Games/Quake/d_part.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 // d_part.c: software driver module for drawing particles
  21
  22 #include "quakedef.h"
  23 #include "d_local.h"
  24
  25
  26 /*
  27 ==============
  28 D_EndParticles
  29 ==============
  30 */
  31 void D_EndParticles (void)
  32 {
  33 // not used by software driver
  34 }
  35
  36
  37 /*
  38 ==============
  39 D_StartParticles
  40 ==============
  41 */
  42 void D_StartParticles (void)
  43 {
  44 // not used by software driver
  45 }
  46
  47
  48 #if     !id386
  49
  50 /*
  51 ==============
  52 D_DrawParticle
  53 ==============
  54 */
  55 void D_DrawParticle (particle_t *pparticle)
  56 {
  57         vec3_t  local, transformed;
  58         float   zi;
  59         byte    *pdest;
  60         short   *pz;
  61         int             i, izi, pix, count, u, v;
  62
  63 // transform point
  64         VectorSubtract (pparticle->org, r_origin, local);
  65
  66         transformed[0] = DotProduct(local, r_pright);
  67         transformed[1] = DotProduct(local, r_pup);
  68         transformed[2] = DotProduct(local, r_ppn);
  69
  70         if (transformed[2] < PARTICLE_Z_CLIP)
  71                 return;
  72
  73 // project the point
  74 // FIXME: preadjust xcenter and ycenter
  75         zi = 1.0 / transformed[2];
  76         u = (int)(xcenter + zi * transformed[0] + 0.5);
  77         v = (int)(ycenter - zi * transformed[1] + 0.5);
  78
  79         if ((v > d_vrectbottom_particle) ||
  80                 (u > d_vrectright_particle) ||
  81                 (v < d_vrecty) ||
  82                 (u < d_vrectx))
  83         {
  84                 return;
  85         }
  86
  87         pz = d_pzbuffer + (d_zwidth * v) + u;
  88         pdest = d_viewbuffer + d_scantable[v] + u;
  89         izi = (int)(zi * 0x8000);
  90
  91         pix = izi >> d_pix_shift;
  92
  93         if (pix < d_pix_min)
  94                 pix = d_pix_min;
  95         else if (pix > d_pix_max)
  96                 pix = d_pix_max;
  97
  98         switch (pix)
  99         {
 100         case 1:
 101                 count = 1 << d_y_aspect_shift;
 102
 103                 for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
 104                 {
 105                         if (pz[0] <= izi)
 106                         {
 107                                 pz[0] = izi;
 108                                 pdest[0] = pparticle->color;
 109                         }
 110                 }
 111                 break;
 112
 113         case 2:
 114                 count = 2 << d_y_aspect_shift;
 115
 116                 for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
 117                 {
 118                         if (pz[0] <= izi)
 119                         {
 120                                 pz[0] = izi;
 121                                 pdest[0] = pparticle->color;
 122                         }
 123
 124                         if (pz[1] <= izi)
 125                         {
 126                                 pz[1] = izi;
 127                                 pdest[1] = pparticle->color;
 128                         }
 129                 }
 130                 break;
 131
 132         case 3:
 133                 count = 3 << d_y_aspect_shift;
 134
 135                 for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
 136                 {
 137                         if (pz[0] <= izi)
 138                         {
 139                                 pz[0] = izi;
 140                                 pdest[0] = pparticle->color;
 141                         }
 142
 143                         if (pz[1] <= izi)
 144                         {
 145                                 pz[1] = izi;
 146                                 pdest[1] = pparticle->color;
 147                         }
 148
 149                         if (pz[2] <= izi)
 150                         {
 151                                 pz[2] = izi;
 152                                 pdest[2] = pparticle->color;
 153                         }
 154                 }
 155                 break;
 156
 157         case 4:
 158                 count = 4 << d_y_aspect_shift;
 159
 160                 for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
 161                 {
 162                         if (pz[0] <= izi)
 163                         {
 164                                 pz[0] = izi;
 165                                 pdest[0] = pparticle->color;
 166                         }
 167
 168                         if (pz[1] <= izi)
 169                         {
 170                                 pz[1] = izi;
 171                                 pdest[1] = pparticle->color;
 172                         }
 173
 174                         if (pz[2] <= izi)
 175                         {
 176                                 pz[2] = izi;
 177                                 pdest[2] = pparticle->color;
 178                         }
 179
 180                         if (pz[3] <= izi)
 181                         {
 182                                 pz[3] = izi;
 183                                 pdest[3] = pparticle->color;
 184                         }
 185                 }
 186                 break;
 187
 188         default:
 189                 count = pix << d_y_aspect_shift;
 190
 191                 for ( ; count ; count--, pz += d_zwidth, pdest += screenwidth)
 192                 {
 193                         for (i=0 ; i<pix ; i++)
 194                         {
 195                                 if (pz[i] <= izi)
 196                                 {
 197                                         pz[i] = izi;
 198                                         pdest[i] = pparticle->color;
 199                                 }
 200                         }
 201                 }
 202                 break;
 203         }
 204 }
 205
 206 #endif  // !id386
 207