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

   1 #include <string.h>
   2 #include "gbaregs.h"
   3 #include "dma.h"
   4 #include "data.h"
   5 #include "util.h"
   6 #include "intr.h"
   7 #include "debug.h"
   8
   9 void gamescr(void)
  10 {
  11         int i, j, tx, ty, angle, depth, nframes, backbuf, zoffs;
  12         static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  13         uint16_t *cdst;
  14         unsigned char *csrc;
  15         uint32_t tun, *tunptr;
  16
  17         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_FB1;
  18
  19         vblperf_start(0xff);
  20
  21         cdst = (uint16_t*)CRAM_BG_ADDR;
  22         csrc = tuncross_cmap;
  23         for(i=0; i<256; i++) {
  24                 *cdst++ = CONV_RGB24_RGB15(csrc[0], csrc[1], csrc[2]);
  25                 csrc += 3;
  26         }
  27
  28         dma_fill16(3, vram[0], 0xffff, 240 * 160 / 2);
  29         dma_fill16(3, vram[1], 0xffff, 240 * 160 / 2);
  30
  31         nframes = 0;
  32         for(;;) {
  33                 backbuf = ++nframes & 1;
  34
  35                 zoffs = nframes << 1;
  36
  37                 cdst = vram[backbuf];
  38                 tunptr = tunmap;
  39                 for(i=0; i<160; i++) {
  40                         cdst++;
  41                         tunptr += 2;
  42                         for(j=1; j<240/2; j++) {
  43                                 uint16_t pp;
  44
  45                                 tun = *tunptr++;
  46                                 angle = tun & 0xffff;
  47                                 depth = tun >> 16;
  48                                 tx = (angle >> 6) & 0x7f;
  49                                 ty = ((depth >> 7) - zoffs) & 0x7f;
  50                                 pp = tuncross_pixels[(ty << 7) + tx];
  51
  52                                 tun = *tunptr++;
  53                                 angle = tun & 0xffff;
  54                                 depth = tun >> 16;
  55                                 tx = (angle >> 6) & 0x7f;
  56                                 ty = ((depth >> 7) - zoffs) & 0x7f;
  57                                 pp |= (uint16_t)tuncross_pixels[(ty << 7) + tx] << 8;
  58
  59                                 *cdst++ = pp;
  60                         }
  61                 }
  62
  63                 vblperf_end();
  64                 wait_vblank();
  65                 present(backbuf);
  66                 vblperf_start();
  67         }
  68 }