2 * Copyright (C) Volition, Inc. 1999. All rights reserved.
4 * All source code herein is the property of Volition, Inc. You may not sell
5 * or otherwise commercially exploit the source or things you created based on
10 * $Logfile: /Freespace2/code/Physics/Physics.h $
15 * Clues to the meaning of life on Shivan planet Sphlighesphlaightseh
18 * Revision 1.2 2002/06/09 04:41:14 relnev
19 * added copyright header
21 * Revision 1.1.1.1 2002/05/03 03:28:12 root
25 * 6 8/13/99 10:49a Andsager
26 * Knossos and HUGE ship warp out. HUGE ship warp in. Stealth search
27 * modes dont collide big ships.
29 * 5 7/03/99 5:50p Dave
30 * Make rotated bitmaps draw properly in padlock views.
32 * 4 5/11/99 10:16p Andsager
33 * First pass on engine wash effect. Rotation (control input), damage,
36 * 3 3/19/99 9:51a Dave
37 * Checkin to repair massive source safe crash. Also added support for
38 * pof-style nebulae, and some new weapons code.
40 * 2 10/07/98 10:53a Dave
43 * 1 10/07/98 10:50a Dave
45 * 49 6/30/98 2:23p Dave
46 * Revised object update system. Removed updates for all weapons. Put
47 * button info back into control info packet.
49 * 48 3/12/98 5:21p Andsager
50 * Optimize physics for lasers and dumbfire missiles
52 * 47 2/03/98 6:01p Andsager
53 * Fix excessive rotvel in debris_create. Check using physics function
56 * 46 12/29/97 5:10p Allender
57 * fixed problems with speed not being reported properly in multiplayer
58 * games. Made read_flying_controls take frametime as a parameter. More
59 * ship/weapon select stuff
61 * 45 12/02/97 11:17p Andsager
62 * Added reduced_damp_decay timestamp.
64 * 44 11/17/97 5:15p Andsager
66 * 43 9/09/97 10:14p Andsager
68 * 42 9/04/97 5:09p Andsager
69 * implement physics using moment of inertia and mass (from BSPgen).
70 * Added to phys_info struct. Updated ship_info, polymodel structs.
71 * Updated weapon ($Mass and $Force) and ship ($Mass -> $Density) tables
73 * 41 8/29/97 10:13a Allender
74 * work on server/client prediction code -- doesn't work too well. Made
75 * all clients simulate their own orientation with the server giving
76 * corrections every so often.
78 * 40 8/19/97 9:56a John
79 * new thruster effect fairly functional
81 * 39 8/11/97 9:50a Allender
82 * fixed afterburner snafu
84 * 38 8/08/97 9:59a Allender
85 * added afterburner code into multiplayer. Required adding a new physics
86 * info flag to indicate afterburners ready to fire. (needed for
87 * multiplayer). Removed some now unused variables in afterburner.cpp
89 * 37 7/31/97 12:44p Andsager
91 * 36 7/27/97 5:14p Lawrance
92 * add afterburners to the player control info
94 * 35 7/25/97 9:07a Andsager
95 * modified apply_whack
97 * 34 7/23/97 5:10p Andsager
98 * Enhanced shockwave effect with shake based on blast force.
100 * 33 7/22/97 2:40p Andsager
101 * shockwaves now cause proper rotation of ships
103 * 32 7/21/97 4:12p Mike
104 * Two ships move as one while docked, including physics whacks. Spin of
105 * objects when killed based on speed.
107 * 31 7/16/97 11:53a Andsager
109 * 30 7/15/97 12:03p Andsager
112 * 29 7/11/97 11:54a John
113 * added rotated 3d bitmaps.
115 * 28 6/26/97 12:37p Allender
116 * added debug laser back in
118 * 27 5/08/97 11:42a Allender
119 * re-ordered game loop (again). Player weapons now created in simulation
120 * loop of code, not immediately.
122 * 26 4/17/97 10:02a Lawrance
123 * allow ship shaking for ABURN_DECAY_TIME after afterburners cut out
125 * 25 4/16/97 10:48p Mike
127 * Made afterburner engagement a bit in physics flags, removed from ship
128 * flags, removed a parameter to physics_read_flying_controls().
130 * 24 4/10/97 3:20p Mike
131 * Change hull damage to be like shields.
133 * 23 3/04/97 3:10p Mike
134 * Intermediate checkin: Had to resolve some build errors. Working on two
135 * docked ships moving as one.
146 #define PF_ACCELERATES (1 << 1)
147 #define PF_USE_VEL (1 << 2) // Use velocity present in physics_info struct, don't call physics_sim_vel.
148 #define PF_AFTERBURNER_ON (1 << 3) // Afterburner currently engaged.
149 #define PF_SLIDE_ENABLED (1 << 4) // Allow descent style sliding
150 #define PF_REDUCED_DAMP (1 << 5) // Allows reduced damping on z (for death, shockwave) (CAN be reset in physics)
151 #define PF_IN_SHOCKWAVE (1 << 6) // Indicates whether object has recently been hit by shockwave (used to enable shake)
152 #define PF_DEAD_DAMP (1 << 7) // Makes forward damping same as sideways (NOT reset in physics)
153 #define PF_AFTERBURNER_WAIT (1 << 8) // true when afterburner cannot be used. replaces variable used in afterburner code
154 #define PF_CONST_VEL (1 << 9) // Use velocity in phys_info struct. Optimize weapons in phys_sim
155 #define PF_WARP_IN (1 << 10) // Use when ship is warping in
156 #define PF_SPECIAL_WARP_IN (1 << 11) // Use when ship is warping in and we want to slow the ship faster than normal game physics
157 #define PF_WARP_OUT (1 << 12) // Use when ship is warping out
158 #define PF_SPECIAL_WARP_OUT (1 << 13) // Use when ship is warping out and we want to slow the ship faster than normal game physics
160 //information for physics sim for an object
161 typedef struct physics_info {
162 uint flags; //misc physics flags
164 float mass; //the mass of this object
166 matrix I_body_inv; // inverse moment of inertia tensor (used to calculate rotational effects)
168 float rotdamp; //rotational velocity damping
169 float side_slip_time_const; // time const for achieving desired velocity in the local sideways direction
170 // value should be zero for no sideslip and increase depending on desired slip
172 vector max_vel; //maximum foward velocity in x,y,z
173 vector afterburner_max_vel; // maximum foward velocity in x,y,z while afterburner engaged
174 vector max_rotvel; //maximum p,b,h rotational velocity
175 float max_rear_vel; //maximum velocity in the backwards Z direction
177 // Acceleration rates. Only used if flag PF_ACCELERATES is set
178 // starting from rest time to reach .50 v_max 0.69 time const
179 // time to reach .75 v_max 1.39 time const
181 float forward_accel_time_const; // forward acceleration time const
182 float afterburner_forward_accel_time_const; // forward acceleration time const while afterburner engaged
183 float forward_decel_time_const; // forward deceleration time const
184 float slide_accel_time_const; // slide acceleration time const
185 float slide_decel_time_const; // slide deceleration time const
186 float shockwave_shake_amp; // amplitude of shockwave shake at onset
188 // These get changed by the control code. The physics uses these
189 // as input values when doing physics.
190 vector prev_ramp_vel; // follows the user's desired velocity
191 vector desired_vel; // in world coord
192 vector desired_rotvel; // in local coord
193 float forward_thrust; // How much the forward thruster is applied. 0-1.
195 // Data that changes each frame. Physics fills these in each frame.
196 vector vel; // The current velocity vector of this object
197 vector rotvel; // The current rotational velecity (angles)
198 float speed; // Yes, this can be derived from velocity, but that's expensive!
199 float fspeed; // Speed in the forward direction.
201 vector prev_fvec; // Used in AI for momentum.
202 matrix last_rotmat; // Used for moving two objects together and for editor.
204 int afterburner_decay; // timestamp used to control how long ship shakes after afterburner released
205 int shockwave_decay; // timestamp used to control how long ship affected after hit by shockwave
206 int reduced_damp_decay; // timestamp used to control how long ship ship has reduced damp physics
209 // All of these are numbers from -1.0 to 1.0 indicating
210 // what percent of full velocity you want to go.
211 typedef struct control_info {
212 float pitch; // -1.0 to 1.0
218 float forward_cruise_percent; // percentage used for forward cruising
219 // This is a special case from -100 to 100
221 // below is information that are used by the player controls for firing information.
222 int fire_primary_count;
223 int fire_secondary_count;
224 int fire_countermeasure_count;
225 int fire_debug_count; // should this be around an NDEBUG #if/#endif?
227 // afterburner control information
228 int afterburner_start;
229 int afterburner_stop;
233 extern int physics_paused; // Set means don't do physics, except for player.
235 // To use the "Descent-ship" physics:
236 // controls_read_all(&ci, FrameSecs );
237 // physics_read_flying_controls( &ViewerOrient, &ViewerPhysics, FrameSecs, &ci );
238 // physics_sim(&ViewerPos, &ViewerOrient, &ViewerPhysics, FrameSecs );
239 extern void physics_init( physics_info * pi );
240 extern void physics_read_flying_controls( matrix * orient, physics_info * pi, control_info * ci, float sim_time, vector *wash_rot=NULL);
241 extern void physics_sim(vector *position, matrix * orient, physics_info * pi, float sim_time );
242 extern void physics_sim_editor(vector *position, matrix * orient, physics_info * pi, float sim_time);
244 extern void physics_sim_vel(vector * position, physics_info * pi, float sim_time, matrix * orient);
245 extern void physics_sim_rot(matrix * orient, physics_info * pi, float sim_time );
246 extern void physics_apply_whack(vector *force, vector *pos, physics_info *pi, matrix *orient, float mass);
247 extern void physics_apply_shock(vector *direction_vec, float pressure, physics_info *pi, matrix *orient, vector *min, vector *max, float radius);
248 extern void physics_collide_whack(vector *impulse, vector *delta_rotvel, physics_info *pi, matrix *orient);
249 int check_rotvel_limit( physics_info *pi );
253 // functions which use physics calcs to predict position and velocity
254 void physics_predict_pos(physics_info *pi, float delta_time, vector *predicted_pos);
255 void physics_predict_vel(physics_info *pi, float delta_time, vector *predicted_vel);
256 void physics_predict_pos_and_vel(physics_info *pi, float delta_time, vector *predicted_vel, vector *predicted_pos);
258 // If physics_set_viewer is called with the viewer's physics_info, then
259 // this variable tracks the viewer's bank. This is used for g3_draw_rotated_bitmap.
260 extern float Physics_viewer_bank;
262 // If you would like Physics_viewer_bank to be tracked (Which is needed
263 // for rotating 3d bitmaps) call this and pass it a pointer to the
264 // viewer's physics info.
265 #define PHYSICS_VIEWER_FRONT 0
266 #define PHYSICS_VIEWER_LEFT 1
267 #define PHYSICS_VIEWER_RIGHT 2
268 #define PHYSICS_VIEWER_REAR 3
269 #define PHYSICS_VIEWER_UP 4
270 void physics_set_viewer( physics_info * p, int dir );