Fix tearing

src/emulator.rs

@@ -109,9 +109,7 @@ impl Emulator {
         }
     }
 
-    pub fn run(&mut self, cpu_cycles: Cycles, frame_buffer: &mut [u8]) {
-        self.cpu.reset_cycles();
-        while self.cpu.get_cycles().to_t().0 <= cpu_cycles.0 {
+    fn tick(&mut self, frame_buffer: &mut [u8]) {
         self.cpu.run(&mut self.bus);
         let cycles = self.cpu.get_last_op_cycles().to_t();
         self.bus.ppu.do_cycles(&mut self.bus.interrupts, cycles, frame_buffer);
@@ -123,7 +121,23 @@ impl Emulator {
 
         // 1 CPU cycle = 238.42ns
         // thread::sleep(time::Duration::from_nanos((self.cpu.get_last_op_cycles().0 * 238).try_into().unwrap()));
+    }
 
+    pub fn run(&mut self, cpu_cycles: Cycles, frame_buffer: &mut [u8]) {
+        self.cpu.reset_cycles();
+        while self.cpu.get_cycles().to_t().0 <= cpu_cycles.0 {
+            self.tick(frame_buffer);
+        }
+    }
+
+    pub fn run_frame(&mut self, frame_buffer: &mut [u8]) {
+        self.cpu.reset_cycles();
+        let mut frame_started = true;
+        while self.bus.ppu.lcd_y() < 144 || frame_started {
+            self.tick(frame_buffer);
+            if self.bus.ppu.lcd_y() == 0 {
+                frame_started = false;
+            }
         }
     }
 

src/ppu.rs

@@ -345,6 +345,10 @@ impl PPU {
         }
     }
 
+    pub fn lcd_y(&self) -> u8 {
+        self.lcd_y
+    }
+
     pub fn set_vram_bank(&mut self, bank: u8) {
         if self.cgb_mode {
             self.vram_bank = bank & 1;

src/render.rs

@@ -1,6 +1,5 @@
 use crate::emulator::Emulator;
 use crate::frames::Frames;
-use crate::cpu::Cycles;
 use crate::ppu::{WIDTH, HEIGHT};
 
 use log::error;
@@ -81,7 +80,7 @@ pub fn start_eventloop() {
                 *control_flow = ControlFlow::Exit
             },
             Event::MainEventsCleared => {
-                emulator.run(Cycles(70224.0), pixels.get_frame());
+                emulator.run_frame(pixels.get_frame());
                 frame_counter.increment();
                 if frame_counter.elapsed_ms() >= 1000 {
                     window.set_title(&format!("rmg-001 (FPS: {})", frame_counter.count()));