cgb priority works almost 100%

lib/src/processor/memory/mmio/gpu.rs

@@ -11,10 +11,7 @@ use self::{
 };
 use crate::{
     connect::Renderer,
-    processor::{
-        memory::addresses::{OamAddress, VramAddress},
-        SplitRegister,
-    },
+    processor::memory::addresses::{OamAddress, VramAddress},
     util::{clear_bit, get_bit},
     HEIGHT, WIDTH,
 };
@@ -39,6 +36,7 @@ where
     pub oam: Oam,
     pub window: R,
     is_bg_zero: Vec<bool>,
+    is_bg_priority: Vec<bool>,
     lcdc: Lcdc,
     stat: Stat,
     mode_clock: usize,
@@ -68,6 +66,7 @@ where
     vram: Vram,
     oam: Oam,
     is_bg_zero: Vec<bool>,
+    is_bg_priority: Vec<bool>,
     lcdc: Lcdc,
     stat: Stat,
     mode_clock: usize,
@@ -99,6 +98,7 @@ where
             vram: gpu.vram.clone(),
             oam: gpu.oam,
             is_bg_zero: gpu.is_bg_zero.clone(),
+            is_bg_priority: gpu.is_bg_priority.clone(),
             lcdc: gpu.lcdc,
             stat: gpu.stat,
             mode_clock: gpu.mode_clock,
@@ -140,6 +140,7 @@ where
             oam: Oam::default(),
             window,
             is_bg_zero: vec![true; WIDTH],
+            is_bg_priority: vec![false; WIDTH],
             lcdc: Lcdc::default(),
             stat: Stat::default(),
             mode_clock: 0,
@@ -178,6 +179,7 @@ where
             oam: state.oam,
             window,
             is_bg_zero: state.is_bg_zero,
+            is_bg_priority: state.is_bg_priority,
             lcdc: state.lcdc,
             stat: state.stat,
             mode_clock: state.mode_clock,
@@ -320,7 +322,7 @@ where
         for e in &mut self.is_bg_zero {
             *e = true;
         }
-        if self.lcdc.bg_window_enable {
+        if self.lcdc.bg_window_enable || self.is_cgb_mode() {
             self.render_scanline_bg(scanline);
             if self.lcdc.window_enable {
                 if !self.has_window_been_enabled {
@@ -337,7 +339,7 @@ where
             }
         }
         if self.lcdc.obj_enable {
-            self.render_scanline_obj(scanline);
+            self.render_scanline_obj(scanline, !self.lcdc.bg_window_enable && self.is_cgb_mode());
         }
     }
 
@@ -369,10 +371,10 @@ where
         }
     }
 
-    fn render_scanline_obj(&mut self, scanline: u8) {
+    fn render_scanline_obj(&mut self, scanline: u8, obj_priority: bool) {
         let objs = self.parse_oam(scanline);
         for object in objs {
-            self.render_object(scanline, object);
+            self.render_object(scanline, object, obj_priority);
         }
     }
 
@@ -413,22 +415,21 @@ where
                     },
                     oam_location: (i - 0xFE00) as u8,
                 });
-                if objs.len() >= 10 {
-                    break;
-                }
             }
         }
         objs.sort_by_key(|o| {
-            let mut v: u16 = 0x0;
-            v.set_high(o.x);
-            v.set_low(o.oam_location);
-            v
+            if self.is_cgb_mode() {
+                o.oam_location
+            } else {
+                o.x
+            }
         });
+        objs.truncate(10);
         objs.reverse();
         objs
     }
 
-    fn render_object(&mut self, scanline: u8, object: Object) {
+    fn render_object(&mut self, scanline: u8, object: Object, obj_priority: bool) {
         let mut object_row = scanline.wrapping_sub(object.y.wrapping_sub(16));
         if object.flags.y_flip {
             object_row = self.lcdc.obj_size.get_height() - (object_row + 1);
@@ -471,7 +472,11 @@ where
             let x_coord = x_coord_uncorrected - 8;
             if x_coord < WIDTH {
                 let buffer_index = (scanline as usize * WIDTH) + x_coord;
-                if !object.flags.behind_bg_and_window || self.is_bg_zero[x_coord] {
+                if (!object.flags.behind_bg_and_window && !self.is_bg_priority[x_coord])
+                    || self.is_bg_zero[x_coord]
+                    || (self.is_cgb_mode() && !self.lcdc.bg_window_enable)
+                    || obj_priority
+                {
                     let cgb_data = self.cgb_data.as_ref().map(|v| {
                         (
                             v.palettes.obj,
@@ -555,6 +560,7 @@ where
                 self.bg_palette.map_bits(lsb, msb)
             };
             self.is_bg_zero[x] = is_zero;
+            self.is_bg_priority[x] = attributes.bg_priority;
 
             let cgb_data = self
                 .cgb_data

lib/src/processor/memory/mmio/gpu/cgb.rs

@@ -25,7 +25,7 @@ impl Default for CgbData {
     }
 }
 
-#[derive(Serialize, Deserialize, Clone, Copy)]
+#[derive(Serialize, Deserialize, Clone, Copy, PartialEq)]
 pub(super) enum ObjectPriorityMode {
     OamLocation = 0,
     Coordinate = 1,