simplified explosion rendering a little (probably a very minor slowdown, but more...
[divverent/darkplaces.git] / 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 explosiontexcoord2f[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_LoadTexture2D(explosiontexturepool, "explosiontexture", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE, NULL);
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_LoadTexture2D(explosiontexturepool, "explosiontexturefog", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE, NULL);
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 = ((double) row / EXPLOSIONGRID) * M_PI * 2;
107         b = (((double) column / EXPLOSIONGRID) + 0.5) * M_PI;
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         explosiontexcoord2f[i][0] = (float) column / (float) EXPLOSIONGRID;
116         explosiontexcoord2f[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_DrawExplosionCallback(const void *calldata1, int calldata2)
177 {
178         int i, numtriangles, numverts;
179         float *c, diff[3], centerdir[3], alpha, dist;
180         rmeshstate_t m;
181         const explosion_t *e;
182         e = calldata1;
183
184         memset(&m, 0, sizeof(m));
185         m.blendfunc1 = GL_SRC_ALPHA;
186         m.blendfunc2 = GL_ONE;
187         m.tex[0] = R_GetTexture(explosiontexture);
188         R_Mesh_Matrix(&r_identitymatrix);
189         R_Mesh_State(&m);
190
191         numtriangles = EXPLOSIONTRIS;
192         numverts = EXPLOSIONVERTS;
193         GL_UseColorArray();
194         R_Mesh_GetSpace(numverts);
195
196         R_Mesh_CopyVertex3f(e->vert[0], numverts);
197         R_Mesh_CopyTexCoord2f(0, explosiontexcoord2f[0], numverts);
198         alpha = e->alpha * r_colorscale;
199         VectorSubtract(r_origin, e->origin, centerdir);
200         VectorNormalizeFast(centerdir);
201         for (i = 0, c = varray_color4f;i < EXPLOSIONVERTS;i++, c += 4)
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                         if (fogenabled)
209                         {
210                                 // use inverse fog alpha
211                                 VectorSubtract(e->vert[i], r_origin, diff);
212                                 dist *= (1 - exp(fogdensity/DotProduct(diff,diff)));
213                         }
214                 }
215                 else
216                         dist = 0;
217                 c[0] = c[1] = c[2] = dist;
218                 c[3] = 1;
219         }
220         R_Mesh_Draw(numverts, numtriangles, explosiontris[0]);
221 }
222
223 void R_MoveExplosion(explosion_t *e)
224 {
225         int i;
226         float dot, frictionscale, end[3], impact[3], normal[3], frametime;
227
228         frametime = cl.time - e->time;
229         e->time = cl.time;
230         e->alpha = EXPLOSIONFADESTART - (cl.time - e->starttime) * EXPLOSIONFADERATE;
231         if (e->alpha <= 0.01f)
232         {
233                 e->alpha = -1;
234                 return;
235         }
236         frictionscale = 1 - frametime;
237         frictionscale = bound(0, frictionscale, 1);
238         for (i = 0;i < EXPLOSIONVERTS;i++)
239         {
240                 if (e->vertvel[i][0] || e->vertvel[i][1] || e->vertvel[i][2])
241                 {
242                         VectorScale(e->vertvel[i], frictionscale, e->vertvel[i]);
243                         VectorMA(e->vert[i], frametime, e->vertvel[i], end);
244                         if (r_explosionclip.integer)
245                         {
246                                 if (CL_TraceLine(e->vert[i], end, impact, normal, 0, true, NULL) < 1)
247                                 {
248                                         // clip velocity against the wall
249                                         dot = DotProduct(e->vertvel[i], normal) * -1.125f;
250                                         VectorMA(e->vertvel[i], dot, normal, e->vertvel[i]);
251                                 }
252                                 VectorCopy(impact, e->vert[i]);
253                         }
254                         else
255                                 VectorCopy(end, e->vert[i]);
256                 }
257         }
258         for (i = 0;i < EXPLOSIONGRID;i++)
259                 VectorCopy(e->vert[i * (EXPLOSIONGRID + 1)], e->vert[i * (EXPLOSIONGRID + 1) + EXPLOSIONGRID]);
260         memcpy(e->vert[EXPLOSIONGRID * (EXPLOSIONGRID + 1)], e->vert[0], sizeof(float[3]) * (EXPLOSIONGRID + 1));
261 }
262
263
264 void R_MoveExplosions(void)
265 {
266         int i;
267         float frametime;
268
269         frametime = cl.time - cl.oldtime;
270
271         for (i = 0;i < MAX_EXPLOSIONS;i++)
272                 if (explosion[i].alpha > 0.01f)
273                         R_MoveExplosion(&explosion[i]);
274 }
275
276 void R_DrawExplosions(void)
277 {
278         int i;
279
280         if (!r_drawexplosions.integer)
281                 return;
282         for (i = 0;i < MAX_EXPLOSIONS;i++)
283                 if (explosion[i].alpha > 0.01f)
284                         R_MeshQueue_AddTransparent(explosion[i].origin, R_DrawExplosionCallback, &explosion[i], 0);
285 }
286