model: enable 4-color and 16-color modes

Makefile

@@ -1,4 +1,4 @@
-OPT = -Os
+OPT = -O3
 
 all: cartridge.bin
 

arm9/examples/ulala.c

@@ -461,8 +461,8 @@ void main()
     while (io_registers.a.GXSTAT & GXSTAT__geometry_engine_busy);
 
     // wait for the end of the current frame
-    while (io_registers.a.VCOUNT != 262);
-    while (io_registers.a.VCOUNT == 262);
+    //while (io_registers.a.VCOUNT != 262);
+    //while (io_registers.a.VCOUNT == 262);
 
     // swap buffers
     io_registers.a.SWAP_BUFFERS = 0;

gen/color_convert.py

@@ -66,7 +66,27 @@ if palette is None:
         convert_colors(f, pixels)
 else:
     with open(out_file, 'wb') as f:
-        for pixel in pixels:
-            f.write(struct.pack("<B", pixel))
+        if len(palette) <= 4:
+            for i in range(len(pixels) // 4):
+                a = pixels[i * 4 + 0]
+                b = pixels[i * 4 + 1]
+                c = pixels[i * 4 + 2]
+                d = pixels[i * 4 + 3]
+                assert a <= 3 and b <= 3 and c <= 3 and d <= 3, (a, b, c, d)
+                pixel = (d << 6) | (c << 4) | (b << 2) | (a << 0)
+                f.write(struct.pack("<B", pixel))
+        elif len(palette) <= 16:
+            for i in range(len(pixels) // 2):
+                a = pixels[i * 2 + 0]
+                b = pixels[i * 2 + 1]
+                assert a <= 15 and b <= 15, (a, b)
+                pixel = (b << 4) | (a << 0)
+                f.write(struct.pack("<B", pixel))
+        elif len(palette) <= 256:
+            for pixel in pixels:
+                assert pixel <= 255
+                f.write(struct.pack("<B", pixel))
+        else:
+            assert False, len(palette)
     with open(out_file + '.pal', 'wb') as f:
         convert_colors(f, [(*c, 255) for c in palette])

gen/render_material_textures.py

@@ -45,7 +45,6 @@ class Offset:
 
 def round_up_colors(name, colors):
     assert colors != 0, (name, colors)
-    return 256
     if colors <= 4:
         return 4
     if colors <= 16:

model/ulala/material.h

@@ -102,14 +102,14 @@ struct material_descriptor material[] = {
       .start = (uint8_t *)&_binary_p_ref_or_data_pal_start,
       .size = (int)&_binary_p_ref_or_data_pal_size,
       .vram_offset = 1472,
-      .palette_size = 256,
+      .palette_size = 4,
     },
   },
   [u_lb] = {
     .pixel = {
       .start = (uint8_t *)&_binary_u_lb_data_start,
       .size = (int)&_binary_u_lb_data_size,
-      .vram_offset = 95232,
+      .vram_offset = 92160,
       .width = 64,
       .height = 64,
     },