Tomaz patch to implement controllable fade rate in explosions
[xonotic/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
30 float explosiontexcoord2f[EXPLOSIONVERTS][2];
31 int explosiontris[EXPLOSIONTRIS][3];
32 int explosionnoiseindex[EXPLOSIONVERTS];
33 vec3_t explosionpoint[EXPLOSIONVERTS];
34 vec3_t explosionspherevertvel[EXPLOSIONVERTS];
35
36 typedef struct explosion_s
37 {
38         float starttime;
39         float time;
40         float alpha;
41         float fade;
42         vec3_t origin;
43         vec3_t vert[EXPLOSIONVERTS];
44         vec3_t vertvel[EXPLOSIONVERTS];
45 }
46 explosion_t;
47
48 explosion_t explosion[MAX_EXPLOSIONS];
49
50 rtexture_t      *explosiontexture;
51 rtexture_t      *explosiontexturefog;
52
53 rtexturepool_t  *explosiontexturepool;
54
55 cvar_t r_explosionclip = {CVAR_SAVE, "r_explosionclip", "1"};
56 cvar_t r_drawexplosions = {0, "r_drawexplosions", "1"};
57
58 void r_explosion_start(void)
59 {
60         int x, y;
61         qbyte noise1[128][128], noise2[128][128], noise3[128][128], data[128][128][4];
62         explosiontexturepool = R_AllocTexturePool();
63         fractalnoise(&noise1[0][0], 128, 32);
64         fractalnoise(&noise2[0][0], 128, 4);
65         fractalnoise(&noise3[0][0], 128, 4);
66         for (y = 0;y < 128;y++)
67         {
68                 for (x = 0;x < 128;x++)
69                 {
70                         int j, r, g, b, a;
71                         j = (noise1[y][x] * noise2[y][x]) * 3 / 256 - 128;
72                         r = (j * 512) / 256;
73                         g = (j * 256) / 256;
74                         b = (j * 128) / 256;
75                         a = noise3[y][x] * 3 - 128;
76                         data[y][x][0] = bound(0, r, 255);
77                         data[y][x][1] = bound(0, g, 255);
78                         data[y][x][2] = bound(0, b, 255);
79                         data[y][x][3] = bound(0, a, 255);
80                 }
81         }
82         explosiontexture = R_LoadTexture2D(explosiontexturepool, "explosiontexture", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE, NULL);
83         for (y = 0;y < 128;y++)
84                 for (x = 0;x < 128;x++)
85                         data[y][x][0] = data[y][x][1] = data[y][x][2] = 255;
86         explosiontexturefog = R_LoadTexture2D(explosiontexturepool, "explosiontexturefog", 128, 128, &data[0][0][0], TEXTYPE_RGBA, TEXF_MIPMAP | TEXF_ALPHA | TEXF_PRECACHE, NULL);
87         // note that explosions survive the restart
88 }
89
90 void r_explosion_shutdown(void)
91 {
92         R_FreeTexturePool(&explosiontexturepool);
93 }
94
95 void r_explosion_newmap(void)
96 {
97         memset(explosion, 0, sizeof(explosion));
98 }
99
100 int R_ExplosionVert(int column, int row)
101 {
102         int i;
103         float yaw, pitch;
104         // top and bottom rows are all one position...
105         if (row == 0 || row == EXPLOSIONGRID)
106                 column = 0;
107         i = row * (EXPLOSIONGRID + 1) + column;
108         yaw = ((double) column / EXPLOSIONGRID) * M_PI * 2;
109         pitch = (((double) row / EXPLOSIONGRID) - 0.5) * M_PI;
110         explosionpoint[i][0] = cos(yaw) *  cos(pitch);
111         explosionpoint[i][1] = sin(yaw) *  cos(pitch);
112         explosionpoint[i][2] =        1 * -sin(pitch);
113         explosionspherevertvel[i][0] = explosionpoint[i][0] * EXPLOSIONSTARTVELOCITY;
114         explosionspherevertvel[i][1] = explosionpoint[i][1] * EXPLOSIONSTARTVELOCITY;
115         explosionspherevertvel[i][2] = explosionpoint[i][2] * EXPLOSIONSTARTVELOCITY;
116         explosiontexcoord2f[i][0] = (float) column / (float) EXPLOSIONGRID;
117         explosiontexcoord2f[i][1] = (float) row / (float) EXPLOSIONGRID;
118         explosionnoiseindex[i] = (row % EXPLOSIONGRID) * EXPLOSIONGRID + (column % EXPLOSIONGRID);
119         return i;
120 }
121
122 void R_Explosion_Init(void)
123 {
124         int i, x, y;
125         i = 0;
126         for (y = 0;y < EXPLOSIONGRID;y++)
127         {
128                 for (x = 0;x < EXPLOSIONGRID;x++)
129                 {
130                         explosiontris[i][0] = R_ExplosionVert(x    , y    );
131                         explosiontris[i][1] = R_ExplosionVert(x + 1, y    );
132                         explosiontris[i][2] = R_ExplosionVert(x    , y + 1);
133                         i++;
134                         explosiontris[i][0] = R_ExplosionVert(x + 1, y    );
135                         explosiontris[i][1] = R_ExplosionVert(x + 1, y + 1);
136                         explosiontris[i][2] = R_ExplosionVert(x    , y + 1);
137                         i++;
138                 }
139         }
140
141         Cvar_RegisterVariable(&r_explosionclip);
142         Cvar_RegisterVariable(&r_drawexplosions);
143
144         R_RegisterModule("R_Explosions", r_explosion_start, r_explosion_shutdown, r_explosion_newmap);
145 }
146
147 void R_NewExplosion(vec3_t org)
148 {
149         int i, j;
150         float dist;
151         qbyte noise[EXPLOSIONGRID*EXPLOSIONGRID];
152         fractalnoisequick(noise, EXPLOSIONGRID, 4); // adjust noise grid size according to explosion
153         for (i = 0;i < MAX_EXPLOSIONS;i++)
154         {
155                 if (explosion[i].alpha <= cl_explosions_alpha_end.value)
156                 {
157                         explosion[i].starttime = cl.time;
158                         explosion[i].time = explosion[i].starttime - 0.1;
159                         explosion[i].alpha = cl_explosions_alpha_start.value;
160                         explosion[i].fade = (cl_explosions_alpha_start.value - cl_explosions_alpha_end.value) / cl_explosions_lifetime.value;
161                         VectorCopy(org, explosion[i].origin);
162                         for (j = 0;j < EXPLOSIONVERTS;j++)
163                         {
164                                 // calculate start
165                                 VectorCopy(explosion[i].origin, explosion[i].vert[j]);
166                                 // calculate velocity
167                                 dist = noise[explosionnoiseindex[j]] * (1.0f / 255.0f) + 0.5;
168                                 VectorScale(explosionspherevertvel[j], dist, explosion[i].vertvel[j]);
169                         }
170                         break;
171                 }
172         }
173 }
174
175 void R_DrawExplosionCallback(const void *calldata1, int calldata2)
176 {
177         int numtriangles, numverts;
178         float alpha;
179         rmeshstate_t m;
180         const explosion_t *e;
181         e = calldata1;
182
183         GL_BlendFunc(GL_SRC_ALPHA, GL_ONE);
184         GL_DepthMask(false);
185         GL_DepthTest(true);
186         R_Mesh_Matrix(&r_identitymatrix);
187
188         numtriangles = EXPLOSIONTRIS;
189         numverts = EXPLOSIONVERTS;
190         alpha = e->alpha;
191
192         memset(&m, 0, sizeof(m));
193         m.tex[0] = R_GetTexture(explosiontexture);
194         m.pointer_texcoord[0] = explosiontexcoord2f[0];
195         m.pointer_vertex = e->vert[0];
196         R_Mesh_State(&m);
197
198         GL_Color(alpha, alpha, alpha, 1);
199
200         GL_LockArrays(0, numverts);
201         R_Mesh_Draw(numverts, numtriangles, explosiontris[0]);
202         GL_LockArrays(0, 0);
203 }
204
205 void R_MoveExplosion(explosion_t *e)
206 {
207         int i;
208         float dot, frictionscale, end[3], impact[3], normal[3], frametime;
209
210         frametime = cl.time - e->time;
211         e->time = cl.time;
212         e->alpha = e->alpha - (e->fade * frametime);
213         if (e->alpha <= cl_explosions_alpha_end.value)
214         {
215                 e->alpha = -1;
216                 return;
217         }
218         frictionscale = 1 - frametime;
219         frictionscale = bound(0, frictionscale, 1);
220         for (i = 0;i < EXPLOSIONVERTS;i++)
221         {
222                 if (e->vertvel[i][0] || e->vertvel[i][1] || e->vertvel[i][2])
223                 {
224                         VectorScale(e->vertvel[i], frictionscale, e->vertvel[i]);
225                         VectorMA(e->vert[i], frametime, e->vertvel[i], end);
226                         if (r_explosionclip.integer)
227                         {
228                                 if (CL_TraceLine(e->vert[i], end, impact, normal, true, NULL, SUPERCONTENTS_SOLID) < 1)
229                                 {
230                                         // clip velocity against the wall
231                                         dot = DotProduct(e->vertvel[i], normal) * -1.125f;
232                                         VectorMA(e->vertvel[i], dot, normal, e->vertvel[i]);
233                                 }
234                                 VectorCopy(impact, e->vert[i]);
235                         }
236                         else
237                                 VectorCopy(end, e->vert[i]);
238                 }
239         }
240 }
241
242
243 void R_MoveExplosions(void)
244 {
245         int i;
246         float frametime;
247
248         frametime = cl.time - cl.oldtime;
249
250         for (i = 0;i < MAX_EXPLOSIONS;i++)
251                 if (explosion[i].alpha > cl_explosions_alpha_end.value)
252                         R_MoveExplosion(&explosion[i]);
253 }
254
255 void R_DrawExplosions(void)
256 {
257         int i;
258
259         if (!r_drawexplosions.integer)
260                 return;
261         for (i = 0;i < MAX_EXPLOSIONS;i++)
262                 if (explosion[i].alpha > cl_explosions_alpha_end.value)
263                         R_MeshQueue_AddTransparent(explosion[i].origin, R_DrawExplosionCallback, &explosion[i], 0);
264 }
265