From ba9a601874687eb5739f62e36c819ebaff7557dc Mon Sep 17 00:00:00 2001
From: Alex Janka <alex@alexjanka.com>
Date: Sun, 23 Apr 2023 10:12:48 +1000
Subject: [PATCH] error is white (colour corrected for cgb) in release builds

---
 lib/src/processor/memory/mmio/gpu.rs           | 18 +++++++++++-------
 .../processor/memory/mmio/gpu/tile_window.rs   |  4 ++--
 lib/src/processor/memory/mmio/gpu/types.rs     | 16 ++++++++++++++--
 3 files changed, 27 insertions(+), 11 deletions(-)

diff --git a/lib/src/processor/memory/mmio/gpu.rs b/lib/src/processor/memory/mmio/gpu.rs
index 9c5fc25..189e03f 100644
--- a/lib/src/processor/memory/mmio/gpu.rs
+++ b/lib/src/processor/memory/mmio/gpu.rs
@@ -132,7 +132,7 @@ where
         } else {
             None
         };
-        let buffer = vec![ColourInner::Error.rgb_bytes(None).into(); WIDTH * HEIGHT];
+        let buffer = vec![ColourInner::Error.rgb_bytes(None, false).into(); WIDTH * HEIGHT];
 
         Self {
             buffer,
@@ -321,8 +321,9 @@ where
             *e = true;
         }
         for x in 0..WIDTH {
-            self.buffer[(scanline as usize * WIDTH) + x] =
-                ColourInner::Error.rgb_bytes(None).into();
+            self.buffer[(scanline as usize * WIDTH) + x] = ColourInner::Error
+                .rgb_bytes(None, self.is_cgb_mode())
+                .into();
         }
         if self.lcdc.bg_window_enable {
             self.render_scanline_bg(scanline);
@@ -335,8 +336,9 @@ where
             }
         } else {
             for x in 0..WIDTH {
-                self.buffer[(scanline as usize * WIDTH) + x] =
-                    ColourInner::Error.rgb_bytes(None).into();
+                self.buffer[(scanline as usize * WIDTH) + x] = ColourInner::Error
+                    .rgb_bytes(None, self.is_cgb_mode())
+                    .into();
             }
         }
         if self.lcdc.obj_enable {
@@ -487,7 +489,8 @@ where
                         )
                     });
 
-                    self.buffer[buffer_index] = colour.rgb_bytes(cgb_data).into();
+                    self.buffer[buffer_index] =
+                        colour.rgb_bytes(cgb_data, self.is_cgb_mode()).into();
                 }
             }
         }
@@ -564,7 +567,8 @@ where
                 .as_ref()
                 .map(|v| (v.palettes.bg, attributes.palette));
 
-            self.buffer[(scanline as usize * WIDTH) + x] = colour.rgb_bytes(cgb_data).into();
+            self.buffer[(scanline as usize * WIDTH) + x] =
+                colour.rgb_bytes(cgb_data, self.is_cgb_mode()).into();
         }
     }
 
diff --git a/lib/src/processor/memory/mmio/gpu/tile_window.rs b/lib/src/processor/memory/mmio/gpu/tile_window.rs
index 82c69f7..30d242a 100644
--- a/lib/src/processor/memory/mmio/gpu/tile_window.rs
+++ b/lib/src/processor/memory/mmio/gpu/tile_window.rs
@@ -27,7 +27,7 @@ where
     pub(super) fn new(window: R) -> Self {
         Self {
             sprite_buffer: vec![
-                ColourInner::Error.rgb_bytes(None).into();
+                ColourInner::Error.rgb_bytes(None, false).into();
                 TILE_WINDOW_WIDTH * TILE_WINDOW_HEIGHT
             ],
             sprite_renderer: window,
@@ -110,7 +110,7 @@ where
                     };
 
                     self.sprite_buffer[real_px_x + (real_px_y * TILE_WINDOW_WIDTH)] = colour
-                        .rgb_bytes(cgb_data.map(|v| (v, attributes.palette)))
+                        .rgb_bytes(cgb_data.map(|v| (v, attributes.palette)), is_cgb_mode)
                         .into();
                 }
             }
diff --git a/lib/src/processor/memory/mmio/gpu/types.rs b/lib/src/processor/memory/mmio/gpu/types.rs
index 559826c..39ad746 100644
--- a/lib/src/processor/memory/mmio/gpu/types.rs
+++ b/lib/src/processor/memory/mmio/gpu/types.rs
@@ -138,7 +138,11 @@ fn rgb_from_bytes(bytes: u16) -> Colour {
 }
 
 impl ColourInner {
-    pub(super) fn rgb_bytes(&self, cgb_data: Option<(CgbPalette, u8)>) -> Colour {
+    pub(super) fn rgb_bytes(
+        &self,
+        cgb_data: Option<(CgbPalette, u8)>,
+        is_cgb_mode: bool,
+    ) -> Colour {
         if let Some((cgb_palette, pallete_num)) = cgb_data {
             if *self == ColourInner::Error {
                 return Colour(0xFF, 0, 0);
@@ -152,7 +156,15 @@ impl ColourInner {
                 ColourInner::One => Colour(0xAA, 0xAA, 0xAA),
                 ColourInner::Two => Colour(0x55, 0x55, 0x55),
                 ColourInner::Three => Colour(0x00, 0x00, 0x00),
-                ColourInner::Error => Colour(0xFF, 0x00, 0x00),
+                ColourInner::Error => {
+                    if cfg!(debug_assertions) {
+                        Colour(0xFF, 0x00, 0x00)
+                    } else if is_cgb_mode {
+                        rgb_from_bytes(0xFFFF)
+                    } else {
+                        Colour(0xFF, 0xFF, 0xFF)
+                    }
+                }
             }
         }
     }