patch for binjgb and appling it in build script (#54)

binjgb.patch

@@ -0,0 +1,24 @@
+diff --git a/src/emulator.c b/src/emulator.c
+index 0329ccf..a91ef67 100644
+--- a/src/emulator.c
++++ b/src/emulator.c
+@@ -5209,13 +5209,15 @@ void emulator_render_vram(Emulator* e, u32* buffer) {
+ void emulator_render_background(Emulator* e, u32* buffer, int type) {
+   memset(buffer, 0, sizeof(u32) * 256 * 256);
+   int bank = 0;
+-  int tile_map = (type & 1) ? 0x400 : 0;
++  int tile_map = 0x1800 + ((type & 1) ? 0x400 : 0);
+   for (int ty = 0; ty < 32; ty++) {
+     for (int tx = 0; tx < 32; tx++) {
++      u8 tile = VRAM.data[tile_map + tx + ty * 32];
++      int offset = 0;
++      if(tile < 128)
++         offset = (LCDC.bg_tile_data_select ==  TILE_DATA_8000_8FFF) ? 0 : 0x1000;
+       for (int row = 0; row < 8; row++) {
+-        int tile = VRAM.data[0x1800 + tile_map + tx + ty * 32];
+-        // TODO: LCDC bit 4
+-        int n = tile * 16 + row * 2;
++        int n = offset + tile * 16 + row * 2;
+         u8 a = VRAM.data[n];
+         u8 b = VRAM.data[n + 1];
+         for (int x = 0; x < 8; x++) {

build-binjgb.sh

@@ -8,6 +8,9 @@ if [[ "$(which emsdk)" == "" ]]; then
 fi
 
 cd binjgb
+
+patch -p1 < ../binjgb.patch
+
 ! mkdir out
 cd out
 cmake -E env LDFLAGS='-s EXPORT_ES6=1' \