2vbl tunnel! 30fps

[gbajam21] / src / gamescr.c

diff --git a/src/gamescr.c b/src/gamescr.c
index bd73b1b..70991e8 100644 (file)
--- a/src/gamescr.c
+++ b/src/gamescr.c
@@ -7,19 +7,21 @@
 #include "intr.h"
 #include "debug.h"
 
-static unsigned char tex[32 * 32] __attribute__((section(".iwram")));
+static void draw_tunnel(void);
+
+static int nframes, backbuf;
+static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
+static unsigned char *tex;
 
 void gamescr(void)
 {
-       int i, j, tx, ty, angle, depth, nframes, backbuf, zoffs;
-       static uint16_t *vram[] = { (uint16_t*)VRAM_LFB_FB0_ADDR, (uint16_t*)VRAM_LFB_FB1_ADDR };
+       int i;
        uint16_t *cdst;
        unsigned char *csrc;
-       uint32_t tun, *tunptr, *tuncache;
 
        REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_FB1;
 
-       vblperf_start(0xff);
+       vblperf_setcolor(0xff);
 
        cdst = (uint16_t*)CRAM_BG_ADDR;
        csrc = tuncross_cmap;
@@ -31,45 +33,61 @@ void gamescr(void)
        fillblock_16byte(vram[0], 0xffffffff, 240 * 160 / 16);
        fillblock_16byte(vram[1], 0xffffffff, 240 * 160 / 16);
 
-       if(!(tuncache = malloc(240 * 160 * 2))) {
-               panic(get_pc(), "failed to allocate tuntab");
-       }
-       memcpy(tuncache, tunmap, 240 * 160 * 2);
+       tex = iwram_sbrk(32 * 32);
        memcpy(tex, tuncross_pixels, 32 * 32);
 
        nframes = 0;
        for(;;) {
                backbuf = ++nframes & 1;
 
-               zoffs = nframes << 1;
+               draw_tunnel();
+
+               vblperf_end();
+               wait_vblank();
+               present(backbuf);
+               vblperf_begin();
+       }
+}
+
+__attribute__((noinline, target("arm"), section(".iwram")))
+static void draw_tunnel(void)
+{
+       int i, j, tx, ty, angle, depth, zoffs;
+       uint16_t pptop, ppbot;
+       uint16_t *top, *bot;
+       uint32_t tun, *tunptr;
 
-               cdst = vram[backbuf];
-               tunptr = tuncache;
-               for(i=0; i<160 * 240 / 2; i++) {
-                       //for(j=1; j<240/2; j++) {
-                               uint16_t pp;
+       zoffs = nframes;
 
-                               tun = *tunptr++;
+       top = vram[backbuf];
+       bot = vram[backbuf] + 159 * 240 / 2;
+       tunptr = tunmap;
+       for(i=0; i<80; i++) {
+               top++;
+               bot++;
+               tunptr++;
+               for(j=1; j<240/2; j++) {
+                       tun = *tunptr++;
 
-                               angle = tun & 0xff;
-                               depth = (tun >> 8) & 0xff;
-                               tx = (angle >> 1) & 0x1f;
-                               ty = ((depth >> 1) + zoffs) & 0x1f;
-                               pp = tex[(ty << 5) + tx];
+                       angle = tun & 0xff;
+                       depth = (tun >> 8) & 0xff;
+                       tx = ((angle >> 1) + zoffs) & 0x1f;
+                       ty = ((depth >> 1) + zoffs) & 0x1f;
+                       pptop = tex[(ty << 5) + tx];
+                       tx = ((angle >> 1) - zoffs) & 0x1f;
+                       ppbot = tex[(ty << 5) + tx];
 
-                               angle = (tun >> 16) & 0xff;
-                               depth = (tun >> 24) & 0xff;
-                               tx = (angle >> 1) & 0x1f;
-                               ty = ((depth >> 1) + zoffs) & 0x1f;
-                               pp |= (uint16_t)tex[(ty << 5) + tx] << 8;
+                       angle = (tun >> 16) & 0xff;
+                       depth = (tun >> 24) & 0xff;
+                       tx = ((angle >> 1) + zoffs) & 0x1f;
+                       ty = ((depth >> 1) + zoffs) & 0x1f;
+                       pptop |= (uint16_t)tex[(ty << 5) + tx] << 8;
+                       tx = ((angle >> 1) - zoffs) & 0x1f;
+                       ppbot |= (uint16_t)tex[(ty << 5) + tx] << 8;
 
-                               *cdst++ = pp;
-                       //}
+                       *top++ = pptop;
+                       *bot++ = ppbot;
                }
-
-               vblperf_end();
-               wait_vblank();
-               present(backbuf);
-               vblperf_begin();
+               bot -= 240;
        }
 }