r_explosion.c

   1 /*
   2 Copyright (C) 1996-1997 Id Software, Inc.
   3
   4 This program is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU General Public License
   6 as published by the Free Software Foundation; either version 2
   7 of the License, or (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  12
  13 See the GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19 */
  20
  21 #include "quakedef.h"
  22 #include "cl_collision.h"
  23
  24 #define MAX_EXPLOSIONS 64
  25 #define EXPLOSIONGRID 8
  26 #define EXPLOSIONVERTS ((EXPLOSIONGRID+1)*(EXPLOSIONGRID+1))
  27 #define EXPLOSIONTRIS (EXPLOSIONGRID*EXPLOSIONGRID*2)
  28 #define EXPLOSIONSTARTVELOCITY (256.0f)
  29 #define EXPLOSIONFADESTART (1.5f)
  30 #define EXPLOSIONFADERATE (3.0f)
  31
  32 float explosiontexcoords[EXPLOSIONVERTS][2];
  33 int explosiontris[EXPLOSIONTRIS][3];
  34 int explosionnoiseindex[EXPLOSIONVERTS];
  35 vec3_t explosionpoint[EXPLOSIONVERTS];
  36 vec3_t explosionspherevertvel[EXPLOSIONVERTS];
  37
  38 typedef struct explosion_s
  39 {
  40         float starttime;
  41         float time;
  42         float alpha;
  43         vec3_t origin;
  44         vec3_t vert[EXPLOSIONVERTS];
  45         vec3_t vertvel[EXPLOSIONVERTS];
  46 }
  47 explosion_t;
  48
  49 explosion_t explosion[MAX_EXPLOSIONS];
  50
  51 rtexture_t      *explosiontexture;
  52 rtexture_t      *explosiontexturefog;
  53
  54 rtexturepool_t  *explosiontexturepool;
  55
  56 cvar_t r_explosionclip = {CVAR_SAVE, "r_explosionclip", "1"};
  57 cvar_t r_drawexplosions = {0, "r_drawexplosions", "1"};
  58
  59 void r_explosion_start(void)
  60 {
  61         int x, y;
  62         qbyte noise1[128][128], noise2[128][128], noise3[128][128], data[128][128][4];
  63         explosiontexturepool = R_AllocTexturePool();
  64         fractalnoise(&noise1[0][0], 128, 32);
  65         fractalnoise(&noise2[0][0], 128, 4);
  66         fractalnoise(&noise3[0][0], 128, 4);
  67         for (y = 0;y < 128;y++)
  68         {
  69                 for (x = 0;x < 128;x++)
  70                 {
  71                         int j, r, g, b, a;
  72                         j = (noise1[y][x] * noise2[y][x]) * 3 / 256 - 128;
  73                         r = (j * 512) / 256;
  74                         g = (j * 256) / 256;
  75                         b = (j * 128) / 256;
  76                         a = noise3[y][x] * 3 - 128;
  77                         data[y][x][0] = bound(0, r, 255);
  78                         data[y][x][1] = bound(0, g, 255);
  79                         data[y][x][2] = bound(0, b, 255);
  80                         data[y][x][3] = bound(0, a, 255);
  81                 }
  82         }
  83         explosiontexture = R_LoadTexture (explosiontexturepool, "explosiontexture", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE);
  84         for (y = 0;y < 128;y++)
  85                 for (x = 0;x < 128;x++)
  86                         data[y][x][0] = data[y][x][1] = data[y][x][2] = 255;
  87         explosiontexturefog = R_LoadTexture (explosiontexturepool, "explosiontexturefog", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE);
  88         // note that explosions survive the restart
  89 }
  90
  91 void r_explosion_shutdown(void)
  92 {
  93         R_FreeTexturePool(&explosiontexturepool);
  94 }
  95
  96 void r_explosion_newmap(void)
  97 {
  98         memset(explosion, 0, sizeof(explosion));
  99 }
 100
 101 int R_ExplosionVert(int column, int row)
 102 {
 103         int i;
 104         float a, b, c;
 105         i = row * (EXPLOSIONGRID + 1) + column;
 106         a = row * M_PI * 2 / EXPLOSIONGRID;
 107         b = column * M_PI * 2 / EXPLOSIONGRID;
 108         c = cos(b);
 109         explosionpoint[i][0] = cos(a) * c;
 110         explosionpoint[i][1] = sin(a) * c;
 111         explosionpoint[i][2] = -sin(b);
 112         explosionspherevertvel[i][0] = explosionpoint[i][0] * EXPLOSIONSTARTVELOCITY;
 113         explosionspherevertvel[i][1] = explosionpoint[i][1] * EXPLOSIONSTARTVELOCITY;
 114         explosionspherevertvel[i][2] = explosionpoint[i][2] * EXPLOSIONSTARTVELOCITY;
 115         explosiontexcoords[i][0] = (float) column / (float) EXPLOSIONGRID;
 116         explosiontexcoords[i][1] = (float) row / (float) EXPLOSIONGRID;
 117         // top and bottom rows are all one position...
 118         if (row == 0 || row == EXPLOSIONGRID)
 119                 column = 0;
 120         explosionnoiseindex[i] = (row % EXPLOSIONGRID) * EXPLOSIONGRID + (column % EXPLOSIONGRID);
 121         return i;
 122 }
 123
 124 void R_Explosion_Init(void)
 125 {
 126         int i, x, y;
 127         i = 0;
 128         for (y = 0;y < EXPLOSIONGRID;y++)
 129         {
 130                 for (x = 0;x < EXPLOSIONGRID;x++)
 131                 {
 132                         explosiontris[i][0] = R_ExplosionVert(x    , y    );
 133                         explosiontris[i][1] = R_ExplosionVert(x + 1, y    );
 134                         explosiontris[i][2] = R_ExplosionVert(x    , y + 1);
 135                         i++;
 136                         explosiontris[i][0] = R_ExplosionVert(x + 1, y    );
 137                         explosiontris[i][1] = R_ExplosionVert(x + 1, y + 1);
 138                         explosiontris[i][2] = R_ExplosionVert(x    , y + 1);
 139                         i++;
 140                 }
 141         }
 142
 143         Cvar_RegisterVariable(&r_explosionclip);
 144         Cvar_RegisterVariable(&r_drawexplosions);
 145
 146         R_RegisterModule("R_Explosions", r_explosion_start, r_explosion_shutdown, r_explosion_newmap);
 147 }
 148
 149 void R_NewExplosion(vec3_t org)
 150 {
 151         int i, j;
 152         float dist;
 153         qbyte noise[EXPLOSIONGRID*EXPLOSIONGRID];
 154         fractalnoisequick(noise, EXPLOSIONGRID, 4); // adjust noise grid size according to explosion
 155         for (i = 0;i < MAX_EXPLOSIONS;i++)
 156         {
 157                 if (explosion[i].alpha <= 0.01f)
 158                 {
 159                         explosion[i].starttime = cl.time;
 160                         explosion[i].time = explosion[i].starttime - 0.1;
 161                         explosion[i].alpha = EXPLOSIONFADESTART;
 162                         VectorCopy(org, explosion[i].origin);
 163                         for (j = 0;j < EXPLOSIONVERTS;j++)
 164                         {
 165                                 // calculate start
 166                                 VectorCopy(explosion[i].origin, explosion[i].vert[j]);
 167                                 // calculate velocity
 168                                 dist = noise[explosionnoiseindex[j]] * (1.0f / 255.0f) + 0.5;
 169                                 VectorScale(explosionspherevertvel[j], dist, explosion[i].vertvel[j]);
 170                         }
 171                         break;
 172                 }
 173         }
 174 }
 175
 176 void R_DrawExplosion(explosion_t *e)
 177 {
 178         int i;
 179         float c[EXPLOSIONVERTS][4], diff[3], centerdir[3], ifog, alpha, dist;
 180         rmeshinfo_t m;
 181         memset(&m, 0, sizeof(m));
 182         m.transparent = true;
 183         m.blendfunc1 = GL_SRC_ALPHA;
 184         m.blendfunc2 = GL_ONE;
 185         m.numtriangles = EXPLOSIONTRIS;
 186         m.index = &explosiontris[0][0];
 187         m.numverts = EXPLOSIONVERTS;
 188         m.vertex = &e->vert[0][0];
 189         m.vertexstep = sizeof(float[3]);
 190         alpha = e->alpha;
 191         m.cr = 1;
 192         m.cg = 1;
 193         m.cb = 1;
 194         m.ca = 1; //alpha;
 195         m.color = &c[0][0];
 196         m.colorstep = sizeof(float[4]);
 197         VectorSubtract(r_origin, e->origin, centerdir);
 198         VectorNormalizeFast(centerdir);
 199         if (fogenabled)
 200         {
 201                 for (i = 0;i < EXPLOSIONVERTS;i++)
 202                 {
 203                         VectorSubtract(e->vert[i], e->origin, diff);
 204                         VectorNormalizeFast(diff);
 205                         dist = (DotProduct(diff, centerdir) * 6.0f - 4.0f) * alpha;
 206                         if (dist > 0)
 207                         {
 208                                 // use inverse fog alpha
 209                                 VectorSubtract(e->vert[i], r_origin, diff);
 210                                 ifog = 1 - exp(fogdensity/DotProduct(diff,diff));
 211                                 dist = dist * ifog;
 212                                 if (dist < 0)
 213                                         dist = 0;
 214                         }
 215                         else
 216                                 dist = 0;
 217                         c[i][0] = c[i][1] = c[i][2] = dist;
 218                         c[i][3] = 1;
 219                 }
 220         }
 221         else
 222         {
 223                 for (i = 0;i < EXPLOSIONVERTS;i++)
 224                 {
 225                         VectorSubtract(e->vert[i], e->origin, diff);
 226                         VectorNormalizeFast(diff);
 227                         dist = (DotProduct(diff, centerdir) * 6.0f - 4.0f) * alpha;
 228                         if (dist < 0)
 229                                 dist = 0;
 230                         c[i][0] = c[i][1] = c[i][2] = dist;
 231                         c[i][3] = 1;
 232                 }
 233         }
 234         m.tex[0] = R_GetTexture(explosiontexture);
 235         m.texcoords[0] = &explosiontexcoords[0][0];
 236         m.texcoordstep[0] = sizeof(float[2]);
 237
 238         R_Mesh_Draw(&m);
 239 }
 240
 241 void R_MoveExplosion(explosion_t *e)
 242 {
 243         int i;
 244         float dot, frictionscale, end[3], impact[3], normal[3], frametime;
 245
 246         frametime = cl.time - e->time;
 247         e->time = cl.time;
 248         e->alpha = EXPLOSIONFADESTART - (cl.time - e->starttime) * EXPLOSIONFADERATE;
 249         if (e->alpha <= 0.01f)
 250         {
 251                 e->alpha = -1;
 252                 return;
 253         }
 254         frictionscale = 1 - frametime;
 255         frictionscale = bound(0, frictionscale, 1);
 256         for (i = 0;i < EXPLOSIONVERTS;i++)
 257         {
 258                 if (e->vertvel[i][0] || e->vertvel[i][1] || e->vertvel[i][2])
 259                 {
 260                         VectorScale(e->vertvel[i], frictionscale, e->vertvel[i]);
 261                         VectorMA(e->vert[i], frametime, e->vertvel[i], end);
 262                         if (r_explosionclip.integer)
 263                         {
 264                                 if (CL_TraceLine(e->vert[i], end, impact, normal, 0, true) < 1)
 265                                 {
 266                                         // clip velocity against the wall
 267                                         dot = DotProduct(e->vertvel[i], normal) * -1.125f;
 268                                         VectorMA(e->vertvel[i], dot, normal, e->vertvel[i]);
 269                                 }
 270                                 VectorCopy(impact, e->vert[i]);
 271                         }
 272                         else
 273                                 VectorCopy(end, e->vert[i]);
 274                 }
 275         }
 276         for (i = 0;i < EXPLOSIONGRID;i++)
 277                 VectorCopy(e->vert[i * (EXPLOSIONGRID + 1)], e->vert[i * (EXPLOSIONGRID + 1) + EXPLOSIONGRID]);
 278         memcpy(e->vert[EXPLOSIONGRID * (EXPLOSIONGRID + 1)], e->vert[0], sizeof(float[3]) * (EXPLOSIONGRID + 1));
 279 }
 280
 281
 282 void R_MoveExplosions(void)
 283 {
 284         int i;
 285         float frametime;
 286
 287         frametime = cl.time - cl.oldtime;
 288
 289         for (i = 0;i < MAX_EXPLOSIONS;i++)
 290                 if (explosion[i].alpha > 0.01f)
 291                         R_MoveExplosion(&explosion[i]);
 292 }
 293
 294 void R_DrawExplosions(void)
 295 {
 296         int i;
 297
 298         if (!r_drawexplosions.integer)
 299                 return;
 300         for (i = 0;i < MAX_EXPLOSIONS;i++)
 301                 if (explosion[i].alpha > 0.01f)
 302                         R_DrawExplosion(&explosion[i]);
 303 }
 304