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 static unsigned char tex[32 * 32] __attribute__((section(".iwram")));
  11
  12 void gamescr(void)
  13 {
  14         int i, j, tx, ty, angle, depth, nframes, backbuf, zoffs;
  15         static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  16         uint16_t *cdst, *top, *bot;
  17         unsigned char *csrc;
  18         uint32_t tun, *tunptr;
  19
  20         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_FB1;
  21
  22         vblperf_start(0xff);
  23
  24         cdst = (uint16_t*)CRAM_BG_ADDR;
  25         csrc = tuncross_cmap;
  26         for(i=0; i<256; i++) {
  27                 *cdst++ = CONV_RGB24_RGB15(csrc[0], csrc[1], csrc[2]);
  28                 csrc += 3;
  29         }
  30
  31         fillblock_16byte(vram[0], 0xffffffff, 240 * 160 / 16);
  32         fillblock_16byte(vram[1], 0xffffffff, 240 * 160 / 16);
  33
  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                         for(j=0; j<240/2; j++) {
  47                                 uint16_t pptop, ppbot;
  48
  49                                 tun = *tunptr++;
  50
  51                                 angle = tun & 0xff;
  52                                 depth = (tun >> 8) & 0xff;
  53                                 tx = ((angle >> 1) + zoffs) & 0x1f;
  54                                 ty = ((depth >> 1) + zoffs) & 0x1f;
  55                                 pptop = tex[(ty << 5) + tx];
  56                                 tx = ((angle >> 1) - zoffs) & 0x1f;
  57                                 ppbot = tex[(ty << 5) + tx];
  58
  59                                 angle = (tun >> 16) & 0xff;
  60                                 depth = (tun >> 24) & 0xff;
  61                                 tx = ((angle >> 1) + zoffs) & 0x1f;
  62                                 ty = ((depth >> 1) + zoffs) & 0x1f;
  63                                 pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
  64                                 tx = ((angle >> 1) - zoffs) & 0x1f;
  65                                 ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
  66
  67                                 *top++ = pptop;
  68                                 *bot++ = ppbot;
  69                         }
  70                         bot -= 240;
  71                 }
  72
  73                 vblperf_end();
  74                 wait_vblank();
  75                 present(backbuf);
  76                 vblperf_begin();
  77         }
  78 }