2vbl tunnel! 30fps
authorJohn Tsiombikas <nuclear@member.fsf.org>
Tue, 13 Apr 2021 10:09:44 +0000 (13:09 +0300)
committerJohn Tsiombikas <nuclear@member.fsf.org>
Tue, 13 Apr 2021 10:09:44 +0000 (13:09 +0300)
.gitignore
Makefile
src/gamescr.c
src/util.c

index bf8108b..226cf4e 100644 (file)
@@ -16,3 +16,4 @@ data
 *.tar.gz
 *.zip
 pushdata
+link.map
index a83188f..301519d 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -41,7 +41,7 @@ $(bin): $(elf)
        gbafix -r0 $(bin)
 
 $(elf): data/snd.h $(obj) $(libs)
-       $(CC) -o $(elf) $(obj) -specs=gba.specs $(LDFLAGS)
+       $(CC) -o $(elf) $(obj) -specs=gba.specs -Wl,-Map,link.map $(LDFLAGS)
 
 -include $(dep)
 
index 1b11c25..70991e8 100644 (file)
@@ -7,14 +7,17 @@
 #include "intr.h"
 #include "debug.h"
 
+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 };
-       uint16_t *cdst, *top, *bot;
+       int i;
+       uint16_t *cdst;
        unsigned char *csrc;
-       uint32_t tun, *tunptr;
-       unsigned char *tex;
 
        REG_DISPCNT = 4 | DISPCNT_BG2 | DISPCNT_FB1;
 
@@ -37,41 +40,7 @@ void gamescr(void)
        for(;;) {
                backbuf = ++nframes & 1;
 
-               zoffs = nframes << 1;
-
-               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++) {
-                               uint16_t pptop, ppbot;
-
-                               tun = *tunptr++;
-
-                               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) + 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;
-
-                               *top++ = pptop;
-                               *bot++ = ppbot;
-                       }
-                       bot -= 240;
-               }
+               draw_tunnel();
 
                vblperf_end();
                wait_vblank();
@@ -79,3 +48,46 @@ void gamescr(void)
                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;
+
+       zoffs = nframes;
+
+       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) + 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) + 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;
+
+                       *top++ = pptop;
+                       *bot++ = ppbot;
+               }
+               bot -= 240;
+       }
+}
index 292f67c..9bba42f 100644 (file)
@@ -1,13 +1,13 @@
 #include "util.h"
 #include "debug.h"
 
-extern char __data_end__;
-static char *top = &__data_end__;
+extern char __iheap_start;
+static char *top = &__iheap_start;
 
 int iwram_brk(void *addr)
 {
-       if((char*)addr < &__data_end__) {
-               addr = &__data_end__;
+       if((char*)addr < &__iheap_start) {
+               addr = &__iheap_start;
        }
        if(addr > get_sp()) {
                /*return -1;*/