9/08/99 10:44p Andsager
 * Make HUGE ships not die when warping out, after warp effect started.
 * 
 * 48    9/06/99 10:16p Andsager
 * Modify big ship explosions.  Less frequent fireballs, fewer particles,
 * larger fireballs
 * 
 * 47    9/05/99 11:10a Andsager
 * Fix up which split ship get debris pieces.  Dont render debris pieces
 * for split ships until they are near clip plane.
 * 
 * 46    9/02/99 12:55a Mikek
 * Scale engine wash by speed.
 * 
 * 45    9/01/99 10:15a Dave
 * 
 * 44    8/31/99 10:13p Andsager
 * Add Knossos warp effect fireball
 * 
 * 43    8/23/99 11:09a Andsager
 * Round 2 of Knossos explosion
 * 
 * 42    8/20/99 2:16p Andsager
 * Make only supercaps slow down extra fast after warping in.
 * 
 * 41    8/20/99 1:42p Andsager
 * Frist pass on Knossos explosion.
 * 
 * 40    8/19/99 4:36p Andsager
 * Cleaned up special_warpout
 * 
 * 39    8/16/99 10:04p Andsager
 * Add special-warp-dist and special-warpout-name sexp for Knossos device
 * warpout.
 * 
 * 38    8/16/99 2:01p Andsager
 * Knossos warp-in warp-out.
 * 
 * 37    8/13/99 10:49a Andsager
 * Knossos and HUGE ship warp out.  HUGE ship warp in.  Stealth search
 * modes dont collide big ships.
 * 
 * 36    8/05/99 2:06a Dave
 * Whee.
 * 
 * 35    7/18/99 12:32p Dave
 * Randomly oriented shockwaves.
 * 
 * 34    7/09/99 12:52a Andsager
 * Modify engine wash (1) less damage (2) only at a closer range (3) no
 * damage when engine is disabled
 * 
 * 33    7/06/99 10:45a Andsager
 * Modify engine wash to work on any ship that is not small.  Add AWACS
 * ask for help.
 * 
 * 32    7/02/99 9:55p Dave
 * Player engine wash sound.
 * 
 * 31    7/02/99 4:31p Dave
 * Much more sophisticated lightning support.
 * 
 * 30    7/01/99 4:23p Dave
 * Full support for multiple linked ambient engine sounds. Added "big
 * damage" flag.
 * 
 * 29    7/01/99 11:44a Dave
 * Updated object sound system to allow multiple obj sounds per ship.
 * Added hit-by-beam sound. Added killed by beam sound.
 * 
 * 28    6/17/99 12:06p Andsager
 * Add a fireball for each live debris piece.
 * 
 * 27    6/14/99 3:21p Andsager
 * Allow collisions between ship and its debris.  Fix up collision pairs
 * when large ship is warping out.
 * 
 * 26    5/27/99 12:14p Andsager
 * Some fixes for live debris when more than one subsys on ship with live
 * debris.  Set subsys strength (when 0) blows off subsystem.
 * sexp_hits_left_subsystem works for SUBSYSTEM_UNKNOWN.
 * 
 * 25    5/26/99 11:46a Dave
 * Added ship-blasting lighting and made the randomization of lighting
 * much more customizable.
 * 
 * 24    5/25/99 10:05a Andsager
 * Fix assert with wing warping out with no warp effect.
 * 
 * 23    5/24/99 5:45p Dave
 * Added detail levels to the nebula, with a decent speedup. Split nebula
 * lightning into its own section.
 * 
 * 22    5/21/99 5:03p Andsager
 * Add code to display engine wash death.  Modify ship_kill_packet
 * 
 * 21    5/19/99 11:09a Andsager
 * Turn on engine wash.  Check every 1/4 sec.
 * 
 * 20    5/18/99 1:30p Dave
 * Added muzzle flash table stuff.
 * 
 * 19    5/17/99 10:33a Dave
 * Fixed warning.
 * 
 * 18    5/11/99 10:16p Andsager
 * First pass on engine wash effect.  Rotation (control input), damage,
 * shake.  
 * 
 * 17    5/09/99 6:00p Dave
 * Lots of cool new effects. E3 build tweaks.
 * 
 * 16    4/28/99 11:13p Dave
 * Temporary checkin of artillery code.
 * 
 * 15    3/29/99 6:17p Dave
 * More work on demo system. Got just about everything in except for
 * blowing ships up, secondary weapons and player death/warpout.
 * 
 * 14    3/28/99 5:58p Dave
 * Added early demo code. Make objects move. Nice and framerate
 * independant, but not much else. Don't use yet unless you're me :)
 * 
 * 13    3/23/99 2:29p Andsager
 * Fix shockwaves for kamikazi and Fred defined.  Collect together
 * shockwave_create_info struct.
 * 
 * 12    3/20/99 3:03p Andsager
 * Fix get_model_cross_section_at_z() from getting invalid index .
 * 
 * 11    3/19/99 9:51a Dave
 * Checkin to repair massive source safe crash. Also added support for
 * pof-style nebulae, and some new weapons code.
 * 
 * 10    2/26/99 4:14p Dave
 * Put in the ability to have multiple shockwaves for ships.
 * 
 * 9     1/29/99 12:47a Dave
 * Put in sounds for beam weapon. A bunch of interface screens (tech
 * database stuff).
 * 
 * 8     1/28/99 9:10a Andsager
 * Particles increased in width, life, number.  Max particles increased
 * 
 * 7     1/27/99 9:56a Dave
 * Temporary checkin of beam weapons for Dan to make cool sounds.
 * 
 * 6     1/11/99 12:42p Andsager
 * Add live debris - debris which is created from a destroyed subsystem,
 * when the ship is still alive
 * 
 * 5     11/18/98 10:29a Johnson
 * fix assert in shipfx_remove_submodel_ship_sparks.  submodel may not
 * have spark and be destroyed.
 * 
 * 4     11/17/98 4:27p Andsager
 * Stop sparks from emitting from destroyed subobjects
 * 
 * 3     10/20/98 1:39p Andsager
 * Make so sparks follow animated ship submodels.  Modify
 * ship_weapon_do_hit_stuff() and ship_apply_local_damage() to add
 * submodel_num.  Add submodel_num to multiplayer hit packet.
 * 
 * 2     10/07/98 10:53a Dave
 * Initial checkin.
 * 
 * 1     10/07/98 10:51a Dave
 * 
 *
 * $NoKeywords: $
 */

#include "pstypes.h"
#include "systemvars.h"
#include "ship.h"
#include "fireballs.h"
#include "debris.h"
#include "hudtarget.h"
#include "shipfx.h"
#include "multi.h"
#include "gamesnd.h"
#include "timer.h"
#include "3d.h"                 // needed for View_position, which is used when playing a 3D sound
#include "multi.h"
#include "multiutil.h"
#include "hud.h"
#include "fvi.h"
#include "gamesequence.h"
#include "lighting.h"
#include "linklist.h"
#include "particle.h"
#include "multimsgs.h"
#include "multiutil.h"
#include "bmpman.h"
#include "freespace.h"
#include "muzzleflash.h"
#include "demo.h"
#include "shiphit.h"
#include "neblightning.h"
#include "objectsnd.h"

#ifndef NDEBUG
extern float flFrametime;
extern int Framecount;
#endif

#define SHIP_CANNON_BITMAP                      "argh"
int Ship_cannon_bitmap = -1;

int Player_engine_wash_loop = -1;

void shipfx_remove_submodel_ship_sparks(ship *shipp, int submodel_num)
{
        Assert(submodel_num != -1);

        // maybe no active sparks on submodel
        if (shipp->num_hits == 0) {
                return;
        }
        
        for (int spark_num=0; spark_num<shipp->num_hits; spark_num++) {
                if (shipp->sparks[spark_num].submodel_num == submodel_num) {
                        shipp->sparks[spark_num].end_time = timestamp(1);
                }
        }
}

// Check if subsystem has live debris and create
// DKA: 5/26/99 make velocity of debris scale according to size of debris subobject (at least for large subobjects)
void shipfx_subsystem_mabye_create_live_debris(object *ship_obj, ship *ship_p, ship_subsys *subsys, vector *exp_center, float exp_mag)
{
        // initializations
        polymodel *pm = model_get(ship_p->modelnum);
        int submodel_num = subsys->system_info->subobj_num;
        submodel_instance_info *sii = &subsys->submodel_info_1;

        object *live_debris_obj;
        int i, num_live_debris, live_debris_submodel;

        // get number of live debris objects to create
        num_live_debris = pm->submodel[submodel_num].num_live_debris;
        if (num_live_debris <= 0) {
                return;
        }

        ship_model_start(ship_obj);

        // copy angles
        angles copy_angs = pm->submodel[submodel_num].angs;
        angles zero_angs = {0.0f, 0.0f, 0.0f};

        // make sure the axis point is set
        if ( !sii->axis_set ) {
                model_init_submodel_axis_pt(sii, ship_p->modelnum, submodel_num);
        }

        // get the rotvel
        vector model_axis, world_axis, rotvel, world_axis_pt;
        void model_get_rotating_submodel_axis(vector *model_axis, vector *world_axis, int modelnum, int submodel_num, object *obj);
        model_get_rotating_submodel_axis(&model_axis, &world_axis, ship_p->modelnum, submodel_num, ship_obj);
        vm_vec_copy_scale(&rotvel, &world_axis, sii->cur_turn_rate);

        model_find_world_point(&world_axis_pt, &sii->pt_on_axis, ship_p->modelnum, submodel_num, &ship_obj->orient, &ship_obj->pos);

        matrix m_rot;   // rotation for debris orient about axis
        vm_quaternion_rotate(&m_rot, vm_vec_mag((vector*)&sii->angs), &model_axis);


        // create live debris pieces
        for (i=0; i<num_live_debris; i++) {
                live_debris_submodel = pm->submodel[submodel_num].live_debris[i];
                vector start_world_pos, start_model_pos, end_world_pos;

                // get start world pos
                vm_vec_zero(&start_world_pos);
                model_find_world_point(&start_world_pos, &pm->submodel[live_debris_submodel].offset, ship_p->modelnum, live_debris_submodel, &ship_obj->orient, &ship_obj->pos );

                // convert to model coord of underlying submodel
                // set angle to zero
                pm->submodel[submodel_num].angs = zero_angs;
                world_find_model_point(&start_model_pos, &start_world_pos, pm, submodel_num, &ship_obj->orient, &ship_obj->pos);

                // rotate from submodel coord to world coords
                // reset angle to current angle
                pm->submodel[submodel_num].angs = copy_angs;
                model_find_world_point(&end_world_pos, &start_model_pos, ship_p->modelnum, submodel_num, &ship_obj->orient, &ship_obj->pos);

                // create fireball here.
                fireball_create(&end_world_pos, FIREBALL_EXPLOSION_MEDIUM, OBJ_INDEX(ship_obj), pm->submodel[live_debris_submodel].rad);

                // create debris
                live_debris_obj = debris_create(ship_obj, ship_p->modelnum, live_debris_submodel, &end_world_pos, exp_center, 1, exp_mag);

                // only do if debris is created
                if (live_debris_obj) {
                        // get radial velocity of debris
                        vector delta_x, radial_vel;
                        vm_vec_sub(&delta_x, &end_world_pos, &world_axis_pt);
                        vm_vec_crossprod(&radial_vel, &rotvel, &delta_x);

                        if (Ship_info[ship_p->ship_info_index].flags & SIF_KNOSSOS_DEVICE) {
                                // set velocity to cross center of knossos device
                                vector rand_vec, vec_to_center;

                                float vel_mag = vm_vec_mag_quick(&radial_vel) * 1.3f * (0.9f + 0.2f*frand());
                                vm_vec_normalized_dir(&vec_to_center, &world_axis_pt, &end_world_pos);
                                vm_vec_rand_vec_quick(&rand_vec);
                                vm_vec_scale_add2(&vec_to_center, &rand_vec, 0.2f);
                                vm_vec_scale_add2(&live_debris_obj->phys_info.vel, &vec_to_center, vel_mag);

                        } else {
                                // Get rotation of debris object
                                matrix copy = live_debris_obj->orient;
                                vm_matrix_x_matrix(&live_debris_obj->orient, &copy, &m_rot);

                                // Add radial velocity (at least as large as exp velocity)
                                vector temp_vel;        // explosion velocity with ship_obj velocity removed
                                vm_vec_sub(&temp_vel, &live_debris_obj->phys_info.vel, &ship_obj->phys_info.vel);

                                // find magnitudes of radial and temp velocity
                                float vel_mag = vm_vec_mag(&temp_vel);
                                float rotvel_mag = vm_vec_mag(&radial_vel);

                                if (rotvel_mag > 0.1) {
                                        float scale = (1.2f + 0.2f * frand()) * vel_mag / rotvel_mag;
                                        // always add *at least* rotvel
                                        if (scale < 1) {
                                                scale = 1.0f;
                                        }

                                        if (exp_mag > 1) {      // whole ship going down
                                                scale = exp_mag;
                                        }

                                        if (Ship_info[ship_p->ship_info_index].flags & SIF_KNOSSOS_DEVICE) {
                                                scale = 1.0f;
                                        }

                                        vm_vec_scale_add2(&live_debris_obj->phys_info.vel, &radial_vel, scale);
                                }

                                // scale up speed of debris if ship_obj > 125, but not for knossos
                                if (ship_obj->radius > 250 && !(Ship_info[ship_p->ship_info_index].flags & SIF_KNOSSOS_DEVICE)) {
                                        vm_vec_scale(&live_debris_obj->phys_info.vel, ship_obj->radius/250.0f);
                                }
                        }
                }
        }

        ship_model_stop(ship_obj);
}

void set_ship_submodel_as_blown_off(ship *shipp, char *name)
{
        int found =     FALSE;

        // go through list of ship subsystems and find name
        ship_subsys     *pss = NULL;
        for (pss=GET_FIRST(&shipp->subsys_list); pss!=END_OF_LIST(&shipp->subsys_list); pss=GET_NEXT(pss)) {
                if ( stricmp(pss->system_info->name, name) == 0) {
                        found = TRUE;
                        break;
                }
        }

        // set its blown off flag to TRUE
        Assert(found);
        if (found) {
                pss->submodel_info_1.blown_off = 1;
        }
}


// Create debris for ship submodel which has live debris (at ship death)
// when ship submodel has not already been blown off (and hence liberated live debris)
void shipfx_maybe_create_live_debris_at_ship_death( object *ship_obj )
{
        // if ship has live debris, detonate that subsystem now
        // search for any live debris

        ship *shipp = &Ships[ship_obj->instance];
        polymodel *pm = model_get(shipp->modelnum);

        int live_debris_submodel = -1;
        for (int idx=0; idx<pm->num_debris_objects; idx++) {
                if (pm->submodel[pm->debris_objects[idx]].is_live_debris) {
                        live_debris_submodel = pm->debris_objects[idx];

                        // get submodel that produces live debris
                        int model_get_parent_submodel_for_live_debris( int model_num, int live_debris_model_num );
                        int parent = model_get_parent_submodel_for_live_debris( shipp->modelnum, live_debris_submodel);
                        Assert(parent != -1);

                        // set model values only once (esp blown off)
                        ship_model_start(ship_obj);

                        // check if already blown off  (ship model set)
                        if ( !pm->submodel[parent].blown_off ) {
                
                                // get ship_subsys for live_debris
                                // Go through all subsystems and look for submodel the subsystems with "parent" submodel.
                                ship_subsys     *pss = NULL;
                                for ( pss = GET_FIRST(&shipp->subsys_list); pss != END_OF_LIST(&shipp->subsys_list); pss = GET_NEXT(pss) ) {
                                        if (pss->system_info->subobj_num == parent) {
                                                break;
                                        }
                                }

                                Assert (pss != NULL);
                                if (pss != NULL) {
                                        vector exp_center, tmp = {0.0f, 0.0f, 0.0f};
                                        model_find_world_point(&exp_center, &tmp, shipp->modelnum, parent, &ship_obj->orient, &ship_obj->pos );

                                        // if not blown off, blow it off
                                        shipfx_subsystem_mabye_create_live_debris(ship_obj, shipp, pss, &exp_center, 3.0f);

                                        // now set subsystem as blown off, so we only get one copy
                                        pm->submodel[parent].blown_off = 1;
                                        set_ship_submodel_as_blown_off(&Ships[ship_obj->instance], pss->system_info->name);
                                }
                        }
                }
        }

        // clean up
        ship_model_stop(ship_obj);

}

void shipfx_blow_off_subsystem(object *ship_obj,ship *ship_p,ship_subsys *subsys, vector *exp_center)
{
        vector subobj_pos;

        model_subsystem *psub = subsys->system_info;

        get_subsystem_world_pos(ship_obj, subsys, &subobj_pos);

/*
        if ( psub->turret_gun_sobj > -1 )
                debris_create( ship_obj, ship_p->modelnum, psub->turret_gun_sobj, &subobj_pos, exp_center, 0, 1.0f );

        if ( psub->subobj_num > -1 )
                debris_create( ship_obj, ship_p->modelnum, psub->subobj_num, &subobj_pos, exp_center, 0, 1.0f );
*/
        // get rid of sparks on submodel that is destroyed
        shipfx_remove_submodel_ship_sparks(ship_p, psub->subobj_num);

        // create debris shards
        shipfx_blow_up_model(ship_obj, ship_p->modelnum, psub->subobj_num, 50, &subobj_pos );

        // create live debris objects, if any
        // TODO:  some MULITPLAYER implcations here!!
        shipfx_subsystem_mabye_create_live_debris(ship_obj, ship_p, subsys, exp_center, 1.0f);

        // create first fireball
        fireball_create( &subobj_pos, FIREBALL_EXPLOSION_MEDIUM, OBJ_INDEX(ship_obj), psub->radius );
}


void shipfx_blow_up_hull(object *obj, int model, vector *exp_center)
{
        int i;
        polymodel * pm;
        ushort sig_save;


        pm = model_get(model);
        if (!pm) return;

        // in multiplayer, send a debris_hull_create packet.  Save/restore the debris signature
        // when in misison only (since we can create debris pieces before mission starts)
        sig_save = 0;
        if ( (Game_mode & GM_MULTIPLAYER) && (Game_mode & GM_IN_MISSION) ) {
                sig_save = multi_get_next_network_signature( MULTI_SIG_DEBRIS );
                multi_set_network_signature( (ushort)(Ships[obj->instance].arrival_distance), MULTI_SIG_DEBRIS );
        }

        bool try_live_debris = true;
        for (i=0; i<pm->num_debris_objects; i++ )       {
                if (! pm->submodel[pm->debris_objects[i]].is_live_debris) {
                        vector tmp = {0.0f, 0.0f, 0.0f };               
                        model_find_world_point(&tmp, &pm->submodel[pm->debris_objects[i]].offset, model, 0, &obj->orient, &obj->pos );
                        debris_create( obj, model, pm->debris_objects[i], &tmp, exp_center, 1, 3.0f );
                } else {
                        if ( try_live_debris ) {
                                // only create live debris once
                                // this creates *all* the live debris for *all* the currently live subsystems.
                                try_live_debris = false;
                                shipfx_maybe_create_live_debris_at_ship_death(obj);
                        }
                }
        }

        // restore the ship signature to it's original value.
        if ( (Game_mode & GM_MULTIPLAYER) && (Game_mode & GM_IN_MISSION) ) {
                multi_set_network_signature( sig_save, MULTI_SIG_DEBRIS );
        }
}


// Creates "ndebris" pieces of debris on random verts of the the "submodel" in the 
// ship's model.
void shipfx_blow_up_model(object *obj,int model, int submodel, int ndebris, vector *exp_center )
{
        int i;

        // if in a multiplayer game -- seed the random number generator with a value that will be the same
        // on all clients in the game -- the net_signature of the object works nicely -- since doing so should
        // ensure that all pieces of debris will get scattered in same direction on all machines
        if ( Game_mode & GM_MULTIPLAYER )
                srand( obj->net_signature );

        // made a change to allow anyone but multiplayer client to blow up hull.  Clients will do it when
        // they get the create packet
        if ( submodel == 0 ) {
                shipfx_blow_up_hull(obj,model, exp_center );
        }

        for (i=0; i<ndebris; i++ )      {
                vector pnt1, pnt2;

                // Gets two random points on the surface of a submodel
                submodel_get_two_random_points(model, submodel, &pnt1, &pnt2 );

                vector tmp, outpnt;

                vm_vec_avg( &tmp, &pnt1, &pnt2 );
                model_find_world_point(&outpnt, &tmp, model,submodel, &obj->orient, &obj->pos );

                debris_create( obj, -1, -1, &outpnt, exp_center, 0, 1.0f );
        }
}


// =================================================
//          SHIP WARP IN EFFECT CODE
// =================================================


// Given an ship, find the radius of it as viewed from the front.
static float shipfx_calculate_effect_radius( object *objp )
{
        float w,h,rad;
        ship *shipp = &Ships[objp->instance];

        polymodel *pm = model_get( shipp->modelnum );

        w = pm->maxs.x - pm->mins.x;
        h = pm->maxs.y - pm->mins.y;
        
        if ( w > h )    {
                rad = w / 2.0f;
        } else {
                rad = h / 2.0f;
        }

        object *docked_objp = ai_find_docked_object( objp );

        //      If ship is docked then center wormhold about their center and make radius large enough.
        if ( docked_objp ) {
                ship *docked_shipp = &Ships[docked_objp->instance];
                
                pm = model_get( docked_shipp->modelnum );
                
                w = pm->maxs.x - pm->mins.x;
                h = pm->maxs.y - pm->mins.y;
                
                if ( w > h )    {
                        rad += w / 2.0f;
                } else {
                        rad += h / 2.0f;
                }
        }
        return rad*3.0f;
}

// How long the stage 1 & stage 2 of warp in effect lasts.
// There are different times for small, medium, and large ships.
// The appropriate values are picked depending on the ship's
// radius.
#define SHIPFX_WARP_DELAY       (2.0f)          // time for warp effect to ramp up before ship moves into it.

// Give object objp, calculate how long it should take the
// ship to go through the warp effect and how fast the ship
// should go.   For reference,  capital ship of 2780m 
// should take 7 seconds to fly through.   Fighters of 30, 
// should take 1.5 seconds to fly through.

#define LARGEST_RAD 1390.0f 
#define LARGEST_RAD_TIME 7.0f

#define SMALLEST_RAD 15.0f
#define SMALLEST_RAD_TIME 1.5f


static float shipfx_calculate_warp_time( object * objp )
{
        // Find rad_percent from 0 to 1, 0 being smallest ship, 1 being largest
        float rad_percent = (objp->radius-SMALLEST_RAD) / (LARGEST_RAD-SMALLEST_RAD);
        if ( rad_percent < 0.0f ) {
                rad_percent = 0.0f;
        } else if ( rad_percent > 1.0f )        {
                rad_percent = 1.0f;
        }
        float rad_time = rad_percent*(LARGEST_RAD_TIME-SMALLEST_RAD_TIME) + SMALLEST_RAD_TIME;

        return rad_time;
}

// calculate warp speed
float shipfx_calculate_warp_speed(object *objp)
{
        float length;

        Assert(objp->type == OBJ_SHIP);
        if (objp->type != OBJ_SHIP) {
                length = 2.0f * objp->radius;
        } else {
                length = ship_get_length(&Ships[objp->instance]);
        }
        return length / shipfx_calculate_warp_time(objp);
}


// This is called to actually warp this object in
// after all the flashy fx are done, or if the flashy 
// fx don't work for some reason.
void shipfx_actually_warpin(    ship *shipp, object *objp )
{
        shipp->flags &= (~SF_ARRIVING_STAGE_1);
        shipp->flags &= (~SF_ARRIVING_STAGE_2);

        // let physics in on it too.
        objp->phys_info.flags &= (~PF_WARP_IN);
}

// JAS - code to start the ship doing the warp in effect
// This also starts the animating 3d effect playing.
// There are two modes, stage 1 and stage 2.   Stage 1 is
// when the ship just invisibly waits for a certain time
// period after the effect starts, and then stage 2 begins,
// where the ships flies through the effect at a set
// velocity so it gets through in a certain amount of
// time.
void shipfx_warpin_start( object *objp )
{
        ship *shipp;
        float effect_time, effect_radius;
        
        shipp = &Ships[objp->instance];

        if ( shipp->flags & SF_ARRIVING )       {
                mprintf(( "Ship is already arriving!\n" ));
                return;
        }

        // post a warpin event
        if(Game_mode & GM_DEMO_RECORD){
                demo_POST_warpin(objp->signature, shipp->flags);
        }

        // if there is no arrival warp, then skip the whole thing
        if ( shipp->flags & SF_NO_ARRIVAL_WARP )        {
                shipfx_actually_warpin(shipp,objp);
                return;
        }
        
        // VALIDATE special_warp_objnum
        if (shipp->special_warp_objnum >= 0) {
                        
                int ref_objnum = shipp->special_warp_objnum;
                int valid_reference_ship = FALSE;

                // Validate reference_objnum
                if ((ref_objnum >= 0) && (ref_objnum < MAX_OBJECTS)) {
                        object *sp_objp = &Objects[ref_objnum];
                        if (sp_objp->type == OBJ_SHIP) {
                                if (Ship_info[Ships[sp_objp->instance].ship_info_index].flags & SIF_KNOSSOS_DEVICE) {
                                        valid_reference_ship = TRUE;
                                }
                        }
                }

                if (valid_reference_ship != TRUE) {
                        shipp->special_warp_objnum = -1;
                }
        }

        // only move warp effect pos if not special warp in.
        if (shipp->special_warp_objnum >= 0) {
                Assert(!(Game_mode & GM_MULTIPLAYER));
                polymodel *pm;
                pm = model_get(shipp->modelnum);
                vm_vec_scale_add(&shipp->warp_effect_pos, &objp->pos, &objp->orient.fvec, -pm->mins.z);
        } else {
                vm_vec_scale_add( &shipp->warp_effect_pos, &objp->pos, &objp->orient.fvec, objp->radius );
        }
        
        // The ending zero mean this is a warp-in effect
        if ( !(shipp->flags & SF_INITIALLY_DOCKED) ) {
                int warp_objnum;

                // Effect time is 'SHIPFX_WARP_DELAY' (1.5 secs) seconds to start, 'shipfx_calculate_warp_time' 
                // for ship to go thru, and 'SHIPFX_WARP_DELAY' (1.5 secs) to go away.
                effect_time = shipfx_calculate_warp_time(objp) + SHIPFX_WARP_DELAY + SHIPFX_WARP_DELAY;
                effect_radius = shipfx_calculate_effect_radius(objp);

                // maybe special warpin
                if (shipp->special_warp_objnum >= 0) {
                        // cap radius to size of knossos
                        effect_radius = min(effect_radius, 0.8f*Objects[shipp->special_warp_objnum].radius);
                        warp_objnum = fireball_create(&shipp->warp_effect_pos, FIREBALL_KNOSSOS_EFFECT, shipp->special_warp_objnum, effect_radius, 0, NULL, effect_time, shipp->ship_info_index);
                } else {
                        warp_objnum = fireball_create(&shipp->warp_effect_pos, FIREBALL_WARP_EFFECT, OBJ_INDEX(objp), effect_radius, 0, NULL, effect_time, shipp->ship_info_index);
                }
                if (warp_objnum < 0 )   {       // JAS: This must always be created, if not, just warp the ship in
                        shipfx_actually_warpin(shipp,objp);
                        return;
                }

                shipp->warp_effect_fvec = Objects[warp_objnum].orient.fvec;
                // maybe negate if special warp effect
                if (shipp->special_warp_objnum >= 0) {
                        if (vm_vec_dotprod(&shipp->warp_effect_fvec, &objp->orient.fvec) < 0) {
                                vm_vec_negate(&shipp->warp_effect_fvec);
                        }
                }


                shipp->final_warp_time = timestamp(fl2i(SHIPFX_WARP_DELAY*1000.0f));
                shipp->flags |= SF_ARRIVING_STAGE_1;

                // see if this ship is docked with anything, and if so, make docked ship be "arriving"
                /*
                if ( Ai_info[shipp->ai_index].dock_objnum != -1 ) {
                        Ships[Ai_info[shipp->ai_index].dock_objnum].final_warp_time = timestamp(fl2i(warp_time*1000.0f));
                        Ships[Ai_info[shipp->ai_index].dock_objnum].flags |= SF_ARRIVING_STAGE_1;
                }
                */
        }
}

void shipfx_warpin_frame( object *objp, float frametime )
{
        ship *shipp;

        shipp = &Ships[objp->instance];

        if ( shipp->flags & SF_DYING ) return;

        if ( shipp->flags & SF_ARRIVING_STAGE_1 )       {
                if ( timestamp_elapsed(shipp->final_warp_time) ) {

                        // let physics know the ship is going to warp in.
                        objp->phys_info.flags |= PF_WARP_IN;

                        // done doing stage 1 of warp, so go on to stage 2
                        shipp->flags &= (~SF_ARRIVING_STAGE_1);
                        shipp->flags |= SF_ARRIVING_STAGE_2;

                        float warp_time = shipfx_calculate_warp_time(objp);
                        float speed = shipfx_calculate_warp_speed(objp);                        // How long it takes to move through warp effect

                        // Make ship move at velocity so that it moves two radius's in warp_time seconds.
                        vector vel;
                        vel = objp->orient.fvec;
                        vm_vec_scale( &vel, speed );
                        objp->phys_info.vel = vel;
                        objp->phys_info.desired_vel = vel;
                        objp->phys_info.prev_ramp_vel.x = 0.0f;
                        objp->phys_info.prev_ramp_vel.y = 0.0f;
                        objp->phys_info.prev_ramp_vel.z = speed;
                        objp->phys_info.forward_thrust = 0.0f;          // How much the forward thruster is applied.  0-1.

                        shipp->final_warp_time = timestamp(fl2i(warp_time*1000.0f));

                        /*
                        // see if this ship is docked with anything, and if so, make docked ship be "arriving"
                        if ( Ai_info[shipp->ai_index].dock_objnum != -1 ) {
                                Ships[Ai_info[shipp->ai_index].dock_objnum].flags &= (~SF_ARRIVING_STAGE_1);
                                Ships[Ai_info[shipp->ai_index].dock_objnum].flags |= SF_ARRIVING_STAGE_2;
                                Ships[Ai_info[shipp->ai_index].dock_objnum].final_warp_time = timestamp(fl2i(warp_time*1000.0f));
                        }
                        */
                } 
        } else if ( shipp->flags & SF_ARRIVING_STAGE_2 )        {
                if ( timestamp_elapsed(shipp->final_warp_time) ) {
                        // done doing stage 2 of warp, so turn off arriving flag
                        shipfx_actually_warpin(shipp,objp);

                        // notify physics to slow down
                        if (Ship_info[shipp->ship_info_index].flags & SIF_SUPERCAP) {
                                // let physics know this is a special warp in
                                objp->phys_info.flags |= PF_SPECIAL_WARP_IN;
                        }
                }
        }

}
 
// This is called to actually warp this object out
// after all the flashy fx are done, or if the flashy 
// fx don't work for some reason.  OR to skip the flashy
// fx.
void shipfx_actually_warpout( ship *shipp, object *objp )
{
        // Once we get through effect, make the ship go away

        if ( objp == Player_obj )       {
                // Normally, this will never get called for the player. If it
                // does, it is because some error (like the warpout effect
                // couldn't start) so go ahead an warp the player out.
                // All this does is set the event to go to debriefing, the
                // same thing that happens after the player warp out effect
                // ends.
                gameseq_post_event( GS_EVENT_DEBRIEF ); // proceed to debriefing
        } else {
                object *docked_objp;
                
                // Code for objects except player ship warping out
                objp->flags |= OF_SHOULD_BE_DEAD;
                // check to see if departing ship is docked with anything and if so, mark that object
                // gone as well
                docked_objp = ai_find_docked_object( objp );
                if ( docked_objp ) {
                        docked_objp->flags |= OF_SHOULD_BE_DEAD;
                }

                ship_departed( objp->instance );
                if ( docked_objp ){
                        ship_departed( docked_objp->instance );
                }
        }
}

// compute_special_warpout_stuff();
int compute_special_warpout_stuff(object *objp, float *speed, float *warp_time, vector *warp_pos)
{
        object  *sp_objp = NULL;
        ship            *shipp;
        int             valid_refenence_ship = FALSE, ref_objnum;
        vector  facing_normal, vec_to_knossos;
        float           dist_to_plane;

        // knossos warpout only valid in single player
        if (Game_mode & GM_MULTIPLAYER) {
                mprintf(("special warpout only for single player\n"));
                return -1;
        }

        // find special warp ship reference
        valid_refenence_ship = FALSE;
        ref_objnum = Ships[objp->instance].special_warp_objnum;

        // Validate reference_objnum
        if ((ref_objnum >= 0) && (ref_objnum < MAX_OBJECTS)) {
                sp_objp = &Objects[ref_objnum];
                if (sp_objp->type == OBJ_SHIP) {
                        shipp = &Ships[sp_objp->instance];
                        if (Ship_info[shipp->ship_info_index].flags & SIF_KNOSSOS_DEVICE) {
                                valid_refenence_ship = TRUE;
                        }
                }
        }
        
        if (!valid_refenence_ship) {
                Int3();
                mprintf(("special warpout reference ship not found\n"));
                return -1;
        }

        // get facing normal from knossos
        vm_vec_sub(&vec_to_knossos, &sp_objp->pos, &objp->pos);
        facing_normal = sp_objp->orient.fvec;
        if (vm_vec_dotprod(&vec_to_knossos, &sp_objp->orient.fvec) > 0) {
                vm_vec_negate(&facing_normal);
        }

        // find position to play the warp ani..
        dist_to_plane = fvi_ray_plane(warp_pos, &sp_objp->pos, &facing_normal, &objp->pos, &objp->orient.fvec, 0.0f);

        // calculate distance to warpout point.
        polymodel *pm = model_get(Ships[objp->instance].modelnum);
        dist_to_plane += pm->mins.z;

        if (dist_to_plane < 0) {
                mprintf(("warpout started too late\n"));
                return -1;
        }

        // validate angle
        float max_warpout_angle = 0.707f;       // 45 degree half-angle cone for small ships
        if (Ship_info[Ships[objp->instance].ship_info_index].flags & (SIF_BIG_SHIP | SIF_HUGE_SHIP)) {
                max_warpout_angle = 0.866f;     // 30 degree half-angle cone for BIG or HUGE
        }

        if (-vm_vec_dotprod(&objp->orient.fvec, &facing_normal) < max_warpout_angle) {  // within allowed angle
                Int3();
                mprintf(("special warpout angle exceeded\n"));
                return -1;
        }

        // Calculate speed needed to get 
        *speed = shipfx_calculate_warp_speed(objp);
        
        // Calculate how long to fly through the effect.  Not to get to the effect, just through it.
        *warp_time = shipfx_calculate_warp_time(objp);
        *warp_time += dist_to_plane / *speed;

        return 0;
}


void compute_warpout_stuff(object *objp, float *speed, float *warp_time, vector *warp_pos)
{
        // If we're warping through the knossos, do something different.
        if (Ships[objp->instance].special_warp_objnum >= 0) {
                if (compute_special_warpout_stuff(objp, speed, warp_time, warp_pos) != -1) {
                        return;
                } else {
                        mprintf(("Invalid special warp\n"));
                }
        }

        object  *docked_objp = ai_find_docked_object( objp );
        vector  center_pos = objp->pos;
        float           radius, ship_move_dist, warp_dist;

        radius = objp->radius;

        //      If ship is docked then center wormhold about their center and make radius large enough.
        if ( docked_objp ) {
                vm_vec_avg(&center_pos, &objp->pos, &docked_objp->pos);
                radius += docked_objp->radius;
        }

        // Calculate how long to fly through the effect.  Not to get to the effect, just through it.
        *warp_time = shipfx_calculate_warp_time(objp);

        // Pick some speed at which we want to go through the warp effect.  
        // This is determined by shipfx_calculate_warp_time specifying how long
        // it should take to go through the effect, or 2R.
        *speed = shipfx_calculate_warp_speed(objp);

        if ( objp == Player_obj )       {
                *speed = 0.8f*objp->phys_info.max_vel.z;
        }

        // Now we know our speed. Figure out how far the warp effect will be from here.  
        ship_move_dist = (*speed * SHIPFX_WARP_DELAY) + radius*1.5f;            // We want to get to 1.5R away from effect
        if ( ship_move_dist < radius*1.5f ) {
                ship_move_dist = radius*1.5f;
        }

        // If this is a huge ship, set the distance to the length of the ship
        if (Ship_info[Ships[objp->instance].ship_info_index].flags & SIF_HUGE_SHIP) {
                ship_move_dist = 0.5f * ship_get_length(&Ships[objp->instance]);
        }

        // Acount for time to get to warp effect, before we actually go through it.
        *warp_time += ship_move_dist / *speed;

        warp_dist = ship_move_dist;
        // allow for off center
        if (Ship_info[Ships[objp->instance].ship_info_index].flags & SIF_HUGE_SHIP) {
                polymodel *pm = model_get(Ships[objp->instance].modelnum);
                warp_dist -= pm->mins.z;
        }

        vm_vec_scale_add( warp_pos, &center_pos, &objp->orient.fvec, warp_dist );
}

// JAS - code to start the ship doing the warp out effect
// This puts the ship into a mode specified by SF_DEPARTING
// where it flies forward for a set time period at a set
// velocity, then disappears when that time is reached.  This
// also starts the animating 3d effect playing.
void shipfx_warpout_start( object *objp )
{
        float warp_time;
        ship *shipp;
        shipp = &Ships[objp->instance];

        if (    shipp->flags & SF_DEPART_WARP ) {
                mprintf(( "Ship is already departing!\n" ));
                return;
        }

        // if we're dying return
        if ( shipp->flags & SF_DYING ) {
                return;
        }

        // if we're HUGE, keep alive - set guardian
        if (Ship_info[shipp->ship_info_index].flags & SIF_HUGE_SHIP) {
                objp->flags |= OF_GUARDIAN;
        }

        // post a warpin event
        if(Game_mode & GM_DEMO_RECORD){
                demo_POST_warpout(objp->signature, shipp->flags);
        }

        // don't send ship depart packets for player ships
        if ( (MULTIPLAYER_MASTER) && !(objp->flags & OF_PLAYER_SHIP) ){
                send_ship_depart_packet( objp );
        }

        // don't do departure wormhole if ship flag is set which indicates no effect
        if ( shipp->flags & SF_NO_DEPARTURE_WARP ) {
                // DKA 5/25/99 If he's going to warpout, set it.  
                // Next line fixes assert in wing cleanup code when no warp effect.
                shipp->flags |= SF_DEPART_WARP;

                shipfx_actually_warpout(shipp, objp);
                return;
        }

        if ( objp == Player_obj )       {
                HUD_printf(XSTR( "Subspace node activated", 498) );
        }

        float   speed, effect_time, effect_radius;
        vector  warp_pos;
        // warp time from compute warpout stuff includes time to get up to warp_pos
        compute_warpout_stuff(objp, &speed, &warp_time, &warp_pos);
        shipp->warp_effect_pos = warp_pos;

        // The ending one means this is a warp-out effect
        int warp_objnum;
        // Effect time is 'SHIPFX_WARP_DELAY' (1.5 secs) seconds to start, 'shipfx_calculate_warp_time' 
        // for ship to go thru, and 'SHIPFX_WARP_DELAY' (1.5 secs) to go away.
        // effect_time = shipfx_calculate_warp_time(objp) + SHIPFX_WARP_DELAY + SHIPFX_WARP_DELAY;
        effect_time = warp_time + SHIPFX_WARP_DELAY;
        effect_radius = shipfx_calculate_effect_radius(objp);

        // maybe special warpout
        if (shipp->special_warp_objnum >= 0) {
                // cap radius to size of knossos
                effect_radius = min(effect_radius, 0.8f*Objects[shipp->special_warp_objnum].radius);
                warp_objnum = fireball_create(&shipp->warp_effect_pos, FIREBALL_KNOSSOS_EFFECT, shipp->special_warp_objnum, effect_radius, 1, NULL, effect_time, shipp->ship_info_index);
        } else {
                warp_objnum = fireball_create(&shipp->warp_effect_pos, FIREBALL_WARP_EFFECT, OBJ_INDEX(objp), effect_radius, 1, NULL, effect_time, shipp->ship_info_index);
        }
        if (warp_objnum < 0 )   {       // JAS: This must always be created, if not, just warp the ship in
                shipfx_actually_warpout(shipp,objp);
                return;
        }

        shipp->warp_effect_fvec = Objects[warp_objnum].orient.fvec;
        // maybe negate if special warp effect
        if (shipp->special_warp_objnum >= 0) {
                if (vm_vec_dotprod(&shipp->warp_effect_fvec, &objp->orient.fvec) > 0) {
                        vm_vec_negate(&shipp->warp_effect_fvec);
                }
        }

        // Make the warp effect stage 1 last SHIP_WARP_TIME1 seconds.
        if ( objp == Player_obj )       {
                warp_time = fireball_lifeleft(&Objects[warp_objnum]);
                shipp->final_warp_time = timestamp(fl2i(warp_time*1000.0f));
        } else {
                shipp->final_warp_time = timestamp(fl2i(warp_time*2.0f*1000.0f));
        }
        shipp->flags |= SF_DEPART_WARP;

//      mprintf(( "Warp time = %.4f , effect time = %.4f ms\n", warp_time*1000.0f, effect_time ));

        // This is a hack to make the ship go at the right speed to go from it's current position to the warp_effect_pos;
        
        // Set ship's velocity to 'speed'
        // This should actually be an AI that flies from the current
        // position through 'shipp->warp_effect_pos' in 'warp_time'
        // and keeps going 
        if ( objp != Player_obj )       {
                vector vel;
                vel = objp->orient.fvec;
                vm_vec_scale( &vel, speed );
                objp->phys_info.vel = vel;
                objp->phys_info.desired_vel = vel;
                objp->phys_info.prev_ramp_vel.x = 0.0f;
                objp->phys_info.prev_ramp_vel.y = 0.0f;
                objp->phys_info.prev_ramp_vel.z = speed;
                objp->phys_info.forward_thrust = 1.0f;          // How much the forward thruster is applied.  0-1.

                // special case for HUGE ships
                if (Ship_info[shipp->ship_info_index].flags & SIF_HUGE_SHIP) {
//                      objp->phys_info.flags |= PF_SPECIAL_WARP_OUT;
                }
        }

}

void shipfx_warpout_frame( object *objp, float frametime )
{
        ship *shipp;
        shipp = &Ships[objp->instance];

        if ( shipp->flags & SF_DYING ) return;

        vector tempv;
        float warp_pos; // position of warp effect in object's frame of reference

        vm_vec_sub( &tempv, &objp->pos, &shipp->warp_effect_pos );
        warp_pos = -vm_vec_dot( &tempv, &shipp->warp_effect_fvec );


        // Find the closest point on line from center of wormhole
        vector pos;
        float dist;

        fvi_ray_plane(&pos,&objp->pos,&shipp->warp_effect_fvec,&shipp->warp_effect_pos, &shipp->warp_effect_fvec, 0.0f );
        dist = vm_vec_dist( &pos, &objp->pos );

//      mprintf(( "Warp pos = %.1f, rad=%.1f, center dist = %.1f\n", warp_pos, objp->radius, dist ));

        if ( objp == Player_obj )       {
                // Code for player warpout frame

                if ( (Player->control_mode==PCM_WARPOUT_STAGE2) && (warp_pos > objp->radius) )  {
                        gameseq_post_event( GS_EVENT_PLAYER_WARPOUT_DONE_STAGE2 );
                }

                if ( timestamp_elapsed(shipp->final_warp_time) ) {

                        // Something went wrong... oh well, warp him out anyway.
                        if ( Player->control_mode != PCM_WARPOUT_STAGE3 )       {
                                mprintf(( "Hmmm... player ship warpout time elapsed, but he wasn't in warp stage 3.\n" ));
                        }

                        gameseq_post_event( GS_EVENT_PLAYER_WARPOUT_DONE );
                        ship_departed( objp->instance );                                                                // mark log entry for the player
                }

        } else {
                // Code for all non-player ships warpout frame

                int timed_out = timestamp_elapsed(shipp->final_warp_time);
                if ( timed_out )        {
//                      mprintf(("Frame %i: Ship %s missed departue cue.\n", Framecount, shipp->ship_name ));
                        int     delta_ms = timestamp_until(shipp->final_warp_time);
                        if (delta_ms > 1000.0f * frametime ) {
                                nprintf(("AI", "Frame %i: Ship %s missed departue cue by %7.3f seconds.\n", Framecount, shipp->ship_name, - (float) delta_ms/1000.0f));
                        }
                }

                // MWA 10/21/97 -- added shipp->flags & SF_NO_DEPARTURE_WARP part of next if statement.  For ships
                // that don't get a wormhole effect, I wanted to drop into this code immediately.
                if ( (warp_pos > objp->radius)  || (shipp->flags & SF_NO_DEPARTURE_WARP) || timed_out ) {
                        shipfx_actually_warpout( shipp, objp );
                } 
        }
}


//==================================================
// Stuff for keeping track of which ships are in
// whose shadows.


// Given point p0, in object's frame of reference, find if 
// it can see the sun.
int shipfx_point_in_shadow( vector *p0, matrix *src_orient, vector *src_pos, float radius )
{
        mc_info mc;
        object *objp;
        ship_obj *so;
        ship *shipp;
        int n_lights;
        int idx;

        vector rp0, rp1;

        vector light_dir;

        // Move rp0 into world coordinates      
        vm_vec_unrotate(&rp0, p0, src_orient);
        vm_vec_add2(&rp0, src_pos);

        // get the # of global lights
        n_lights = light_get_global_count();
        
        for(idx=0; idx<n_lights; idx++){
                // get the light dir for this light
                light_get_global_dir(&light_dir, idx);

                // Find rp1
                vm_vec_scale_add( &rp1, &rp0, &light_dir, 10000.0f );

                for ( so = GET_FIRST(&Ship_obj_list); so != END_OF_LIST(&Ship_obj_list); so = GET_NEXT(so) )    {
                        objp = &Objects[so->objnum];
                        shipp = &Ships[objp->instance];

                        mc.model_num = shipp->modelnum;
                        mc.orient = &objp->orient;
                        mc.pos = &objp->pos;
                        mc.p0 = &rp0;
                        mc.p1 = &rp1;
                        mc.flags = MC_CHECK_MODEL;      

                        if ( model_collide(&mc) ){
                                return 1;
                        }
                }
        }

        // not in shadow
        return 0;
}


// Given an ship see if it is in a shadow.
int shipfx_in_shadow( object * src_obj )
{
        mc_info mc;
        object *objp;
        ship_obj *so;
        ship *shipp;
        int n_lights;
        int idx;

        vector rp0, rp1;
        vector light_dir;

        rp0 = src_obj->pos;
        
        // get the # of global lights
        n_lights = light_get_global_count();

        for(idx=0; idx<n_lights; idx++){
                // get the direction for this light
                light_get_global_dir(&light_dir, idx);

                // Find rp1
                for ( so = GET_FIRST(&Ship_obj_list); so != END_OF_LIST(&Ship_obj_list); so = GET_NEXT(so) )    {
                        objp = &Objects[so->objnum];

                        if ( src_obj != objp )  {
                                shipp = &Ships[objp->instance];

                                vm_vec_scale_add( &rp1, &rp0, &light_dir, objp->radius*10.0f );

                                mc.model_num = shipp->modelnum;
                                mc.orient = &objp->orient;
                                mc.pos = &objp->pos;
                                mc.p0 = &rp0;
                                mc.p1 = &rp1;
                                mc.flags = MC_CHECK_MODEL;      

        //                      mc.flags |= MC_CHECK_SPHERELINE;
        //                      mc.radius = src_obj->radius;

                                if ( model_collide(&mc) )       {
                                        return 1;
                                }
                        }
                }
        }

        // not in shadow
        return 0;
}

// Given world point see if it is in a shadow.
int shipfx_eye_in_shadow( vector *eye_pos, object * src_obj, int sun_n )
{
        mc_info mc;
        object *objp;
        ship_obj *so;
        ship *shipp;    

        vector rp0, rp1;
        vector light_dir;

        rp0 = *eye_pos; 
        
        // get the light dir
        if(!light_get_global_dir(&light_dir, sun_n)){
                return 0;
        }

        // Find rp1
        for ( so = GET_FIRST(&Ship_obj_list); so != END_OF_LIST(&Ship_obj_list); so = GET_NEXT(so) )    {
                objp = &Objects[so->objnum];

                if ( src_obj != objp )  {
                        shipp = &Ships[objp->instance];

                        vm_vec_scale_add( &rp1, &rp0, &light_dir, objp->radius*10.0f );

                        ship_model_start(objp);

                        mc.model_num = shipp->modelnum;
                        mc.orient = &objp->orient;
                        mc.pos = &objp->pos;
                        mc.p0 = &rp0;
                        mc.p1 = &rp1;
                        mc.flags = MC_CHECK_MODEL;      

        //                      mc.flags |= MC_CHECK_SPHERELINE;
        //                      mc.radius = src_obj->radius;

                        int hit = model_collide(&mc);

                        ship_model_stop(objp);

                        if (hit) {
                                return 1;
                        }
                }
        }

        // Check all the big hull debris pieces.
        debris  *db = Debris;

        int i;
        for ( i = 0; i < MAX_DEBRIS_PIECES; i++, db++ ) {
                if ( !(db->flags & DEBRIS_USED) || !db->is_hull ){
                        continue;
                }

                objp = &Objects[db->objnum];

                vm_vec_scale_add( &rp1, &rp0, &light_dir, objp->radius*10.0f );

                mc.model_num = db->model_num;   // Fill in the model to check
                mc.submodel_num = db->submodel_num;
                model_clear_instance( mc.model_num );
                mc.orient = &objp->orient;                                      // The object's orient
                mc.pos = &objp->pos;                                                    // The object's position
                mc.p0 = &rp0;                           // Point 1 of ray to check
                mc.p1 = &rp1;                                   // Point 2 of ray to check
                mc.flags = (MC_CHECK_MODEL | MC_SUBMODEL);

                if (model_collide(&mc)) {
                        return 1;
                }
        }       

        // not in shadow
        return 0;
}

//=====================================================================================
// STUFF FOR DOING SHIP GUN FLASHES
//=====================================================================================

#define MAX_FLASHES     128                     // How many flashes total
#define FLASH_LIFE_PRIMARY              0.25f                   // How long flash lives
#define FLASH_LIFE_SECONDARY    0.50f                   // How long flash lives


typedef struct ship_flash {
        int     objnum;                                 // object number of parent ship
        int     obj_signature;                  // signature of that object
        int     light_num;                              // which light in the model this uses
        float   life;                                           // how long this should be around
        float max_life;                         // how long this has been around.
} ship_flash;

int Ship_flash_inited = 0;
int Ship_flash_highest = -1;
ship_flash Ship_flash[MAX_FLASHES];

// Resets the ship flash stuff. Call before each level.
void shipfx_flash_init()
{
        int i;
        
        for (i=0; i<MAX_FLASHES; i++ )  {
                Ship_flash[i].objnum = -1;                      // mark as unused
        }
        Ship_flash_highest = -1;
        Ship_flash_inited = 1;  
}


// Given that a ship fired a weapon, light up the model
// accordingly.
void shipfx_flash_create(object *objp, ship * shipp, vector *gun_pos, vector *gun_dir, int is_primary, int weapon_info_index)
{
        int i;
        int objnum = OBJ_INDEX(objp);

        Assert(Ship_flash_inited);

        polymodel *pm = model_get( shipp->modelnum );
        int closest_light = -1;
        float d, closest_dist = 0.0f;

        // ALWAYS do this - since this is called once per firing
        // if this is a cannon type weapon, create a muzzle flash
        // HACK - let the flak guns do this on their own since they fire so quickly
        if((Weapon_info[weapon_info_index].wi_flags & WIF_MFLASH) && !(Weapon_info[weapon_info_index].wi_flags & WIF_FLAK)){
                // spiffy new flash stuff
                mflash_create(gun_pos, gun_dir, Weapon_info[weapon_info_index].muzzle_flash);           
        }

        if ( pm->num_lights < 1 ) return;

        for (i=0; i<pm->num_lights; i++ )       {
                d = vm_vec_dist( &pm->lights[i].pos, gun_pos );
        
                if ( pm->lights[i].type == BSP_LIGHT_TYPE_WEAPON ) {
                        if ( (closest_light==-1) || (d<closest_dist) )  {
                                closest_light = i;
                                closest_dist = d;
                        }
                }
        }

        if ( closest_light == -1 ) return;

        int first_slot = -1;

        for (i=0; i<=Ship_flash_highest; i++ )  {
                if ( (first_slot==-1) && (Ship_flash[i].objnum < 0) )   {
                        first_slot = i;
                }

                if ( (Ship_flash[i].objnum == objnum) && (Ship_flash[i].obj_signature==objp->signature) )       {
                        if ( Ship_flash[i].light_num == closest_light ) {
                                // This is already flashing!
                                Ship_flash[i].life = 0.0f;
                                if ( is_primary )       {
                                        Ship_flash[i].max_life = FLASH_LIFE_PRIMARY;
                                } else {
                                        Ship_flash[i].max_life = FLASH_LIFE_SECONDARY;
                                }
                                return;
                        }
                }
        }

        if ( first_slot == -1 ) {
                if ( Ship_flash_highest < MAX_FLASHES-1 )       {
                        Ship_flash_highest++;
                        first_slot = Ship_flash_highest;
                } else {
                        //mprintf(( "SHIP_FLASH: Out of flash spots!\n" ));
                        return;         // out of flash slots
                }
        }

        Assert( Ship_flash[first_slot].objnum == -1 );

        Ship_flash[first_slot].objnum = objnum;
        Ship_flash[first_slot].obj_signature = objp->signature;
        Ship_flash[first_slot].life = 0.0f;             // Start it up
        if ( is_primary )       {
                Ship_flash[first_slot].max_life = FLASH_LIFE_PRIMARY;
        } else {
                Ship_flash[first_slot].max_life = FLASH_LIFE_SECONDARY;
        }
        Ship_flash[first_slot].light_num = closest_light;               
}

// Sets the flash lights in the model used by this
// ship to the appropriate values.  There might not
// be any flashes linked to this ship in which
// case this function does nothing.
void shipfx_flash_light_model( object *objp, ship * shipp )
{
        int i, objnum = OBJ_INDEX(objp);
        polymodel *pm = model_get( shipp->modelnum );

        for (i=0; i<=Ship_flash_highest; i++ )  {
                if ( (Ship_flash[i].objnum == objnum) && (Ship_flash[i].obj_signature==objp->signature) )       {
                        float v = (Ship_flash[i].max_life - Ship_flash[i].life)/Ship_flash[i].max_life;

                        pm->lights[Ship_flash[i].light_num].value += v / 255.0f;
                }
        }

}

// Does whatever processing needs to be done each frame.
void shipfx_flash_do_frame(float frametime)
{
        ship_flash *sf;
        int kill_it = 0;
        int i;

        for (i=0, sf = &Ship_flash[0]; i<=Ship_flash_highest; i++, sf++ )       {
                if ( sf->objnum > -1 )  {
                        if ( Objects[sf->objnum].signature != sf->obj_signature )       {
                                kill_it = 1;
                        }
                        sf->life += frametime;
                        if ( sf->life >= sf->max_life ) kill_it = 1;

                        if (kill_it) {
                                sf->objnum = -1;
                                if ( i == Ship_flash_highest )  {
                                        while( (Ship_flash_highest>0) && (Ship_flash[Ship_flash_highest].objnum == -1) )        {
                                                Ship_flash_highest--;
                                        }
                                }
                        }       
                }
        }       

}

float Particle_width = 1.2f;
DCF(particle_width, "Multiplier for angular width of the particle spew")
{
        if ( Dc_command ) {
                dc_get_arg(ARG_FLOAT);
                if ( (Dc_arg_float >= 0 ) && (Dc_arg_float <= 5) ) {
                        Particle_width = Dc_arg_float;
                } else {
                        dc_printf( "Illegal value for particle width. (Must be from 0-5) \n\n");
                }
        }
}

float Particle_number = 1.2f;
DCF(particle_num, "Multiplier for the number of particles created")
{
        if ( Dc_command ) {
                dc_get_arg(ARG_FLOAT);
                if ( (Dc_arg_float >= 0 ) && (Dc_arg_float <= 5) ) {
                        Particle_number = Dc_arg_float;
                } else {
                        dc_printf( "Illegal value for particle num. (Must be from 0-5) \n\n");
                }
        }
}

float Particle_life = 1.2f;
DCF(particle_life, "Multiplier for the lifetime of particles created")
{
        if ( Dc_command ) {
                dc_get_arg(ARG_FLOAT);
                if ( (Dc_arg_float >= 0 ) && (Dc_arg_float <= 5) ) {
                        Particle_life = Dc_arg_float;
                } else {
                        dc_printf( "Illegal value for particle life. (Must be from 0-5) \n\n");
                }
        }
}

// Make sparks fly off of ship n.
// sn = spark number to spark, corrosponding to element in
//      ship->hitpos array.  If this isn't -1, it is a just
//      got hit by weapon spark, otherwise pick one randomally.
void shipfx_emit_spark( int n, int sn )
{
        int create_spark = 1;
        object * obj;
        vector outpnt;
        ship *shipp = &Ships[n];
        float ship_radius, spark_scale_factor;
        
        if ( shipp->num_hits <= 0 )
                return;

        // get radius of ship
        ship_radius = model_get_radius(Ship_info[shipp->ship_info_index].modelnum);

        // get spark_scale_factor -- how much to increase ship sparks, based on radius
        if (ship_radius > 40) {
                spark_scale_factor = 1.0f;
        } else if (ship_radius > 20) {
                spark_scale_factor = (ship_radius - 20.0f) / 20.0f;
        } else {
                spark_scale_factor = 0.0f;
        }

        float spark_time_scale  = 1.0f + spark_scale_factor * (Particle_life   - 1.0f);
        float spark_width_scale = 1.0f + spark_scale_factor * (Particle_width  - 1.0f);
        float spark_num_scale   = 1.0f + spark_scale_factor * (Particle_number - 1.0f);

        obj = &Objects[shipp->objnum];
        ship_info* si = &Ship_info[shipp->ship_info_index];

        float hull_percent = obj->hull_strength / si->initial_hull_strength;
        if (hull_percent < 0.001) {
                hull_percent = 0.001f;
        }
        float fraction = 0.1f * obj->radius / hull_percent;
        if (fraction > 1.0f) {
                fraction = 1.0f;
        }

        int spark_num;
        if ( sn == -1 ) {
                spark_num = myrand() % shipp->num_hits;
        } else {
                spark_num = sn;
        }

        // don't display sparks that have expired
        if ( timestamp_elapsed(shipp->sparks[spark_num].end_time) ) {
                return;
        }

        // get spark position
        if (shipp->sparks[spark_num].submodel_num != -1) {
                ship_model_start(obj);
                model_find_world_point(&outpnt, &shipp->sparks[spark_num].pos, shipp->modelnum, shipp->sparks[spark_num].submodel_num, &obj->orient, &obj->pos);
                ship_model_stop(obj);
        } else {
                // rotate sparks correctly with current ship orient
                vm_vec_unrotate(&outpnt, &shipp->sparks[spark_num].pos, &obj->orient);
                vm_vec_add2(&outpnt,&obj->pos);
        }

        if ( shipp->flags & (SF_ARRIVING|SF_DEPART_WARP) ) {
                vector tmp;
                vm_vec_sub( &tmp, &outpnt, &shipp->warp_effect_pos );
                if ( vm_vec_dot( &tmp, &shipp->warp_effect_fvec ) < 0.0f )      {
                        // if in front of warp plane, don't create.
                        create_spark = 0;
                }
        }

        if ( create_spark )     {

                particle_emitter        pe;

                pe.pos = outpnt;                                // Where the particles emit from

                if ( shipp->flags & (SF_ARRIVING|SF_DEPART_WARP) ) {
                        // No velocity if going through warp.
                        pe.vel = vmd_zero_vector;
                } else {
                        // Initial velocity of all the particles.
                        // 0.0f = 0% of parent's.
                        // 1.0f = 100% of parent's.
                        vm_vec_copy_scale( &pe.vel, &obj->phys_info.vel, 0.7f );
                }

                // TODO: add velocity from rotation if submodel is rotating
                // v_rot = w x r

                // r = outpnt - model_find_world_point(0)

                // w = model_find_world_dir(
                // model_find_world_dir(&out_dir, &in_dir, model_num, submodel_num, &objorient, &objpos);

                vector tmp_norm, tmp_vel;
                vm_vec_sub( &tmp_norm, &outpnt, &obj->pos );
                vm_vec_normalize_safe(&tmp_norm);

                tmp_vel = obj->phys_info.vel;
                if ( vm_vec_normalize_safe(&tmp_vel) > 1.0f )   {
                        vm_vec_scale_add2(&tmp_norm,&tmp_vel, -2.0f);
                        vm_vec_normalize_safe(&tmp_norm);
                }
                                
                pe.normal = tmp_norm;                   // What normal the particle emit around
                pe.normal_variance = 0.3f;              //      How close they stick to that normal 0=good, 1=360 degree
                pe.min_rad = 0.20f;                             // Min radius
                pe.max_rad = 0.50f;                             // Max radius

                // first time through - set up end time and make heavier initially
                if ( sn > -1 )  {
                        // Sparks for first time at this spot
                        if (si->flags & SIF_FIGHTER) {
                                if (hull_percent > 0.6f) {
                                        // sparks only once when hull > 60%
                                        float spark_duration = (float)pow(2.0f, -5.0f*(hull_percent-1.3f)) * (1.0f + 0.6f*(frand()-0.5f));      // +- 30%
                                        shipp->sparks[spark_num].end_time = timestamp( (int) (1000.0f * spark_duration) );
                                } else {
                                        // spark never ends when hull < 60% (~277 hr)
                                        shipp->sparks[spark_num].end_time = timestamp( 100000000 );
                                }
                        }

                        if ( D3D_enabled ) {
                                pe.num_low  = 25;                               // Lowest number of particles to create (hardware)
                                pe.num_high = 30;                               // Highest number of particles to create (hardware)
                        } else {
                                pe.num_low  = 5;                                // Lowest number of particles to create (software)
                                pe.num_high = 7;                                // Highest number of particles to create (software)
                        }
                        pe.normal_variance = 1.0f;      //      How close they stick to that normal 0=good, 1=360 degree
                        pe.min_vel = 2.0f;                              // How fast the slowest particle can move
                        pe.max_vel = 12.0f;                             // How fast the fastest particle can move
                        pe.min_life = 0.05f;                            // How long the particles live
                        pe.max_life = 0.55f;                            // How long the particles live

                        particle_emit( &pe, PARTICLE_FIRE, 0 );
                } else {

                        pe.min_rad = 0.7f;                              // Min radius
                        pe.max_rad = 1.3f;                              // Max radius
                        if ( D3D_enabled ) {
                                pe.num_low  = int (20 * spark_num_scale);               // Lowest number of particles to create (hardware)
                                pe.num_high = int (50 * spark_num_scale);               // Highest number of particles to create (hardware)
                        } else {
                                pe.num_low  = 2;                        // Lowest number of particles to create (software)
                                pe.num_high = 8;                // Highest number of particles to create (software)
                        }
                        pe.normal_variance = 0.2f * spark_width_scale;          //      How close they stick to that normal 0=good, 1=360 degree
                        pe.min_vel = 3.0f;                              // How fast the slowest particle can move
                        pe.max_vel = 12.0f;                             // How fast the fastest particle can move
                        pe.min_life = 0.35f*2.0f * spark_time_scale;            // How long the particles live
                        pe.max_life = 0.75f*2.0f * spark_time_scale;            // How long the particles live
                        
                        particle_emit( &pe, PARTICLE_SMOKE, 0 );
                }
        }

        // Select time to do next spark
//      Ships[n].next_hit_spark = timestamp_rand(100,500);
        shipp->next_hit_spark = timestamp_rand(50,100);
}



//=====================================================================================
// STUFF FOR DOING LARGE SHIP EXPLOSIONS
//=====================================================================================

int     Bs_exp_fire_low = 1;
float   Bs_exp_fire_time_mult = 1.0f;

DCF_BOOL(bs_exp_fire_low, Bs_exp_fire_low)
DCF(bs_exp_fire_time_mult, "Multiplier time between fireball in big ship explosion")
{
        if ( Dc_command ) {
                dc_get_arg(ARG_FLOAT);
                if ( (Dc_arg_float >= 0.1 ) && (Dc_arg_float <= 5) ) {
                        Bs_exp_fire_time_mult = Dc_arg_float;
                } else {
                        dc_printf( "Illegal value for bs_exp_fire_time_mult. (Must be from 0.1-5) \n\n");
                }
        }
}

#define MAX_SPLIT_SHIPS         3               // How many can explode at once.  Each one is about 1K.

#define DEBRIS_NONE                     0
#define DEBRIS_DRAW                     1
#define DEBRIS_FREE                     2

typedef struct clip_ship {
        object*                 parent_obj;
        float                   length_left;    // uncomsumed length
        matrix                  orient;
        physics_info    phys_info;
        vector                  local_pivot;                                                            // world center of mass position of half ship
        vector                  model_center_disp_to_orig_center;       // displacement from half ship center to original model center
        vector                  clip_plane_norm;                                                        // clip plane normal (local [0,0,1] or [0,0,-1])
        float                           cur_clip_plane_pt;                                              // displacement from half ship clip plane to original model center
        float                           explosion_vel;
        ubyte                           draw_debris[MAX_DEBRIS_OBJECTS];
        int                             next_fireball;
} clip_ship;

typedef struct split_ship {
        int                             used;                                   // 0 if not used, 1 if used
        clip_ship               front_ship;
        clip_ship               back_ship;
        int                             explosion_flash_timestamp;
        int                             explosion_flash_started;
        int                             sound_handle[NUM_SUB_EXPL_HANDLES];
} split_ship;


static split_ship Split_ships[MAX_SPLIT_SHIPS];
static int Split_ships_inited = 0;

static void split_ship_init_system()
{
        int i;
        for (i=0; i<MAX_SPLIT_SHIPS; i++ )      {
                Split_ships[i].used = 0;
        }
        Split_ships_inited = 1;
}

static void maybe_fireball_wipe(clip_ship* half_ship, int* sound_handle);
static void split_ship_init( ship* shipp, split_ship* split_ship )
{
        object* parent_ship_obj = &Objects[shipp->objnum];
        matrix* orient = &parent_ship_obj->orient;
        for (int ii=0; ii<NUM_SUB_EXPL_HANDLES; ii++) {
                split_ship->sound_handle[ii] = shipp->sub_expl_sound_handle[ii];
        }

        // play 3d sound for shockwave explosion
        snd_play_3d( &Snds[SND_SHOCKWAVE_EXPLODE], &parent_ship_obj->pos, &View_position, 0.0f, NULL, 0, 1.0f, SND_PRIORITY_SINGLE_INSTANCE, NULL, 3.0f );

        // initialize both ships
        split_ship->front_ship.parent_obj = parent_ship_obj;
        split_ship->back_ship.parent_obj  = parent_ship_obj;
        split_ship->explosion_flash_timestamp = timestamp((int)(0.00075f*parent_ship_obj->radius));
        split_ship->explosion_flash_started = 0;
        split_ship->front_ship.orient = *orient;
        split_ship->back_ship.orient  = *orient;
        split_ship->front_ship.next_fireball = timestamp_rand(0, 100);
        split_ship->back_ship.next_fireball  = timestamp_rand(0, 100);

        split_ship->front_ship.clip_plane_norm = vmd_z_vector;
        vm_vec_copy_scale(&split_ship->back_ship.clip_plane_norm, &vmd_z_vector, -1.0f);

        // find the point at which the ship splits (relative to its pivot)
        polymodel* pm = model_get(shipp->modelnum);
        float init_clip_plane_dist;
        if (pm->num_split_plane > 0) {
                int index = rand()%pm->num_split_plane;
                init_clip_plane_dist = pm->split_plane[index];
        } else {
                init_clip_plane_dist = 0.5f * (0.5f - frand())*pm->core_radius;
        }

        split_ship->back_ship.cur_clip_plane_pt =  init_clip_plane_dist;
        split_ship->front_ship.cur_clip_plane_pt = init_clip_plane_dist;

        float dist;
        dist = (split_ship->front_ship.cur_clip_plane_pt+pm->maxs.z)/2.0f;
        vm_vec_copy_scale(&split_ship->front_ship.local_pivot, &orient->fvec, dist);
        vm_vec_make(&split_ship->front_ship.model_center_disp_to_orig_center, 0.0f, 0.0f, -dist);
        dist = (split_ship->back_ship.cur_clip_plane_pt +pm->mins.z)/2.0f;
        vm_vec_copy_scale(&split_ship->back_ship.local_pivot, &orient->fvec, dist);
        vm_vec_make(&split_ship->back_ship.model_center_disp_to_orig_center, 0.0f, 0.0f, -dist);
        vm_vec_add2(&split_ship->front_ship.local_pivot, &parent_ship_obj->pos );
        vm_vec_add2(&split_ship->back_ship.local_pivot,  &parent_ship_obj->pos );
        
        // find which debris pieces are in the front and back split ships
        for (int i=0; i<pm->num_debris_objects; i++ )   {
                vector temp_pos = {0.0f, 0.0f, 0.0f};
                vector tmp = {0.0f, 0.0f, 0.0f };               
                vector tmp1 = pm->submodel[pm->debris_objects[i]].offset;
                // tmp is world position,  temp_pos is world_pivot,  tmp1 is offset from world_pivot (in ship local coord)
                model_find_world_point(&tmp, &tmp1, shipp->modelnum, -1, &vmd_identity_matrix, &temp_pos );
                if (tmp.z > init_clip_plane_dist) {
                        split_ship->front_ship.draw_debris[i] = DEBRIS_DRAW;
                        split_ship->back_ship.draw_debris[i]  = DEBRIS_NONE;
                } else {
                        split_ship->front_ship.draw_debris[i] = DEBRIS_NONE;
                        split_ship->back_ship.draw_debris[i]  = DEBRIS_DRAW;
                }
        }

        /*
        // set the remaining debris slots to not draw
        for (i=pm->num_debris_objects; i<MAX_DEBRIS_OBJECTS; i++) {
                split_ship->front_ship.draw_debris[i] = DEBRIS_NONE;
                split_ship->back_ship.draw_debris[i]  = DEBRIS_NONE;
        } */

        // set up physics 
        physics_init( &split_ship->front_ship.phys_info );
        physics_init( &split_ship->back_ship.phys_info );
        split_ship->front_ship.phys_info.flags  |= (PF_ACCELERATES | PF_DEAD_DAMP);
        split_ship->back_ship.phys_info.flags |= (PF_ACCELERATES | PF_DEAD_DAMP);
        split_ship->front_ship.phys_info.side_slip_time_const = 10000.0f;
        split_ship->back_ship.phys_info.side_slip_time_const =  10000.0f;
        split_ship->front_ship.phys_info.rotdamp = 10000.0f;
        split_ship->back_ship.phys_info.rotdamp =  10000.0f;

        // set up explosion vel and relative velocities (assuming mass depends on length)
        float front_length = pm->maxs.z - split_ship->front_ship.cur_clip_plane_pt;
        float back_length  = split_ship->back_ship.cur_clip_plane_pt - pm->mins.z;
        float ship_length = front_length + back_length;
        split_ship->front_ship.length_left = front_length;
        split_ship->back_ship.length_left  = back_length;

        float expl_length_scale = (ship_length - 200.0f) / 2000.0f;
        // s_r_f effects speed of "wipe" and rotvel
        float speed_reduction_factor = (1.0f + 0.001f*parent_ship_obj->radius);
        float explosion_time = (3.0f + expl_length_scale + (frand()-0.5f)) * speed_reduction_factor;
        float long_length = max(front_length, back_length);
        float expl_vel = long_length / explosion_time;
        split_ship->front_ship.explosion_vel = expl_vel;
        split_ship->back_ship.explosion_vel  = -expl_vel;

        float rel_vel = (0.6f + 0.2f*frand()) * expl_vel * speed_reduction_factor;
        float front_vel = rel_vel * back_length / ship_length;
        float back_vel = -rel_vel * front_length / ship_length;
        // mprintf(("rel_vel %.1f, expl_vel %.1f\n", rel_vel, expl_vel));

        // set up rotational vel
        vector rotvel;
        vm_vec_rand_vec_quick(&rotvel);
        rotvel.z = 0.0f;
        vm_vec_normalize(&rotvel);
        vm_vec_scale(&rotvel, 0.15f / speed_reduction_factor);
        split_ship->front_ship.phys_info.rotvel = rotvel;
        vm_vec_copy_scale(&split_ship->back_ship.phys_info.rotvel, &rotvel, -(front_length*front_length)/(back_length*back_length));
        split_ship->front_ship.phys_info.rotvel.z = parent_ship_obj->phys_info.rotvel.z;
        split_ship->back_ship.phys_info.rotvel.z  = parent_ship_obj->phys_info.rotvel.z;


        // modify vel of each split ship based on rotvel of parent ship obj
        vector temp_rotvel = parent_ship_obj->phys_info.rotvel;
        temp_rotvel.z = 0.0f;
        vector vel_from_rotvel;
        vm_vec_crossprod(&vel_from_rotvel, &temp_rotvel, &split_ship->front_ship.local_pivot);
        //      vm_vec_scale_add2(&split_ship->front_ship.phys_info.vel, &vel_from_rotvel, 0.5f);
        vm_vec_crossprod(&vel_from_rotvel, &temp_rotvel, &split_ship->back_ship.local_pivot);
        //      vm_vec_scale_add2(&split_ship->back_ship.phys_info.vel, &vel_from_rotvel, 0.5f);

        // set up velocity and make initial fireballs and particles
        split_ship->front_ship.phys_info.vel = parent_ship_obj->phys_info.vel;
        split_ship->back_ship.phys_info.vel  = parent_ship_obj->phys_info.vel;
        maybe_fireball_wipe(&split_ship->front_ship, (int*)&split_ship->sound_handle);
        maybe_fireball_wipe(&split_ship->back_ship,  (int*)&split_ship->sound_handle);
        vm_vec_scale_add2(&split_ship->front_ship.phys_info.vel, &orient->fvec, front_vel);
        vm_vec_scale_add2(&split_ship->back_ship.phys_info.vel,  &orient->fvec, back_vel);

        // HANDLE LIVE DEBRIS - blow off if not already gone
        shipfx_maybe_create_live_debris_at_ship_death( parent_ship_obj );
}


static void half_ship_render_ship_and_debris(clip_ship* half_ship,ship *shipp)
{
        Assert( Split_ships_inited );

        polymodel *pm = model_get(shipp->modelnum);

        // get rotated clip plane normal and world coord of original ship center
        vector orig_ship_world_center, clip_plane_norm, model_clip_plane_pt, debris_clip_plane_pt;
        vm_vec_unrotate(&clip_plane_norm, &half_ship->clip_plane_norm, &half_ship->orient);
        vm_vec_unrotate(&orig_ship_world_center, &half_ship->model_center_disp_to_orig_center, &half_ship->orient);
        vm_vec_add2(&orig_ship_world_center, &half_ship->local_pivot);

        // *out_pivot = orig_ship_world_center;

        // get debris clip plane pt and draw debris
        vm_vec_unrotate(&debris_clip_plane_pt, &half_ship->model_center_disp_to_orig_center, &half_ship->orient);
        vm_vec_add2(&debris_clip_plane_pt, &half_ship->local_pivot);
        g3_start_user_clip_plane( &debris_clip_plane_pt, &clip_plane_norm);

        // set up render flags
        uint render_flags = MR_NORMAL;

        for (int i=0; i<pm->num_debris_objects; i++ )   {
                // draw DEBRIS_FREE in test only
                if (half_ship->draw_debris[i] == DEBRIS_DRAW) {
                        vector temp_pos = orig_ship_world_center;
                        vector tmp = {0.0f, 0.0f, 0.0f};
                        vector tmp1 = pm->submodel[pm->debris_objects[i]].offset;

                        // determine if explosion front has past debris piece
                        // 67 ~ dist expl moves in 2 frames -- maybe fraction works better
                        int is_live_debris = pm->submodel[pm->debris_objects[i]].is_live_debris;
                        int create_debris = 0;
                        // front ship
                        if (half_ship->explosion_vel > 0) {
                                if (half_ship->cur_clip_plane_pt > tmp1.z + pm->submodel[pm->debris_objects[i]].max.z - 0.1f*half_ship->explosion_vel) {
                                        create_debris = 1;
                                }
                                // is the debris visible
//                              if (half_ship->cur_clip_plane_pt > tmp1.z + pm->submodel[pm->debris_objects[i]].min.z - 0.5f*half_ship->explosion_vel) {
//                                      render_debris = 1;
//                              }
                        // back ship
                        } else {
                                if (half_ship->cur_clip_plane_pt < tmp1.z + pm->submodel[pm->debris_objects[i]].min.z - 0.1f*half_ship->explosion_vel) {
                                        create_debris = 1;
                                }
                                // is the debris visible
//                              if (half_ship->cur_clip_plane_pt < tmp1.z + pm->submodel[pm->debris_objects[i]].max.z - 0.5f*half_ship->explosion_vel) {
//                                      render_debris = 1;
//                              }
                        }

                        // Draw debris, but not live debris
                        if ( !is_live_debris ) {
                                model_find_world_point(&tmp, &tmp1, shipp->modelnum, -1, &half_ship->orient, &temp_pos);
                                submodel_render(shipp->modelnum, pm->debris_objects[i], &half_ship->orient, &tmp, render_flags);
                        }

                        // make free piece of debris
                        if ( create_debris ) {
                                half_ship->draw_debris[i] = DEBRIS_FREE;                // mark debris to not render with model
                                vector center_to_debris, debris_vel, radial_vel;
                                // check if last debris piece, ie, debris_count == 0
                                int debris_count = 0;
                                for (int j=0; j<pm->num_debris_objects; j++ ) {
                                        if (half_ship->draw_debris[j] == DEBRIS_DRAW) {
                                                debris_count++;
                                        }
                                } 
                                // do debris create here, but not for live debris
                                // debris vel (1) split ship vel (2) split ship rotvel (3) random
                                if ( !is_live_debris ) {
                                        object* debris_obj;
                                        debris_obj = debris_create(half_ship->parent_obj, shipp->modelnum, pm->debris_objects[i], &tmp, &half_ship->local_pivot, 1, 1.0f);
                                        // AL: make sure debris_obj isn't NULL!
                                        if ( debris_obj ) {
                                                vm_vec_scale(&debris_obj->phys_info.rotvel, 4.0f);
                                                debris_obj->orient = half_ship->orient;
                                                // if (debris_count > 0) {
                                                        //mprintf(( "base rotvel %.1f, debris rotvel mag %.2f\n", vm_vec_mag(&half_ship->phys_info.rotvel), vm_vec_mag(&debris_obj->phys_info.rotvel) ));
                                                        vm_vec_sub(&center_to_debris, &tmp, &half_ship->local_pivot);
                                                        vm_vec_crossprod(&debris_vel, &center_to_debris, &half_ship->phys_info.rotvel);
                                                        vm_vec_add2(&debris_vel, &half_ship->phys_info.vel);
                                                        vm_vec_copy_normalize(&radial_vel, &center_to_debris);
                                                        float radial_mag = 10.0f + 30.0f*frand();
                                                        vm_vec_scale_add2(&debris_vel, &radial_vel, radial_mag);
                                                        debris_obj->phys_info.vel = debris_vel;
                                                /* } else {
                                                        debris_obj->phys_info.vel = half_ship->phys_info.vel;
                                                        debris_obj->phys_info.rotvel = half_ship->phys_info.rotvel;
                                                } */
                                        }
                                }
                        }
                }
        }

        // get model clip plane pt and draw model
        vector temp;
        vm_vec_make(&temp, 0.0f, 0.0f, half_ship->cur_clip_plane_pt);
        vm_vec_unrotate(&model_clip_plane_pt, &temp, &half_ship->orient);
        vm_vec_add2(&model_clip_plane_pt, &orig_ship_world_center);
        g3_start_user_clip_plane( &model_clip_plane_pt, &clip_plane_norm );
        model_render(shipp->modelnum, &half_ship->orient, &orig_ship_world_center, render_flags);
}

void shipfx_large_blowup_level_init()
{
        split_ship_init_system();

        if(Ship_cannon_bitmap != -1){
                bm_unload(Ship_cannon_bitmap);
                Ship_cannon_bitmap = bm_load(SHIP_CANNON_BITMAP);
        }
}

// Returns 0 if couldn't init
int shipfx_large_blowup_init(ship *shipp)
{

        if ( !Split_ships_inited )      {
                split_ship_init_system();
        }

        int i;
        for (i=0; i<MAX_SPLIT_SHIPS; i++ )      {
                if ( Split_ships[i].used == 0 ) {
                        break;
                }
        }

        if ( i >= MAX_SPLIT_SHIPS )     {
                mprintf(( "Not enough split ship slots!! See John!\n" ));
                Int3();
                return 0;
        }

        Split_ships[i].used = 1;
        shipp->large_ship_blowup_index = i;

        split_ship_init(shipp, &Split_ships[i] );
        
        return 1;
}

// ----------------------------------------------------------------------------
// uses list of model z values with constant increment to find the radius of the 
// cross section at the current model z value
float get_model_cross_section_at_z(float z, polymodel* pm)
{
        if (pm->num_xc < 2) {
                return 0.0f;
        }

        float index, increment;
        increment = (pm->xc[pm->num_xc-1].z - pm->xc[0].z) / (float)(pm->num_xc - 1);
        index = (z - pm->xc[0].z) / increment;

        if (index < 0.5f) {
                return pm->xc[0].radius;
        } else if (index > (pm->num_xc - 1.0f - 0.5f)) {
                return pm->xc[pm->num_xc-1].radius;
        } else {
                int floor_index = (int)floor(index);
                int ceil_index  = (int)ceil(index);
                return max(pm->xc[ceil_index].radius, pm->xc[floor_index].radius);
        }
}

// returns how long sound has been playing
int get_sound_time_played(int snd_id, int handle)
{
        if (handle == -1) {
                return 100000;
        }

        int bits_per_sample, frequency;
        snd_get_format(snd_id, &bits_per_sample, &frequency);
        int time_left = snd_time_remaining(handle, bits_per_sample, frequency);
        int duration = snd_get_duration(snd_id);
        
        return (duration - time_left);
}

// sound manager for big ship sub explosions sounds.
// forces playing of sub-explosion sounds.  keeps track of active sounds, plays them for >= 750 ms
// when sound has played >= 750, sound is stopped and new instance is started 
void do_sub_expl_sound(float radius, vector* sound_pos, int* sound_handle)
{
        int sound_index, handle;
        // multiplier for range (near and far distances) to apply attenuation
        float sound_range = 1.0f + 0.0043f*radius;

        int handle_index = rand()%NUM_SUB_EXPL_HANDLES;
        //mprintf(("handle_index %d\n", *handle_index));

        // sound_index = get_sub_explosion_sound_index(handle_index);
        sound_index = SND_SHIP_EXPLODE_1;
        handle = sound_handle[handle_index];


        // mprintf(("dist to sound %.1f snd_indx: %d, h1: %d, h2: %d\n", vm_vec_dist(&Player_obj->pos, sound_pos), next_sound_index, sound_handle[0], sound_handle[1]));

        if (handle == -1) {
                // if no handle, get one
                sound_handle[handle_index] = snd_play_3d( &Snds[sound_index], sound_pos, &View_position, 0.0f, NULL, 0, 0.6f, SND_PRIORITY_MUST_PLAY, NULL, sound_range );
        } else if (!snd_is_playing(handle)) {
                // if sound not playing and old, get new one
                // I don't think will happen with SND_PRIORITY_MUST_PLAY
                if (get_sound_time_played(Snds[sound_index].id, handle) > 400) {
                        //mprintf(("sound not playing %d, time_played %d, stopped\n", handle, get_sound_time_played(Snds[sound_index].id, handle)));
                        snd_stop(sound_handle[handle_index]);
                        sound_handle[handle_index] = snd_play_3d( &Snds[sound_index], sound_pos, &View_position, 0.0f, NULL, 0, 0.6f, SND_PRIORITY_MUST_PLAY, NULL, sound_range );
                }
        } else if (get_sound_time_played(Snds[sound_index].id, handle) > 750) {
                //mprintf(("time %f, cur sound %d time_played %d num sounds %d\n", f2fl(Missiontime), handle_index, get_sound_time_played(Snds[sound_index].id, handle), snd_num_playing() ));
                sound_handle[handle_index] = snd_play_3d( &Snds[sound_index], sound_pos, &View_position, 0.0f, NULL, 0, 0.6f, SND_PRIORITY_MUST_PLAY, NULL, sound_range );
        }
}

// maybe create a fireball along model clip plane
// also maybe plays explosion sound
static void maybe_fireball_wipe(clip_ship* half_ship, int* sound_handle)
{
        // maybe make fireball to cover wipe.
        if ( timestamp_elapsed(half_ship->next_fireball) ) {
                if ( half_ship->length_left > 0.2f*fl_abs(half_ship->explosion_vel) )   {

                        polymodel* pm = model_get(Ships[half_ship->parent_obj->instance].modelnum);

                        vector model_clip_plane_pt, orig_ship_world_center, temp;

                        vm_vec_unrotate(&orig_ship_world_center, &half_ship->model_center_disp_to_orig_center, &half_ship->orient);
                        vm_vec_add2(&orig_ship_world_center, &half_ship->local_pivot);

                        vm_vec_make(&temp, 0.0f, 0.0f, half_ship->cur_clip_plane_pt);
                        vm_vec_unrotate(&model_clip_plane_pt, &temp, &half_ship->orient);
                        vm_vec_add2(&model_clip_plane_pt, &orig_ship_world_center);
                        vm_vec_rand_vec_quick(&temp);
                        vm_vec_scale(&temp, 0.1f*frand());
                        vm_vec_add2(&model_clip_plane_pt, &temp);

                        float rad = get_model_cross_section_at_z(half_ship->cur_clip_plane_pt, pm);
                        if (rad < 1) {
                                rad = half_ship->parent_obj->radius * frand_range(0.4f, 0.6f);
                        } else {
                                // make fireball radius (1.5 +/- .1) * model_cross_section value
                                rad *= frand_range(1.4f, 1.6f);
                        }

                        rad *= 1.5f;
                        rad = min(rad, half_ship->parent_obj->radius);

                        // mprintf(("xc %.1f model %.1f\n", rad, half_ship->parent_obj->radius*0.25));
                        int fireball_type = FIREBALL_EXPLOSION_LARGE1 + rand()%FIREBALL_NUM_LARGE_EXPLOSIONS;
                        int low_res_fireballs = Bs_exp_fire_low;
                        fireball_create(&model_clip_plane_pt, fireball_type, OBJ_INDEX(half_ship->parent_obj), rad, 0, &half_ship->parent_obj->phys_info.vel, 0.0f, -1, NULL, low_res_fireballs);

                        // start the next fireball up (3-4 per frame) + 30%
                        int time_low, time_high;
                        time_low = int(650 * Bs_exp_fire_time_mult);
                        time_high = int(900 * Bs_exp_fire_time_mult);
                        half_ship->next_fireball = timestamp_rand(time_low, time_high);

                        // do sound
                        do_sub_expl_sound(half_ship->parent_obj->radius, &model_clip_plane_pt, sound_handle);

                        // do particles
                        particle_emitter        pe;

                        pe.num_low = 40;                                        // Lowest number of particles to create
                        pe.num_high = 80;                               // Highest number of particles to create
                        pe.pos = model_clip_plane_pt;   // Where the particles emit from
                        pe.vel = half_ship->phys_info.vel;              // Initial velocity of all the particles

#ifdef FS2_DEMO
                        float range = 1.0f + 0.002f*half_ship->parent_obj->radius * 5.0f;
#else 
                        float range = 1.0f + 0.002f*half_ship->parent_obj->radius;
#endif

#ifdef FS2_DEMO
                        pe.min_life = 2.0f*range;                               // How long the particles live
                        pe.max_life = 10.0f*range;                              // How long the particles live
#else
                        pe.min_life = 0.5f*range;                               // How long the particles live
                        pe.max_life = 6.0f*range;                               // How long the particles live
#endif
                        pe.normal = vmd_x_vector;               // What normal the particle emit around
                        pe.normal_variance = 2.0f;              //      How close they stick to that normal 0=on normal, 1=180, 2=360 degree
                        pe.min_vel = 0.0f;                              // How fast the slowest particle can move
                        pe.max_vel = half_ship->explosion_vel;                          // How fast the fastest particle can move

#ifdef FS2_DEMO
                        float scale = half_ship->parent_obj->radius * 0.02f;
#else
                        float scale = half_ship->parent_obj->radius * 0.01f;
#endif
                        pe.min_rad = 0.5f*scale;                                // Min radius
                        pe.max_rad = 1.5f*scale;                                // Max radius

                        particle_emit( &pe, PARTICLE_SMOKE2, 0, range );

                } else {
                        // time out forever
                        half_ship->next_fireball = timestamp(-1);
                }
        }
}


// Returns 1 when explosion is done
int shipfx_large_blowup_do_frame(ship *shipp, float frametime)
{
        // DAVE:  I made this not do any movement just to try to get things working...
        // return 0;

        Assert( Split_ships_inited );
        Assert( shipp->large_ship_blowup_index > -1 );

        split_ship *the_split_ship = &Split_ships[shipp->large_ship_blowup_index];
        Assert( the_split_ship->used );         // Get John

        // Do fireballs, particles, shockwave here
        // Note parent ship is still valid, vel and pos updated in obj_move_all

        if ( timestamp_elapsed(the_split_ship->explosion_flash_timestamp) ) {
                if ( !the_split_ship->explosion_flash_started ) {
                        object* objp = &Objects[shipp->objnum];
                        if (objp->flags & OF_WAS_RENDERED) {
                                float excess_dist = vm_vec_dist(&Player_obj->pos, &objp->pos) - 2.0f*objp->radius - Player_obj->radius;
                                float intensity = 1.0f - 0.1f*excess_dist / objp->radius;

                                if (intensity > 1) {
                                        intensity = 1.0f;
                                }

                                if (intensity > 0.1f) {
                                        // big_explosion_flash(intensity);
                                }
                        }
                        the_split_ship->explosion_flash_started = 1;
                }
        }

        physics_sim(&the_split_ship->front_ship.local_pivot, &the_split_ship->front_ship.orient, &the_split_ship->front_ship.phys_info, frametime);
        physics_sim(&the_split_ship->back_ship.local_pivot,  &the_split_ship->back_ship.orient,  &the_split_ship->back_ship.phys_info,  frametime);
        the_split_ship->front_ship.length_left -= the_split_ship->front_ship.explosion_vel*frametime;
        the_split_ship->back_ship.length_left  += the_split_ship->back_ship.explosion_vel *frametime;
        the_split_ship->front_ship.cur_clip_plane_pt += the_split_ship->front_ship.explosion_vel*frametime;
        the_split_ship->back_ship.cur_clip_plane_pt  += the_split_ship->back_ship.explosion_vel *frametime;

        float length_left = max( the_split_ship->front_ship.length_left, the_split_ship->back_ship.length_left );

        //      mprintf(( "Blowup frame, dist = %.1f \n", length_left ));

        if ( length_left < 0 )  {
                the_split_ship->used = 0;
                return 1;
        }

        maybe_fireball_wipe(&the_split_ship->front_ship, (int*)&the_split_ship->sound_handle);
        maybe_fireball_wipe(&the_split_ship->back_ship,  (int*)&the_split_ship->sound_handle);
        return 0;
}

void shipfx_large_blowup_render(ship* shipp)
{
// This actually renders the original model like it should render.
//      object *objp = &Objects[shipp->objnum];
//      model_render( shipp->modelnum, &objp->orient, &objp->pos, MR_NORMAL );
//      return;

        Assert( Split_ships_inited );
        Assert( shipp->large_ship_blowup_index > -1 );

        split_ship *the_split_ship = &Split_ships[shipp->large_ship_blowup_index];
        Assert( the_split_ship->used );         // Get John

        // vector front_global_pivot, back_global_pivot;

        if (the_split_ship->front_ship.length_left > 0) {
                half_ship_render_ship_and_debris(&the_split_ship->front_ship,shipp);
        }

        if (the_split_ship->back_ship.length_left > 0) {
                half_ship_render_ship_and_debris(&the_split_ship->back_ship,shipp);
        }

        g3_stop_user_clip_plane();                      
}


// ================== DO THE ELECTRIC ARCING STUFF =====================
// Creates any new ones, moves old ones.

#define MAX_ARC_LENGTH_PERCENTAGE 0.25f

#define MAX_EMP_ARC_TIMESTAMP            (150.0f)

void shipfx_do_damaged_arcs_frame( ship *shipp )
{
        int i;
        int should_arc;
        object *obj = &Objects[shipp->objnum];
        ship_info * sip = &Ship_info[shipp->ship_info_index];

        should_arc = 1;

        float damage = obj->hull_strength / sip->initial_hull_strength; 

        if (damage < 0) {
                damage = 0.0f;
        }

        // don't draw an arc based on damage
        if ( damage > 0.30f )   {
                // Don't do spark.
                should_arc = 0;
        }

        // we should draw an arc
        if( shipp->emp_intensity > 0.0f){
                should_arc = 1;
        }

        // Kill off old sparks
        for(i=0; i<MAX_SHIP_ARCS; i++){
                if(timestamp_valid(shipp->arc_timestamp[i]) && timestamp_elapsed(shipp->arc_timestamp[i])){                     
                        shipp->arc_timestamp[i] = timestamp(-1);
                }
        }

        // if we shouldn't draw an arc, return
        if(!should_arc){
                return;
        }

        if (!timestamp_valid(shipp->arc_next_time))     {
                // start the next fireball up in the next 10 seconds or so... 
                int freq;
                
                // if the emp effect is active
                if(shipp->emp_intensity > 0.0f){
                        freq = fl2i(MAX_EMP_ARC_TIMESTAMP);
                }
                // otherwise if we're arcing based upon damage
                else {
                        freq = fl2i((damage+0.1f)*5000.0f);
                }

                // set the next arc time
                shipp->arc_next_time = timestamp_rand(freq*2,freq*4);
        }

        if ( timestamp_elapsed(shipp->arc_next_time) )  {

                shipp->arc_next_time = timestamp(-1);           // invalid, so it gets restarted next frame

                //mprintf(( "Creating new ship arc!\n" ));

                int n, n_arcs = ((rand()>>5) % 3)+1;            // Create 1-3 sparks

                vector v1, v2, v3, v4;
                submodel_get_two_random_points( shipp->modelnum, -1, &v1, &v2 );
                submodel_get_two_random_points( shipp->modelnum, -1, &v3, &v4 );

                // For large ships, cap the length to be 25% of max radius
                if ( obj->radius > 200.0f )     {
                        float max_dist = obj->radius * MAX_ARC_LENGTH_PERCENTAGE;
                        
                        vector tmp;
                        float d;

                        // Cap arc 2->1
                        vm_vec_sub( &tmp, &v1, &v2 );
                        d = vm_vec_mag_quick( &tmp );
                        if ( d > max_dist )     {
                                vm_vec_scale_add( &v1, &v2, &tmp, max_dist / d );
                        }

                        // Cap arc 2->3
                        vm_vec_sub( &tmp, &v3, &v2 );
                        d = vm_vec_mag_quick( &tmp );
                        if ( d > max_dist )     {
                                vm_vec_scale_add( &v3, &v2, &tmp, max_dist / d );
                        }


                        // Cap arc 2->4
                        vm_vec_sub( &tmp, &v4, &v2 );
                        d = vm_vec_mag_quick( &tmp );
                        if ( d > max_dist )     {
                                vm_vec_scale_add( &v4, &v2, &tmp, max_dist / d );
                        }
                        
                }
                
                n = 0;

//              int a = 100, b = 1000;
                float factor = 1.0f + 0.0025f*obj->radius;
                int a = (int) (factor*100.0f);
                int b = (int) (factor*1000.0f);
                int lifetime = (myrand()%((b)-(a)+1))+(a);

                // Create the arc effects
                for (i=0; i<MAX_SHIP_ARCS; i++ )        {
                        if ( !timestamp_valid( shipp->arc_timestamp[i] ) )      {
                                //shipp->arc_timestamp[i] = timestamp_rand(400,1000);   // live up to a second
                                shipp->arc_timestamp[i] = timestamp(lifetime);  // live up to a second

                                switch( n )     {
                                case 0:
                                        shipp->arc_pts[i][0] = v1;
                                        shipp->arc_pts[i][1] = v2;
                                        break;
                                case 1:
                                        shipp->arc_pts[i][0] = v2;
                                        shipp->arc_pts[i][1] = v3;
                                        break;

                                case 2:
                                        shipp->arc_pts[i][0] = v2;
                                        shipp->arc_pts[i][1] = v4;
                                        break;

                                default:
                                        Int3();
                                }

                                // determine what kind of arc to create
                                if(shipp->emp_intensity > 0.0f){
                                        shipp->arc_type[i] = MARC_TYPE_EMP;
                                } else {
                                        shipp->arc_type[i] = MARC_TYPE_NORMAL;
                                }
                                        
                                n++;
                                if ( n == n_arcs )
                                        break;  // Don't need to create anymore
                        }
        
                        // rotate v2 out of local coordinates into world.
                        // Use v2 since it is used in every bolt.  See above switch().
                        vector snd_pos;
                        vm_vec_unrotate(&snd_pos, &v2, &obj->orient);
                        vm_vec_add2(&snd_pos, &obj->pos );

                        //Play a sound effect
                        if ( lifetime > 750 )   {
                                // 1.00 second effect
                                snd_play_3d( &Snds[SND_DEBRIS_ARC_05], &snd_pos, &View_position, obj->radius );
                        } else if ( lifetime >  500 )   {
                                // 0.75 second effect
                                snd_play_3d( &Snds[SND_DEBRIS_ARC_04], &snd_pos, &View_position, obj->radius );
                        } else if ( lifetime >  250 )   {
                                // 0.50 second effect
                                snd_play_3d( &Snds[SND_DEBRIS_ARC_03], &snd_pos, &View_position, obj->radius );
                        } else if ( lifetime >  100 )   {
                                // 0.25 second effect
                                snd_play_3d( &Snds[SND_DEBRIS_ARC_02], &snd_pos, &View_position, obj->radius );
                        } else {
                                // 0.10 second effect
                                snd_play_3d( &Snds[SND_DEBRIS_ARC_01], &snd_pos, &View_position, obj->radius );
                        }
                }
        }

        // maybe move arc points around
        for (i=0; i<MAX_SHIP_ARCS; i++ )        {
                if ( timestamp_valid( shipp->arc_timestamp[i] ) )       {
                        if ( !timestamp_elapsed( shipp->arc_timestamp[i] ) )    {                                                       
                                // Maybe move a vertex....  20% of the time maybe?
                                int mr = myrand();
                                if ( mr < RAND_MAX/5 )  {
                                        vector v1, v2;
                                        submodel_get_two_random_points( shipp->modelnum, -1, &v1, &v2 );

                                        vector static_one;

                                        if ( mr % 2 )   {
                                                static_one = shipp->arc_pts[i][0];
                                        } else {
                                                static_one = shipp->arc_pts[i][1];
                                        }

                                        // For large ships, cap the length to be 25% of max radius
                                        if ( obj->radius > 200.0f )     {
                                                float max_dist = obj->radius * MAX_ARC_LENGTH_PERCENTAGE;
                                                
                                                vector tmp;
                                                float d;

                                                // Cap arc 2->1
                                                vm_vec_sub( &tmp, &v1, &static_one );
                                                d = vm_vec_mag_quick( &tmp );
                                                if ( d > max_dist )     {
                                                        vm_vec_scale_add( &v1, &static_one, &tmp, max_dist / d );
                                                }
                                        }

                                        shipp->arc_pts[i][mr % 2] = v1;
                                }
                        }
                }
        }
}

int l_cruiser_count = 1;
int l_big_count = 2;
int l_huge_count = 3;
float l_max_radius = 3000.0f;
void shipfx_do_lightning_frame( ship *shipp )
{
        /*
        ship_info *sip;
        object *objp;
        int stamp, count;
        vector v1, v2, n1, n2, temp, temp2;
        bolt_info binfo;

        // sanity checks
        Assert(shipp != NULL);
        if(shipp == NULL){
                return;
        } 
        Assert(shipp->ship_info_index >= 0);
        if(shipp->ship_info_index < 0){
                return;
        }       
        Assert(shipp->objnum >= 0);
        if(shipp->objnum < 0){
                return;
        }       

        // get some pointers
        sip = &Ship_info[shipp->ship_info_index];
        objp = &Objects[shipp->objnum]; 

        // if this is not a nebula mission, don't do anything
        if(!(The_mission.flags & MISSION_FLAG_FULLNEB)){
                shipp->lightning_stamp = -1;
                return;
        }
        
        // if this not a cruiser or big ship
        if(!((sip->flags & SIF_CRUISER) || (sip->flags & SIF_BIG_SHIP) || (sip->flags & SIF_HUGE_SHIP))){
                shipp->lightning_stamp = -1;
                return;
        }

        // determine stamp and count values
        if(sip->flags & SIF_CRUISER){
                stamp = (int)((float)(Nebl_cruiser_min + ((Nebl_cruiser_max - Nebl_cruiser_min) * Nebl_intensity)) * frand_range(0.8f, 1.1f));
                count = l_cruiser_count;
        } 
        else {
                if(sip->flags & SIF_HUGE_SHIP){
                        stamp = (int)((float)(Nebl_supercap_min + ((Nebl_supercap_max - Nebl_supercap_min) * Nebl_intensity)) * frand_range(0.8f, 1.1f));
                        count = l_huge_count;
                } else {
                        stamp = (int)((float)(Nebl_cap_min + ((Nebl_cap_max - Nebl_cap_min) * Nebl_intensity)) * frand_range(0.8f, 1.1f));
                        count = l_big_count;
                }
        }

        // if his timestamp is unset
        if(shipp->lightning_stamp == -1){
                shipp->lightning_stamp = timestamp(stamp);
                return;
        }
        // if his timestamp is currently unelapsed
        if(!timestamp_elapsed(shipp->lightning_stamp)){
                return;
        }

        mprintf(("SHIP BOLT\n"));

        // restamp him first
        shipp->lightning_stamp = timestamp(stamp);

        // ah, now we can create some lightning bolts
        count = (int)frand_range(0.0f, (float)count);
        while(count > 0){
                // get 2 points on the hull of the ship
                submodel_get_two_random_points(shipp->modelnum, 0, &v1, &v2, &n1, &n2);         

                // make up to 2 bolts
                if(objp->radius > l_max_radius){
                        vm_vec_scale_add(&temp2, &v1, &n1, l_max_radius);
                } else {
                        vm_vec_scale_add(&temp2, &v1, &n1, objp->radius);
                }
                vm_vec_unrotate(&temp, &temp2, &objp->orient);
                vm_vec_add2(&temp, &objp->pos);
                vm_vec_unrotate(&temp2, &v1, &objp->orient);
                vm_vec_add2(&temp2, &objp->pos);

                // create the bolt
                binfo.start = temp;
                binfo.strike = temp2;
                binfo.num_strikes = 3;
                binfo.noise = 0.045f;
                binfo.life = 375;
                binfo.delay = (int)frand_range(0.0f, 1600.0f);
                nebl_bolt(&binfo);
                count--;
        
                // done
                if(count <= 0){
                        break;
                }

                // one more             
                if(objp->radius > l_max_radius){
                        vm_vec_scale_add(&temp2, &v2, &n2, l_max_radius);
                } else {
                        vm_vec_scale_add(&temp2, &v2, &n2, objp->radius);
                }
                vm_vec_unrotate(&temp, &temp2, &objp->orient);
                vm_vec_add2(&temp, &objp->pos);
                vm_vec_unrotate(&temp2, &v2, &objp->orient);
                vm_vec_add2(&temp2, &objp->pos);

                // create the bolt
                binfo.start = temp;
                binfo.strike = temp2;
                binfo.num_strikes = 3;
                binfo.noise = 0.045f;
                binfo.life = 375;
                binfo.delay = (int)frand_range(0.0f, 1600.0f);
                nebl_bolt(&binfo);              
                count--;
        }
        */
}

// do all shockwaves for a ship blowing up
void shipfx_do_shockwave_stuff(ship *shipp, shockwave_create_info *sci)
{
        ship_info *sip;
        object *objp;
        polymodel *pm;
        vector temp, dir, shockwave_pos;
        vector head = vmd_zero_vector;
        vector tail = vmd_zero_vector;  
        float len, step, cur;
        int idx;

        // sanity checks
        Assert(shipp != NULL);
        if(shipp == NULL){
                return;
        } 
        Assert(shipp->ship_info_index >= 0);
        if(shipp->ship_info_index < 0){
                return;
        }       
        Assert(shipp->objnum >= 0);
        if(shipp->objnum < 0){
                return;
        }
        Assert(sci != NULL);
        if (sci == NULL) {
                return;
        }

        // get some pointers
        sip = &Ship_info[shipp->ship_info_index];
        objp = &Objects[shipp->objnum]; 

        Assert(sip->shockwave_count > 0);
        if(sip->shockwave_count <= 0){
                return;
        }

        // get vectors at the head and tail of the object, dead center          
        pm = model_get(shipp->modelnum);
        if(pm == NULL){
                return;
        }
        head.x = pm->submodel[0].offset.x;
        head.y = pm->submodel[0].offset.y;
        head.z = pm->maxs.z;

        tail.x = pm->submodel[0].offset.x;
        tail.y = pm->submodel[0].offset.y;
        tail.z = pm->mins.z;

        // transform the vectors into world coords
        vm_vec_unrotate(&temp, &head, &objp->orient);
        vm_vec_add(&head, &temp, &objp->pos);
        vm_vec_unrotate(&temp, &tail, &objp->orient);
        vm_vec_add(&tail, &temp, &objp->pos);

        // now create as many shockwaves as needed
        vm_vec_sub(&dir, &head, &tail);
        len = vm_vec_mag(&dir);
        step = 1.0f / ((float)sip->shockwave_count + 1.0f);
        cur = step;
        for(idx=0; idx<sip->shockwave_count; idx++){
                // get the shockwave position           
                temp = dir;
                vm_vec_scale(&temp, cur);
                vm_vec_add(&shockwave_pos, &tail, &temp);

                // if knossos device, make shockwave in center
                if (Ship_info[shipp->ship_info_index].flags & SIF_KNOSSOS_DEVICE) {
                        shockwave_pos = Objects[shipp->objnum].pos;
                }

                // create the shockwave
                shockwave_create_info sci2;
                sci2.blast = (sci->blast / (float)sip->shockwave_count) * frand_range(0.75f, 1.25f);
                sci2.damage = (sci->damage / (float)sip->shockwave_count) * frand_range(0.75f, 1.25f);
                sci2.inner_rad = sci->inner_rad;
                sci2.outer_rad = sci->outer_rad;
                sci2.speed = sci->speed * frand_range(0.75f, 1.25f);
                sci2.rot_angle = frand_range(0.0f, 359.0f);

                shockwave_create(shipp->objnum, &shockwave_pos, &sci2, SW_SHIP_DEATH, (int)frand_range(0.0f, 350.0f));
                // shockwave_create(shipp->objnum, &objp->pos, sip->shockwave_speed, sip->inner_rad, sip->outer_rad, sip->damage, sip->blast, SW_SHIP_DEATH);

                // next shockwave
                cur += step;
        }
}

int Wash_on = 1;
DCF_BOOL(engine_wash, Wash_on);
#define ENGINE_WASH_CHECK_INTERVAL              250     // (4x sec)
// Do engine wash effect for ship
// Assumes length of engine wash is greater than radius of engine wash hemisphere
void engine_wash_ship_process(ship *shipp)
{
        int idx, j;             
        object *objp, *ship_objp, *max_ship_intensity_objp;
        int started_with_no_wash = shipp->wash_intensity <= 0 ? 1 : 0;

        if (!Wash_on) {
                return;
        }

        Assert(shipp != NULL);
        Assert(shipp->objnum >= 0);
        objp = &Objects[shipp->objnum];
        ship_obj *so;
        ship_objp = NULL;

        vector world_thruster_pos, world_thruster_norm, apex, thruster_to_ship, apex_to_ship, temp;
        float dist_sqr, inset_depth, dot_to_ship, max_ship_intensity;
        polymodel *pm;

        float max_wash_dist, half_angle, radius_mult;

        // if this is not a fighter or bomber, we don't care
        if ((objp->type != OBJ_SHIP) || !(Ship_info[shipp->ship_info_index].flags & (SIF_FIGHTER|SIF_BOMBER)) ) {
                return;
        }

        // is it time to check for engine wash 
        int time_to_next_hit = timestamp_until(shipp->wash_timestamp);
        if (time_to_next_hit < 0) {
                if (time_to_next_hit < -ENGINE_WASH_CHECK_INTERVAL) {
                        time_to_next_hit = 0;
                }

                // keep interval constant independent of framerate
                shipp->wash_timestamp = timestamp(ENGINE_WASH_CHECK_INTERVAL + time_to_next_hit);

                // initialize wash params
                shipp->wash_intensity = 0.0f;
                vm_vec_zero(&shipp->wash_rot_axis);
                max_ship_intensity_objp = NULL;
                max_ship_intensity = 0;
        } else {
                return;
        }

        // only do damage if we're within half of the max wash distance
        int do_damage = 0;

        // go thru Ship_used_list and check if we're in wash from CAP or SUPERCAP (SIF_HUGE)
        for (so = GET_FIRST(&Ship_obj_list); so != END_OF_LIST(&Ship_obj_list); so = GET_NEXT(so)) {
                ship_objp = &Objects[so->objnum];

                // don't do small ships
                if ( (Ship_info[Ships[ship_objp->instance].ship_info_index].flags & SIF_SMALL_SHIP) ) {
                        continue;
                }

                pm = model_get(Ships[ship_objp->instance].modelnum);
                float ship_intensity = 0;

                // if engines disabled, no engine wash
                if (ship_get_subsystem_strength(&Ships[ship_objp->instance], SUBSYSTEM_ENGINE) < 0.01) {
                        continue;
                }

                float   speed_scale;
                if (ship_objp->phys_info.speed > 20.0f)
                        speed_scale = 1.0f;
                else
                        speed_scale = ship_objp->phys_info.speed/20.0f;

                for (idx = 0; idx < pm->n_thrusters; idx++) {
                        thruster_bank *bank = &pm->thrusters[idx];

                        // check if thruster bank has engine wash
                        if (bank->wash_info_index < 0) {
                                // if huge, give default engine wash
                                if (Ship_info[Ships[ship_objp->instance].ship_info_index].flags & SIF_HUGE_SHIP) {
                                        bank->wash_info_index = 0;
                                        nprintf(("wash", "Adding default engine wash to ship %s", Ship_info[Ships[ship_objp->instance].ship_info_index].name));
                                } else {
                                        continue;
                                }
                        }

                        engine_wash_info *ewp = &Engine_wash_info[bank->wash_info_index];
                        half_angle = ewp->angle;
                        radius_mult = ewp->radius_mult;

                        for (j=0; j<bank->num_slots; j++) {
                                // get world pos of thruster
                                vm_vec_unrotate(&world_thruster_pos, &bank->pnt[j], &ship_objp->orient);
                                vm_vec_add2(&world_thruster_pos, &ship_objp->pos);
                                
                                // get world norm of thruster;
                                vm_vec_unrotate(&world_thruster_norm, &bank->norm[j], &ship_objp->orient);

                                // get vector from thruster to ship
                                vm_vec_sub(&thruster_to_ship, &objp->pos, &world_thruster_pos);

                                // check if on back side of thruster
                                dot_to_ship = vm_vec_dotprod(&thruster_to_ship, &world_thruster_norm);
                                if (dot_to_ship > 0) {

                                        // get max wash distance
                                        max_wash_dist = max(ewp->length, bank->radius[j]*ewp->radius_mult);

                                        // check if within dist range
                                        dist_sqr = vm_vec_mag_squared(&thruster_to_ship);
                                        if (dist_sqr < max_wash_dist*max_wash_dist) {

                                                // check if inside the sphere
                                                if (dist_sqr < radius_mult*radius_mult*bank->radius[j]*bank->radius[j]) {
                                                        vm_vec_crossprod(&temp, &world_thruster_norm, &thruster_to_ship);
                                                        vm_vec_scale_add2(&shipp->wash_rot_axis, &temp, dot_to_ship / dist_sqr);
//                                                      shipp->wash_intensity += (1.0f - dist_sqr / (max_wash_dist*max_wash_dist));
                                                        ship_intensity += (1.0f - dist_sqr / (max_wash_dist*max_wash_dist));
                                                        if (!do_damage) {
                                                                if (dist_sqr < 0.25 * max_wash_dist * max_wash_dist) {
                                                                        do_damage = 1;
                                                                }
                                                        }
                                                } else {
                                                        // check if inside cone - first fine apex of cone
                                                        inset_depth = float(bank->radius[j] / tan(half_angle));
                                                        vm_vec_scale_add(&apex, &world_thruster_pos, &world_thruster_norm, -inset_depth);
                                                        vm_vec_sub(&apex_to_ship, &objp->pos, &apex);
                                                        vm_vec_normalize(&apex_to_ship);

                                                        // check if inside cone angle
                                                        if (vm_vec_dotprod(&apex_to_ship, &world_thruster_norm) > cos(half_angle)) {
                                                                vm_vec_crossprod(&temp, &world_thruster_norm, &thruster_to_ship);
                                                                vm_vec_scale_add2(&shipp->wash_rot_axis, &temp, dot_to_ship / dist_sqr);
//                                                              shipp->wash_intensity += (1.0f - dist_sqr / (max_wash_dist*max_wash_dist));
                                                                ship_intensity += (1.0f - dist_sqr / (max_wash_dist*max_wash_dist));
                                                                if (!do_damage) {
                                                                        if (dist_sqr < 0.25 * max_wash_dist * max_wash_dist) {
                                                                                do_damage = 1;
                                                                        }
                                                                }
                                                        }
                                                }
                                        }
                                }
                        }
                }
                shipp->wash_intensity += ship_intensity * speed_scale;
                if (ship_intensity > max_ship_intensity) {
                        max_ship_intensity = ship_intensity;
                        max_ship_intensity_objp = ship_objp;
                }
        }

        // apply damage at rate of 1%/sec
        if (shipp->wash_intensity > 0) {
                Assert(max_ship_intensity_objp != NULL);

                nprintf(("wash", "Wash intensity %.2f\n", shipp->wash_intensity));

                float damage;
                if (!do_damage) {
                        damage = 0;
                } else {
                        damage = (0.001f * 0.003f * ENGINE_WASH_CHECK_INTERVAL * Ship_info[shipp->ship_info_index].initial_hull_strength * shipp->wash_intensity);
                }

                ship_apply_wash_damage(&Objects[shipp->objnum], max_ship_intensity_objp, damage);

                // if we had no wash before now, add the wash object sound
                if(started_with_no_wash){
                        if(shipp != Player_ship){
                                obj_snd_assign(shipp->objnum, SND_ENGINE_WASH, &vmd_zero_vector, 1);
                        } else {                                
                                Player_engine_wash_loop = snd_play_looping( &Snds[SND_ENGINE_WASH], 0.0f , -1, -1, 1.0f);
                        }
                }
        } 
        // if we've got no wash, kill any wash object sounds from this guy
        else {
                if(shipp != Player_ship){
                        obj_snd_delete(shipp->objnum, SND_ENGINE_WASH);
                } else {
                        snd_stop(Player_engine_wash_loop);
                        Player_engine_wash_loop = -1;
                }
        }
}

// engine wash level init
void shipfx_engine_wash_level_init()
{
        Player_engine_wash_loop = -1;
}

// pause engine wash sounds
void shipfx_stop_engine_wash_sound()
{
        if(Player_engine_wash_loop != -1){
                snd_stop(Player_engine_wash_loop);
                Player_engine_wash_loop = -1;
        }
}