git.mutantstargoat.com Git - gbajam22/blob - src/gamescr.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include "gbaregs.h"
   4 #include "game.h"
   5 #include "dma.h"
   6 #include "util.h"
   7 #include "intr.h"
   8 #include "input.h"
   9 #include "sprite.h"
  10 #include "debug.h"
  11
  12 static void draw(void);
  13 static void vblank(void);
  14
  15 static int nframes, num_vbl, backbuf;
  16 static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  17 static uint16_t bnstate;
  18
  19
  20 void gamescr(void)
  21 {
  22         int i;
  23
  24         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_OBJ | DISPCNT_FB1;
  25
  26         vblperf_setcolor(0xff);//192);
  27
  28         fillblock_16byte(vram[0], 0xffffffff, 240 * 160 / 16);
  29         fillblock_16byte(vram[1], 0xffffffff, 240 * 160 / 16);
  30
  31         mask(INTR_VBLANK);
  32         screen_vblank = vblank;
  33         unmask(INTR_VBLANK);
  34
  35         nframes = 0;
  36         for(;;) {
  37                 backbuf = ++nframes & 1;
  38
  39                 bnstate = ~REG_KEYINPUT;
  40
  41                 draw();
  42
  43                 vblperf_end();
  44                 wait_vblank();
  45                 present(backbuf);
  46                 vblperf_begin();
  47         }
  48 }
  49
  50 static void draw(void)
  51 {
  52         int i, j;
  53         uint16_t pix;
  54         uint16_t *fb = vram[backbuf];
  55
  56         for(i=0; i<160; i++) {
  57                 for(j=0; j<240/2; j++) {
  58                         pix = ((i^j) << 1) & 0xff;
  59                         pix |= (i^j) << 9;
  60                         *fb++ = pix;
  61                 }
  62         }
  63 }
  64
  65 __attribute__((noinline, target("arm"), section(".iwram")))
  66 static void vblank(void)
  67 {
  68         num_vbl++;
  69 }