fix: Set BG2/3 affine parametersr to default on bios skip

Former-commit-id: e6e3016f85230af3aa495b120a3d3abb385ba463

src/core/gba.rs

@@ -78,6 +78,11 @@ impl GameBoyAdvance {
         None
     }
 
+    pub fn skip_bios(&mut self) {
+        self.cpu.skip_bios();
+        self.sysbus.io.gpu.skip_bios();
+    }
+
     fn step_cpu(&mut self, io: &mut IoDevices) -> usize {
         if io.intc.irq_pending()
             && self.cpu.last_executed.is_some()

src/core/gpu/mod.rs

@@ -248,6 +248,15 @@ impl Gpu {
         }
     }
 
+    pub fn skip_bios(&mut self) {
+        for i in 0..2 {
+            self.bg_aff[i].pa = 0x100;
+            self.bg_aff[i].pb = 0;
+            self.bg_aff[i].pc = 0;
+            self.bg_aff[i].pd = 0x100;
+        }
+    }
+
     /// helper method that reads the palette index from a base address and x + y
     pub fn read_pixel_index(&self, addr: u32, x: u32, y: u32, format: PixelFormat) -> usize {
         let ofs = addr - VRAM_ADDR;

src/plat/sdl2/main.rs

@@ -113,14 +113,8 @@ fn main() {
     let mut rom_name = Path::new(&rom_path).file_name().unwrap().to_str().unwrap();
     let cart = Cartridge::from_path(Path::new(&rom_path)).unwrap();
 
-    let mut cpu = arm7tdmi::Core::new();
-    if skip_bios {
-        cpu.skip_bios();
-    }
-    let cpu = cpu;
-
     let mut gba = GameBoyAdvance::new(
-        cpu,
+        arm7tdmi::Core::new(),
         bios_bin,
         cart,
         video.clone(),
@@ -128,6 +122,10 @@ fn main() {
         input.clone(),
     );
 
+    if skip_bios {
+        gba.skip_bios();
+    }
+
     if debug {
         #[cfg(feature = "debugger")]
         {
@@ -196,16 +194,15 @@ fn main() {
                     let bios_bin = read_bin_file(bios_path).unwrap();
 
                     // create a new emulator - TODO, export to a function
-                    let mut cpu = arm7tdmi::Core::new();
-                    cpu.skip_bios();
                     gba = GameBoyAdvance::new(
-                        cpu,
+                        arm7tdmi::Core::new(),
                         bios_bin,
                         cart,
                         video.clone(),
                         audio.clone(),
                         input.clone(),
                     );
+                    gba.skip_bios();
                 }
                 _ => {}
             }