git.mutantstargoat.com Git - gbajam21/blob - src/gamescr.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include "gbaregs.h"
   4 #include "dma.h"
   5 #include "data.h"
   6 #include "util.h"
   7 #include "intr.h"
   8 #include "debug.h"
   9
  10 void gamescr(void)
  11 {
  12         int i, j, tx, ty, angle, depth, nframes, backbuf, zoffs;
  13         static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  14         uint16_t *cdst, *top, *bot;
  15         unsigned char *csrc;
  16         uint32_t tun, *tunptr;
  17         unsigned char *tex;
  18
  19         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_FB1;
  20
  21         vblperf_start(0xff);
  22
  23         cdst = (uint16_t*)CRAM_BG_ADDR;
  24         csrc = tuncross_cmap;
  25         for(i=0; i<256; i++) {
  26                 *cdst++ = CONV_RGB24_RGB15(csrc[0], csrc[1], csrc[2]);
  27                 csrc += 3;
  28         }
  29
  30         fillblock_16byte(vram[0], 0xffffffff, 240 * 160 / 16);
  31         fillblock_16byte(vram[1], 0xffffffff, 240 * 160 / 16);
  32
  33         tex = iwram_sbrk(32 * 32);
  34         memcpy(tex, tuncross_pixels, 32 * 32);
  35
  36         nframes = 0;
  37         for(;;) {
  38                 backbuf = ++nframes & 1;
  39
  40                 zoffs = nframes << 1;
  41
  42                 top = vram[backbuf];
  43                 bot = vram[backbuf] + 159 * 240 / 2;
  44                 tunptr = tunmap;
  45                 for(i=0; i<80; i++) {
  46                         top++;
  47                         bot++;
  48                         tunptr++;
  49                         for(j=1; j<240/2; j++) {
  50                                 uint16_t pptop, ppbot;
  51
  52                                 tun = *tunptr++;
  53
  54                                 angle = tun & 0xff;
  55                                 depth = (tun >> 8) & 0xff;
  56                                 tx = ((angle >> 1) + zoffs) & 0x1f;
  57                                 ty = ((depth >> 1) + zoffs) & 0x1f;
  58                                 pptop = tex[(ty << 5) + tx];
  59                                 tx = ((angle >> 1) - zoffs) & 0x1f;
  60                                 ppbot = tex[(ty << 5) + tx];
  61
  62                                 angle = (tun >> 16) & 0xff;
  63                                 depth = (tun >> 24) & 0xff;
  64                                 tx = ((angle >> 1) + zoffs) & 0x1f;
  65                                 ty = ((depth >> 1) + zoffs) & 0x1f;
  66                                 pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
  67                                 tx = ((angle >> 1) - zoffs) & 0x1f;
  68                                 ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
  69
  70                                 *top++ = pptop;
  71                                 *bot++ = ppbot;
  72                         }
  73                         bot -= 240;
  74                 }
  75
  76                 vblperf_end();
  77                 wait_vblank();
  78                 present(backbuf);
  79                 vblperf_begin();
  80         }
  81 }