git.mutantstargoat.com Git - gbajam21/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 "data.h"
   7 #include "util.h"
   8 #include "intr.h"
   9 #include "input.h"
  10 #include "sprite.h"
  11 #include "debug.h"
  12
  13 static void draw_tunnel(void);
  14 static void vblank(void);
  15
  16 static int nframes, backbuf;
  17 static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  18 static unsigned char *tex;
  19 static uint16_t bnstate;
  20
  21 #define MAX_SPR         4
  22 static uint16_t oam[4 * MAX_SPR];
  23
  24 static short x = 120, y = 80;
  25 static unsigned char rot;
  26
  27 static int32_t bgmat[4];
  28 static int32_t bgx, bgy;
  29 static int32_t tunrot;
  30
  31 void gamescr(void)
  32 {
  33         int i;
  34         uint16_t *cdst;
  35         unsigned char *csrc;
  36
  37         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_OBJ | DISPCNT_FB1;
  38
  39         vblperf_setcolor(0xff);
  40
  41         /* sprite setup */
  42         spr_setup(16, 16, spr_game_pixels, spr_game_cmap);
  43
  44         wait_vblank();
  45         spr_clear();
  46         spr_oam_clear(oam, 0);
  47         spr_oam_clear(oam, 1);
  48         spr_oam_clear(oam, 2);
  49         spr_oam_clear(oam, 3);
  50
  51         cdst = (uint16_t*)CRAM_BG_ADDR;
  52         csrc = tuncross_cmap;
  53         for(i=0; i<256; i++) {
  54                 *cdst++ = CONV_RGB24_RGB15(csrc[0], csrc[1], csrc[2]);
  55                 csrc += 3;
  56         }
  57
  58         fillblock_16byte(vram[0], 0xffffffff, 240 * 160 / 16);
  59         fillblock_16byte(vram[1], 0xffffffff, 240 * 160 / 16);
  60
  61         tex = iwram_sbrk(32 * 32);
  62         memcpy(tex, tuncross_pixels, 32 * 32);
  63
  64         /*select_input(BN_DPAD);*/
  65
  66         mask(INTR_VBLANK);
  67         screen_vblank = vblank;
  68         unmask(INTR_VBLANK);
  69
  70         nframes = 0;
  71         for(;;) {
  72                 backbuf = ++nframes & 1;
  73
  74                 bnstate = ~REG_KEYINPUT;
  75
  76                 draw_tunnel();
  77
  78                 vblperf_end();
  79                 wait_vblank();
  80                 present(backbuf);
  81                 vblperf_begin();
  82         }
  83 }
  84
  85 __attribute__((noinline, target("arm"), section(".iwram")))
  86 static void draw_tunnel(void)
  87 {
  88         int i, j, tx, ty, angle, depth, zoffs, uoffs, flip;
  89         int tunsweep;
  90         uint16_t pptop, ppbot;
  91         uint16_t *top, *bot;
  92         uint32_t tun, *tunptr;
  93
  94         tunsweep = (SIN(nframes) >> 2) + 64;
  95         if(tunsweep > 127) tunsweep = 127;
  96
  97         flip = tunsweep >= 64;
  98
  99         tunsweep = (tunsweep & 0x3f);
 100         if(tunsweep >= 32) tunsweep = 63 - tunsweep;
 101
 102         zoffs = nframes;
 103
 104         uoffs = tunrot >> 1;
 105
 106         top = vram[backbuf];
 107         bot = vram[backbuf] + 159 * 240 / 2;
 108         tunptr = tunmap + tunsweep * 9600;
 109         if(flip) tunptr += 240/2;
 110         for(i=0; i<80; i++) {
 111                 for(j=0; j<240/2; j++) {
 112                         if(flip) {
 113                                 tun = *--tunptr;
 114                                 tun = (tun >> 16) | (tun << 16);
 115                         } else {
 116                                 tun = *tunptr++;
 117                         }
 118
 119                         angle = tun & 0xff;
 120                         depth = (tun >> 8) & 0xff;
 121                         tx = ((angle >> 1) - uoffs) & 0x1f;
 122                         ty = ((depth >> 1) + zoffs) & 0x1f;
 123                         pptop = tex[(ty << 5) + tx];
 124                         tx = ~((angle >> 1) + uoffs) & 0x1f;
 125                         ppbot = tex[(ty << 5) + tx];
 126
 127                         angle = (tun >> 16) & 0xff;
 128                         depth = (tun >> 24) & 0xff;
 129                         tx = ((angle >> 1) - uoffs) & 0x1f;
 130                         ty = ((depth >> 1) + zoffs) & 0x1f;
 131                         pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
 132                         tx = ~((angle >> 1) + uoffs) & 0x1f;
 133                         ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
 134
 135                         *top++ = pptop;
 136                         *bot++ = ppbot;
 137                 }
 138                 bot -= 240;
 139
 140                 if(flip) tunptr += 240;
 141         }
 142 }
 143
 144 __attribute__((noinline, target("arm"), section(".iwram")))
 145 static void vblank(void)
 146 {
 147         uint16_t bnstate;
 148         int16_t mat[4];
 149         static short gate_speed;
 150
 151         bnstate = ~REG_KEYINPUT;
 152         if(bnstate & BN_DPAD) {
 153                 if(gate_speed < 5) {
 154                         gate_speed++;
 155                 }
 156
 157                 if(bnstate & BN_LEFT) x -= gate_speed;
 158                 if(bnstate & BN_RIGHT) x += gate_speed;
 159                 if(bnstate & BN_UP) y -= gate_speed;
 160                 if(bnstate & BN_DOWN) y += gate_speed;
 161
 162                 if(x < 0) x = 0;
 163                 if(x > 239) x = 239;
 164                 if(y < 0) y = 0;
 165                 if(y > 159) y = 159;
 166         } else {
 167                 gate_speed = 0;
 168         }
 169
 170         if(bnstate & BN_A) rot -= 2;
 171         if(bnstate & BN_B) rot += 2;
 172
 173
 174         spr_oam(oam, 0, 512 + 256, x - 64, y - 64, SPR_256COL | SPR_SZ64 | SPR_DBLSZ |
 175                         SPR_ROTSCL | SPR_ROTSCL_SEL(0));
 176
 177         mat[0] = COS(rot);
 178         mat[1] = -SIN(rot);
 179         mat[2] = SIN(rot);
 180         mat[3] = COS(rot);
 181         spr_transform(oam, 0, mat);
 182
 183
 184         dma_copy16(3, (void*)OAM_ADDR, oam, sizeof oam / 2, 0);
 185 }