sv_light.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 // r_light.c
  21
  22 #include "quakedef.h"
  23
  24 int SV_RecursiveLightPoint (vec3_t color, mnode_t *node, float x, float y, float startz, float endz)
  25 {
  26         int             side, distz = endz - startz;
  27         float   front, back;
  28         float   mid;
  29
  30 loc0:
  31         if (node->contents < 0)
  32                 return false;           // didn't hit anything
  33
  34         switch (node->plane->type)
  35         {
  36         case PLANE_X:
  37                 node = node->children[x < node->plane->dist];
  38                 goto loc0;
  39         case PLANE_Y:
  40                 node = node->children[y < node->plane->dist];
  41                 goto loc0;
  42         case PLANE_Z:
  43                 side = startz < node->plane->dist;
  44                 if ((endz < node->plane->dist) == side)
  45                 {
  46                         node = node->children[side];
  47                         goto loc0;
  48                 }
  49                 // found an intersection
  50 //              mid = startz + (endz - startz) * (startz - node->plane->dist) / (startz - endz);
  51 //              mid = startz + distz * (startz - node->plane->dist) / (-distz);
  52 //              mid = startz + (-(startz - node->plane->dist));
  53 //              mid = startz - (startz - node->plane->dist);
  54 //              mid = startz + node->plane->dist - startz;
  55                 mid = node->plane->dist;
  56                 break;
  57         default:
  58                 back = front = x * node->plane->normal[0] + y * node->plane->normal[1];
  59                 front += startz * node->plane->normal[2];
  60                 back += endz * node->plane->normal[2];
  61                 side = front < node->plane->dist;
  62                 if ((back < node->plane->dist) == side)
  63                 {
  64                         node = node->children[side];
  65                         goto loc0;
  66                 }
  67                 // found an intersection
  68 //              mid = startz + (endz - startz) * ((front - node->plane->dist) / ((front - node->plane->dist) - (back - node->plane->dist)));
  69 //              mid = startz + (endz - startz) * ((front - node->plane->dist) / (front - back));
  70                 mid = startz + distz * (front - node->plane->dist) / (front - back);
  71                 break;
  72         }
  73
  74         // go down front side
  75         if (node->children[side]->contents >= 0 && SV_RecursiveLightPoint (color, node->children[side], x, y, startz, mid))
  76                 return true;    // hit something
  77         else
  78         {
  79                 // check for impact on this node
  80                 if (node->numsurfaces)
  81                 {
  82                         int i, ds, dt;
  83                         msurface_t *surf;
  84
  85                         surf = sv.worldmodel->surfaces + node->firstsurface;
  86                         for (i = 0;i < node->numsurfaces;i++, surf++)
  87                         {
  88                                 if (!(surf->flags & SURF_LIGHTMAP))
  89                                         continue;
  90
  91                                 ds = (int) (x * surf->texinfo->vecs[0][0] + y * surf->texinfo->vecs[0][1] + mid * surf->texinfo->vecs[0][2] + surf->texinfo->vecs[0][3]);
  92                                 dt = (int) (x * surf->texinfo->vecs[1][0] + y * surf->texinfo->vecs[1][1] + mid * surf->texinfo->vecs[1][2] + surf->texinfo->vecs[1][3]);
  93
  94                                 if (ds < surf->texturemins[0] || dt < surf->texturemins[1])
  95                                         continue;
  96
  97                                 ds -= surf->texturemins[0];
  98                                 dt -= surf->texturemins[1];
  99
 100                                 if (ds > surf->extents[0] || dt > surf->extents[1])
 101                                         continue;
 102
 103                                 if (surf->samples)
 104                                 {
 105                                         qbyte *lightmap;
 106                                         int maps, line3, size3, dsfrac = ds & 15, dtfrac = dt & 15, scale = 0, r00 = 0, g00 = 0, b00 = 0, r01 = 0, g01 = 0, b01 = 0, r10 = 0, g10 = 0, b10 = 0, r11 = 0, g11 = 0, b11 = 0;
 107                                         line3 = ((surf->extents[0]>>4)+1)*3;
 108                                         size3 = ((surf->extents[0]>>4)+1) * ((surf->extents[1]>>4)+1)*3; // LordHavoc: *3 for colored lighting
 109
 110                                         lightmap = surf->samples + ((dt>>4) * ((surf->extents[0]>>4)+1) + (ds>>4))*3; // LordHavoc: *3 for color
 111
 112                                         for (maps = 0;maps < MAXLIGHTMAPS && surf->styles[maps] != 255;maps++)
 113                                         {
 114                                                 scale = 256; // FIXME: server doesn't know what light styles are doing
 115                                                 r00 += lightmap[      0] * scale;g00 += lightmap[      1] * scale;b00 += lightmap[      2] * scale;
 116                                                 r01 += lightmap[      3] * scale;g01 += lightmap[      4] * scale;b01 += lightmap[      5] * scale;
 117                                                 r10 += lightmap[line3+0] * scale;g10 += lightmap[line3+1] * scale;b10 += lightmap[line3+2] * scale;
 118                                                 r11 += lightmap[line3+3] * scale;g11 += lightmap[line3+4] * scale;b11 += lightmap[line3+5] * scale;
 119                                                 lightmap += size3;
 120                                         }
 121
 122                                         color[0] += (float) ((((((((r11-r10) * dsfrac) >> 4) + r10)-((((r01-r00) * dsfrac) >> 4) + r00)) * dtfrac) >> 4) + ((((r01-r00) * dsfrac) >> 4) + r00)) * (1.0f / 256.0f);
 123                                         color[1] += (float) ((((((((g11-g10) * dsfrac) >> 4) + g10)-((((g01-g00) * dsfrac) >> 4) + g00)) * dtfrac) >> 4) + ((((g01-g00) * dsfrac) >> 4) + g00)) * (1.0f / 256.0f);
 124                                         color[2] += (float) ((((((((b11-b10) * dsfrac) >> 4) + b10)-((((b01-b00) * dsfrac) >> 4) + b00)) * dtfrac) >> 4) + ((((b01-b00) * dsfrac) >> 4) + b00)) * (1.0f / 256.0f);
 125                                 }
 126                                 return true; // success
 127                         }
 128                 }
 129
 130                 // go down back side
 131                 node = node->children[side ^ 1];
 132                 startz = mid;
 133                 distz = endz - startz;
 134                 goto loc0;
 135 //              return RecursiveLightPoint (color, node->children[side ^ 1], x, y, mid, endz);
 136         }
 137 }
 138
 139 // LordHavoc: added light checking to the server
 140 void SV_LightPoint (vec3_t color, vec3_t p)
 141 {
 142         Mod_CheckLoaded(sv.worldmodel);
 143         if (!sv.worldmodel->lightdata)
 144         {
 145                 color[0] = color[1] = color[2] = 255;
 146                 return;
 147         }
 148
 149         color[0] = color[1] = color[2] = 0;
 150         SV_RecursiveLightPoint (color, sv.worldmodel->nodes, p[0], p[1], p[2], p[2] - 65536);
 151 }