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