fixed the tunnel precalc to produce a continuous 10 bit depth value

[gbajam21] / src / gamescr.c

diff --git a/src/gamescr.c b/src/gamescr.c
index 452709c..6eee713 100644 (file)
--- a/src/gamescr.c
+++ b/src/gamescr.c
@@ -13,7 +13,7 @@
 static void draw_tunnel(void);
 static void vblank(void);
 
-static int nframes, backbuf;
+static int nframes, num_vbl, backbuf;
 static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
 static unsigned char *tex;
 static uint16_t bnstate;
@@ -24,13 +24,13 @@ static uint16_t oam[4 * MAX_SPR];
 static short x = 120, y = 80;
 static unsigned char rot;
 
-static int32_t bgmat[4];
-static int32_t bgx, bgy;
 static int32_t tunrot;
+static int32_t tunmat[4], tunx, tuny;
 
 void gamescr(void)
 {
        int i;
+       int32_t scale;
        uint16_t *cdst;
        unsigned char *csrc;
 
@@ -61,6 +61,14 @@ void gamescr(void)
        tex = iwram_sbrk(32 * 32);
        memcpy(tex, tuncross_pixels, 32 * 32);
 
+       scale = 0x100;//230;
+       REG_BG2PA = scale;
+       REG_BG2PB = 0;
+       REG_BG2PC = 0;
+       REG_BG2PD = scale;
+       REG_BG2X = (120 << 8) - scale * 120;
+       REG_BG2Y = (80 << 8) - scale * 80;
+
        /*select_input(BN_DPAD);*/
 
        mask(INTR_VBLANK);
@@ -78,67 +86,91 @@ void gamescr(void)
                vblperf_end();
                wait_vblank();
                present(backbuf);
-
-               tunrot = nframes;
-               bgmat[0] = (COS(tunrot) * 280) >> 8;
-               bgmat[1] = (-SIN(tunrot) * 280) >> 8;
-               bgmat[2] = (SIN(tunrot) * 280) >> 8;
-               bgmat[3] = (COS(tunrot) * 280) >> 8;
-               bgx = (120 << 8) - bgmat[0] * 120 + bgmat[1] * -80;
-               bgy = (80 << 8) - bgmat[2] * 120 + bgmat[3] * -80;
-
                vblperf_begin();
        }
 }
 
+#define TUN_U(x)       ((x) & 0x3f)
+#define TUN_V(x)       (((x) >> 7) & 0x1ff)
+
 __attribute__((noinline, target("arm"), section(".iwram")))
 static void draw_tunnel(void)
 {
-       int i, j, tx, ty, angle, depth, zoffs, uoffs;
+       int i, j, tx, ty, u, v, angle, depth, zoffs, uoffs, flip, tunturn;
+       static int tunsweep;
        uint16_t pptop, ppbot;
        uint16_t *top, *bot;
        uint32_t tun, *tunptr;
 
-       zoffs = nframes;
-
-       uoffs = tunrot;
-
-       top = vram[backbuf] + 20;
-       bot = vram[backbuf] + 159 * 240 / 2 + 20;
-       tunptr = tunmap;
-       for(i=0; i<80; i++) {
-               for(j=0; j<160/2; j++) {
-#ifdef VBLBAR
-                       if(j == 160/4) {
-                               tunptr++;
-                               top++;
-                               bot++;
-                               continue;
+       //tunsweep = SIN(nframes) >> 4;
+
+       if((bnstate & BN_RT) && tunsweep > -31) tunsweep--;
+       if((bnstate & BN_LT) && tunsweep < 31) tunsweep++;
+
+       flip = tunsweep < 0;
+       tunturn = abs(tunsweep) & 0x1f;
+
+       zoffs = num_vbl;
+       uoffs = 0;//(flip ? -num_vbl : num_vbl) >> 2;
+
+       top = vram[backbuf];
+       bot = vram[backbuf] + 159 * 240 / 2;
+       tunptr = tunmap + tunturn * 9600;
+
+       if(flip) {
+               tunptr += 240/2;
+               for(i=0; i<80; i++) {
+                       for(j=0; j<240/2; j++) {
+                               tun = *--tunptr;
+
+                               angle = TUN_U(tun >> 16);
+                               depth = TUN_V(tun >> 16);
+                               tx = ~(angle - uoffs) & 0x1f;
+                               ty = (depth + zoffs) & 0x1f;
+                               pptop = tex[(ty << 5) + tx];
+                               tx = (angle + uoffs) & 0x1f;
+                               ppbot = tex[(ty << 5) + tx];
+
+                               angle = TUN_U(tun);
+                               depth = TUN_V(tun);
+                               tx = ~(angle - uoffs) & 0x1f;
+                               ty = (depth + zoffs) & 0x1f;
+                               pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
+                               tx = (angle + uoffs) & 0x1f;
+                               ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
+
+                               *top++ = pptop;
+                               *bot++ = ppbot;
+                       }
+                       bot -= 240;
+                       tunptr += 240;
+               }
+       } else {
+               for(i=0; i<80; i++) {
+                       for(j=0; j<240/2; j++) {
+                               tun = *tunptr++;
+
+                               angle = TUN_U(tun);
+                               depth = TUN_V(tun);
+                               tx = (angle - uoffs) & 0x1f;
+                               ty = (depth + zoffs) & 0x1f;
+                               pptop = tex[(ty << 5) + tx];
+                               tx = ~(angle + uoffs) & 0x1f;
+                               ppbot = tex[(ty << 5) + tx];
+
+                               angle = TUN_U(tun >> 16);
+                               depth = TUN_V(tun >> 16);
+                               tx = (angle - uoffs) & 0x1f;
+                               ty = (depth + zoffs) & 0x1f;
+                               pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
+                               tx = ~(angle + uoffs) & 0x1f;
+                               ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
+
+                               *top++ = pptop;
+                               *bot++ = ppbot;
                        }
-#endif
-                       tun = *tunptr++;
-
-                       angle = tun & 0xff;
-                       depth = (tun >> 8) & 0xff;
-                       tx = ((angle >> 1) - uoffs) & 0x1f;
-                       ty = ((depth >> 1) + zoffs) & 0x1f;
-                       pptop = tex[(ty << 5) + tx];
-                       tx = ~((angle >> 1) + uoffs) & 0x1f;
-                       ppbot = tex[(ty << 5) + tx];
-
-                       angle = (tun >> 16) & 0xff;
-                       depth = (tun >> 24) & 0xff;
-                       tx = ((angle >> 1) - uoffs) & 0x1f;
-                       ty = ((depth >> 1) + zoffs) & 0x1f;
-                       pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
-                       tx = ~((angle >> 1) + uoffs) & 0x1f;
-                       ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
-
-                       *top++ = pptop;
-                       *bot++ = ppbot;
+                       bot -= 240;
                }
-               top += 40;
-               bot -= 240 - 40;
        }
 }
 
@@ -149,12 +181,7 @@ static void vblank(void)
        int16_t mat[4];
        static short gate_speed;
 
-       REG_BG2PA = bgmat[0];
-       REG_BG2PB = bgmat[1];
-       REG_BG2PC = bgmat[2];
-       REG_BG2PD = bgmat[3];
-       REG_BG2X = bgx;
-       REG_BG2Y = bgy;
+       num_vbl++;
 
        bnstate = ~REG_KEYINPUT;
        if(bnstate & BN_DPAD) {
@@ -182,10 +209,10 @@ static void vblank(void)
        spr_oam(oam, 0, 512 + 256, x - 64, y - 64, SPR_256COL | SPR_SZ64 | SPR_DBLSZ |
                        SPR_ROTSCL | SPR_ROTSCL_SEL(0));
 
-       mat[0] = COS(rot) << 1;
-       mat[1] = -SIN(rot) << 1;
-       mat[2] = SIN(rot) << 1;
-       mat[3] = COS(rot) << 1;
+       mat[0] = COS(rot);
+       mat[1] = -SIN(rot);
+       mat[2] = SIN(rot);
+       mat[3] = COS(rot);
        spr_transform(oam, 0, mat);