diff --git a/examples/sdl/src/main.rs b/examples/sdl/src/main.rs
index 066517937fb454254b7d3734afcb4d590ad99a9b..846e1f28ce7571664ed6e4ab7cc601bfe40ee844 100644
--- a/examples/sdl/src/main.rs
+++ b/examples/sdl/src/main.rs
@@ -43,7 +43,10 @@ impl Emulator {
pub fn load_rom(&mut self, path: &str) {
let rom = self.system.load_rom_file(path);
- println!("==== Cartridge ====\n{}\n===================", rom);
+ println!(
+ "========= Cartridge =========\n{}\n=============================\n",
+ rom
+ );
}
pub fn run(&mut self) {
diff --git a/examples/web/index.ts b/examples/web/index.ts
index f2e4f018d27232c0e5d8d9a61889cd8809915a3f..b1a010421d4979170b91b566c668980a9aed9cea 100644
--- a/examples/web/index.ts
+++ b/examples/web/index.ts
@@ -1,4 +1,4 @@
-import { default as wasm, GameBoy, PadKey } from "./lib/boytacean.js";
+import { default as wasm, GameBoy, PadKey, PpuMode } from "./lib/boytacean.js";
import info from "./package.json";
const PIXEL_UNSET_COLOR = 0x1b1a17ff;
@@ -41,7 +41,7 @@ const KEYS: Record<string, number> = {
};
// @ts-ignore: ts(2580)
-const ROM_PATH = require("../../res/roms/firstwhite.gb");
+const ROM_PATH = require("../../res/roms/20y.gb");
// Enumeration that describes the multiple pixel
// formats and the associated byte size.
@@ -217,6 +217,8 @@ const tick = (currentTime: number) => {
let counterTicks = 0;
+ let lastFrame = -1;
+
while (true) {
// limits the number of ticks to the typical number
// of ticks required to do a complete PPU draw
@@ -227,11 +229,20 @@ const tick = (currentTime: number) => {
// runs the Game Boy clock, this operations should
// include the advance of both the CPU and the PPU
counterTicks += state.gameBoy.clock();
- }
- // updates the canvas object with the new
- // visual information coming in
- updateCanvas(state.gameBoy.frame_buffer_eager(), PixelFormat.RGB);
+ // in case the current PPU mode is VBlank and the
+ // fram is different from the previously rendered
+ // one then it's time to update the canvas
+ if (
+ state.gameBoy.ppu_mode() == PpuMode.VBlank &&
+ state.gameBoy.ppu_frame() != lastFrame
+ ) {
+ // updates the canvas object with the new
+ // visual information coming in
+ updateCanvas(state.gameBoy.frame_buffer_eager(), PixelFormat.RGB);
+ lastFrame = state.gameBoy.ppu_frame();
+ }
+ }
// increments the number of frames rendered in the current
// section, this value is going to be used to calculate FPS
@@ -544,7 +555,7 @@ const registerButtons = () => {
/**
* Draws the tile at the given index to the proper
* vertical offset in the given context and buffer.
- *
+ *
* @param index The index of the sprite to be drawn.
* @param format The pixel format of the sprite.
*/
@@ -552,7 +563,7 @@ const registerButtons = () => {
index: number,
context: CanvasRenderingContext2D,
buffer: DataView,
- format: PixelFormat = PixelFormat.RGB,
+ format: PixelFormat = PixelFormat.RGB
) => {
const pixels = state.gameBoy.get_tile_buffer(index);
const line = Math.floor(index / 16);
diff --git a/res/roms/20y.gb b/res/roms/20y.gb
new file mode 100644
index 0000000000000000000000000000000000000000..139c684a227553640090a1db0dc765384be07f61
Binary files /dev/null and b/res/roms/20y.gb differ
diff --git a/src/gb.rs b/src/gb.rs
index 954ecc3798a105c42a61d63291d1ee4dec8e6e8a..7ab861d62f79b26653aae71f579947c68c3ea11d 100644
--- a/src/gb.rs
+++ b/src/gb.rs
@@ -3,7 +3,7 @@ use crate::{
data::{BootRom, DMG_BOOT, DMG_BOOTIX, MGB_BOOTIX, SGB_BOOT},
mmu::Mmu,
pad::{Pad, PadKey},
- ppu::{Ppu, Tile, FRAME_BUFFER_SIZE},
+ ppu::{Ppu, PpuMode, Tile, FRAME_BUFFER_SIZE},
rom::Cartridge,
timer::Timer,
util::read_file,
@@ -50,6 +50,18 @@ impl GameBoy {
self.cpu.pc()
}
+ pub fn ppu_ly(&mut self) -> u8 {
+ self.ppu().ly()
+ }
+
+ pub fn ppu_mode(&mut self) -> PpuMode {
+ self.ppu().mode()
+ }
+
+ pub fn ppu_frame(&mut self) -> u16 {
+ self.ppu().frame_index()
+ }
+
pub fn clock(&mut self) -> u8 {
let cycles = self.cpu_clock();
self.ppu_clock(cycles);
diff --git a/src/ppu.rs b/src/ppu.rs
index d39e0d4963d6067bbd2bc88b8601459f90c25ac5..1b051ed176221667729f900eed3a2641e25aed7d 100644
--- a/src/ppu.rs
+++ b/src/ppu.rs
@@ -242,6 +242,11 @@ pub struct Ppu {
/// first one, preventing actions.
first_frame: bool,
+ /// Almost unique identifier of the frame that can be used to debug
+ /// and uniquely identify the frame that is currently ind drawing,
+ /// the identifier wraps on the u16 edges.
+ frame_index: u16,
+
stat_hblank: bool,
stat_vblank: bool,
stat_oam: bool,
@@ -256,6 +261,7 @@ pub struct Ppu {
int_stat: bool,
}
+#[cfg_attr(feature = "wasm", wasm_bindgen)]
#[derive(Clone, Copy, PartialEq)]
pub enum PpuMode {
HBlank = 0,
@@ -304,6 +310,7 @@ impl Ppu {
window_map: false,
switch_lcd: false,
first_frame: false,
+ frame_index: 0,
stat_hblank: false,
stat_vblank: false,
stat_oam: false,
@@ -338,6 +345,7 @@ impl Ppu {
self.window_map = false;
self.switch_lcd = false;
self.first_frame = false;
+ self.frame_index = 0;
self.stat_hblank = false;
self.stat_vblank = false;
self.stat_oam = false;
@@ -404,6 +412,7 @@ impl Ppu {
self.mode = PpuMode::OamRead;
self.ly = 0;
self.first_frame = false;
+ self.frame_index = self.frame_index.wrapping_add(1);
}
self.mode_clock -= 456;
@@ -556,6 +565,18 @@ impl Ppu {
self.palette_obj_1
}
+ pub fn ly(&self) -> u8 {
+ self.ly
+ }
+
+ pub fn mode(&self) -> PpuMode {
+ self.mode
+ }
+
+ pub fn frame_index(&self) -> u16 {
+ self.frame_index
+ }
+
pub fn int_vblank(&self) -> bool {
self.int_vblank
}