Implement mode 3, 4 direct color

twvd · Apr 17, 2024 · 1e01f47 · 1e01f47
1 parent ce4a0cb
commit 1e01f47
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Showing 2 changed files with 15 additions and 2 deletions.
diff --git a/src/snes/ppu/render.rs b/src/snes/ppu/render.rs
@@ -75,6 +75,15 @@ enum WindowMask {
 }
 
 impl PPUState {
+    #[inline(always)]
+    /// Maps direct color value to on-screen color
+    fn directcolor(dc: u8, palette: u8) -> SnesColor {
+        SnesColor::from_rgb5(
+            ((dc & 7) << 2) | ((palette & 1) << 1),
+            (((dc >> 3) & 7) << 2) | (palette & 2),
+            (((dc >> 6) & 3) << 3) | (palette & 4),
+        )
+    }
     #[inline(always)]
     pub fn cgram_to_color(&self, addr: u8) -> SnesColor {
         SnesColor::from(self.cgram[addr as usize])
@@ -89,7 +98,11 @@ impl PPUState {
             BPP::Four => paletteidx * 16,
             BPP::Eight => 0,
         };
-        self.cgram_to_color(palette + idx)
+        if self.cgwsel & (1 << 0) != 0 && self.get_layer_bpp(bg) == BPP::Eight {
+            Self::directcolor(idx, palette)
+        } else {
+            self.cgram_to_color(palette + idx)
+        }
     }
 
     fn sprite_cindex_to_color(&self, tile: &SpriteTile, idx: u8) -> SnesColor {

diff --git a/src/snes/ppu/state.rs b/src/snes/ppu/state.rs
@@ -85,7 +85,7 @@ impl OptEntry {
     }
 }
 
-#[derive(Clone, Copy, Debug, ToPrimitive)]
+#[derive(Clone, Copy, Debug, ToPrimitive, Eq, PartialEq)]
 pub enum BPP {
     // BPP == number of bitplanes
     Two = 2,   // 4 colors