tunnel rotation with lower-res scaled-up tunnel

[gbajam21] / src / gamescr.c

diff --git a/src/gamescr.c b/src/gamescr.c
index ec4f353..452709c 100644 (file)
--- a/src/gamescr.c
+++ b/src/gamescr.c
@@ -24,6 +24,10 @@ 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;
+
 void gamescr(void)
 {
        int i;
@@ -74,73 +78,67 @@ 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();
        }
 }
 
-static int32_t bgmat[4];
-static int32_t bgx, bgy;
-
 __attribute__((noinline, target("arm"), section(".iwram")))
 static void draw_tunnel(void)
 {
-       static short uoffs;
-       int i, j, tx, ty, angle, depth, zoffs;
+       int i, j, tx, ty, angle, depth, zoffs, uoffs;
        uint16_t pptop, ppbot;
        uint16_t *top, *bot;
        uint32_t tun, *tunptr;
 
        zoffs = nframes;
 
-       if(bnstate & BN_LT) uoffs++;
-       if(bnstate & BN_RT) uoffs--;
-
-       bgmat[0] = COS(uoffs) << 1;
-       bgmat[1] = -SIN(uoffs) << 1;
-       bgmat[2] = SIN(uoffs) << 1;
-       bgmat[3] = COS(uoffs) << 1;
-       bgx = (120 << 8) - bgmat[0] * 120 + bgmat[1] * -80;
-       bgy = (80 << 8) - bgmat[2] * 120 + bgmat[3] * -80;
+       uoffs = tunrot;
 
-       top = vram[backbuf];
-       bot = vram[backbuf] + 159 * 240 / 2;
+       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
-               top++;
-               bot++;
-               tunptr++;
-
-               for(j=1; j<240/2; j++) {
-#else
-               for(j=0; j<240/2; j++) {
+                       if(j == 160/4) {
+                               tunptr++;
+                               top++;
+                               bot++;
+                               continue;
+                       }
 #endif
                        tun = *tunptr++;
 
                        angle = tun & 0xff;
                        depth = (tun >> 8) & 0xff;
-//                     tx = ((angle >> 1) - uoffs) & 0x1f;
-                       tx = (angle >> 1) & 0x1f;
+                       tx = ((angle >> 1) - uoffs) & 0x1f;
                        ty = ((depth >> 1) + zoffs) & 0x1f;
                        pptop = tex[(ty << 5) + tx];
-//                     tx = ~((angle >> 1) + uoffs) & 0x1f;
-                       tx = ~(angle >> 1) & 0x1f;
+                       tx = ~((angle >> 1) + uoffs) & 0x1f;
                        ppbot = tex[(ty << 5) + tx];
 
                        angle = (tun >> 16) & 0xff;
                        depth = (tun >> 24) & 0xff;
-//                     tx = ((angle >> 1) - uoffs) & 0x1f;
-                       tx = (angle >> 1) & 0x1f;
+                       tx = ((angle >> 1) - uoffs) & 0x1f;
                        ty = ((depth >> 1) + zoffs) & 0x1f;
                        pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
-//                     tx = ~((angle >> 1) + uoffs) & 0x1f;
-                       tx = ~(angle >> 1) & 0x1f;
+                       tx = ~((angle >> 1) + uoffs) & 0x1f;
                        ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
 
                        *top++ = pptop;
                        *bot++ = ppbot;
                }
-               bot -= 240;
+               top += 40;
+               bot -= 240 - 40;
        }
 }
 
@@ -180,6 +178,7 @@ static void vblank(void)
        if(bnstate & BN_A) rot -= 2;
        if(bnstate & BN_B) rot += 2;
 
+
        spr_oam(oam, 0, 512 + 256, x - 64, y - 64, SPR_256COL | SPR_SZ64 | SPR_DBLSZ |
                        SPR_ROTSCL | SPR_ROTSCL_SEL(0));