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, num_vbl, backbuf;
  17 static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
  18 static unsigned char *tex, *shadelut;
  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 tunrot;
  28 static int32_t tunmat[4], tunx, tuny;
  29
  30 void gamescr(void)
  31 {
  32         int i;
  33         int32_t scale;
  34         uint16_t *cdst;
  35         unsigned char *csrc;
  36
  37         REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_OBJ | DISPCNT_FB1;
  38
  39         vblperf_setcolor(0xff);//192);
  40
  41         /* sprite setup */
  42         spr_setup(32, 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         shadelut = iwram_sbrk(256 * 8);
  64         memcpy(shadelut, tuncross_shade, 256 * 8);
  65
  66         scale = 0x100;//230;
  67         REG_BG2PA = scale;
  68         REG_BG2PB = 0;
  69         REG_BG2PC = 0;
  70         REG_BG2PD = scale;
  71         REG_BG2X = (120 << 8) - scale * 120;
  72         REG_BG2Y = (80 << 8) - scale * 80;
  73
  74         /*select_input(BN_DPAD);*/
  75
  76         mask(INTR_VBLANK);
  77         screen_vblank = vblank;
  78         unmask(INTR_VBLANK);
  79
  80         nframes = 0;
  81         for(;;) {
  82                 backbuf = ++nframes & 1;
  83
  84                 bnstate = ~REG_KEYINPUT;
  85
  86                 draw_tunnel();
  87
  88                 vblperf_end();
  89                 wait_vblank();
  90                 present(backbuf);
  91                 vblperf_begin();
  92         }
  93 }
  94
  95 #define TUN_U(x)        ((x) & 0x3f)
  96 #define TUN_V(x)        (((x) >> 6) & 0x3ff)
  97 #define TEXEL(x, y, lvl) \
  98         shadelut[((int)tex[((y) << 5) + (x)] << 3) + (lvl)]
  99
 100 __attribute__((noinline, target("arm"), section(".iwram")))
 101 static void draw_tunnel(void)
 102 {
 103         int i, j, tx, ty, u, v, angle, depth, zoffs, uoffs, flip, tunturn, shade;
 104         static int tunsweep;
 105         uint16_t pptop, ppbot;
 106         uint16_t *top, *bot;
 107         uint32_t tun, *tunptr;
 108
 109         //tunsweep = SIN(nframes) >> 4;
 110
 111         if((bnstate & BN_RT) && tunsweep > -31) tunsweep--;
 112         if((bnstate & BN_LT) && tunsweep < 31) tunsweep++;
 113
 114         flip = tunsweep < 0;
 115         tunturn = abs(tunsweep) & 0x1f;
 116
 117         zoffs = num_vbl;
 118         uoffs = (flip ? -num_vbl : num_vbl) >> 1;
 119
 120         top = vram[backbuf];
 121         bot = vram[backbuf] + 159 * 240 / 2;
 122         tunptr = tunmap + tunturn * 9600;
 123
 124         if(flip) {
 125                 tunptr += 240/2;
 126                 for(i=0; i<80; i++) {
 127                         for(j=0; j<240/2; j++) {
 128                                 tun = *--tunptr;
 129
 130                                 angle = TUN_U(tun >> 16);
 131                                 depth = TUN_V(tun >> 16);
 132                                 shade = depth >> 7;
 133                                 tx = ~(angle - uoffs) & 0x1f;
 134                                 ty = ((depth >> 1) + zoffs) & 0x1f;
 135                                 pptop = TEXEL(tx, ty, shade);
 136                                 tx = (angle + uoffs) & 0x1f;
 137                                 ppbot = TEXEL(tx, ty, shade);
 138
 139                                 angle = TUN_U(tun);
 140                                 depth = TUN_V(tun);
 141                                 shade = depth >> 7;
 142                                 tx = ~(angle - uoffs) & 0x1f;
 143                                 ty = ((depth >> 1) + zoffs) & 0x1f;
 144                                 pptop |= (uint16_t)TEXEL(tx, ty, shade) << 8;
 145                                 tx = (angle + uoffs) & 0x1f;
 146                                 ppbot |= (uint16_t)TEXEL(tx, ty, shade) << 8;
 147
 148                                 *top++ = pptop;
 149                                 *bot++ = ppbot;
 150                         }
 151                         bot -= 240;
 152                         tunptr += 240;
 153                 }
 154         } else {
 155                 for(i=0; i<80; i++) {
 156                         for(j=0; j<240/2; j++) {
 157                                 tun = *tunptr++;
 158
 159                                 angle = TUN_U(tun);
 160                                 depth = TUN_V(tun);
 161                                 shade = depth >> 7;
 162                                 tx = (angle - uoffs) & 0x1f;
 163                                 ty = ((depth >> 1) + zoffs) & 0x1f;
 164                                 pptop = TEXEL(tx, ty, shade);
 165                                 tx = ~(angle + uoffs) & 0x1f;
 166                                 ppbot = TEXEL(tx, ty, shade);
 167
 168                                 angle = TUN_U(tun >> 16);
 169                                 depth = TUN_V(tun >> 16);
 170                                 shade = depth >> 7;
 171                                 tx = (angle - uoffs) & 0x1f;
 172                                 ty = ((depth >> 1) + zoffs) & 0x1f;
 173                                 pptop |= (uint16_t)TEXEL(tx, ty, shade) << 8;
 174                                 tx = ~(angle + uoffs) & 0x1f;
 175                                 ppbot |= (uint16_t)TEXEL(tx, ty, shade) << 8;
 176
 177                                 *top++ = pptop;
 178                                 *bot++ = ppbot;
 179                         }
 180                         bot -= 240;
 181                 }
 182         }
 183 }
 184
 185 __attribute__((noinline, target("arm"), section(".iwram")))
 186 static void vblank(void)
 187 {
 188         uint16_t bnstate;
 189         int16_t mat[4];
 190         static short gate_speed;
 191
 192         num_vbl++;
 193
 194         bnstate = ~REG_KEYINPUT;
 195         if(bnstate & BN_DPAD) {
 196                 if(gate_speed < 5) {
 197                         gate_speed++;
 198                 }
 199
 200                 if(bnstate & BN_LEFT) x -= gate_speed;
 201                 if(bnstate & BN_RIGHT) x += gate_speed;
 202                 if(bnstate & BN_UP) y -= gate_speed;
 203                 if(bnstate & BN_DOWN) y += gate_speed;
 204
 205                 if(x < 0) x = 0;
 206                 if(x > 239) x = 239;
 207                 if(y < 0) y = 0;
 208                 if(y > 159) y = 159;
 209         } else {
 210                 gate_speed = 0;
 211         }
 212
 213         if(bnstate & BN_A) rot -= 2;
 214         if(bnstate & BN_B) rot += 2;
 215
 216
 217         spr_oam(oam, 0, 512, x - 64, y - 64, SPR_SZ64 | SPR_DBLSZ |
 218                         SPR_ROTSCL | SPR_ROTSCL_SEL(0));
 219
 220         mat[0] = COS(rot);
 221         mat[1] = -SIN(rot);
 222         mat[2] = SIN(rot);
 223         mat[3] = COS(rot);
 224         spr_transform(oam, 0, mat);
 225
 226
 227         dma_copy16(3, (void*)OAM_ADDR, oam, sizeof oam / 2, 0);
 228 }