Reorganise PPU

src/components/ppu/bgpi.rs

@@ -0,0 +1,27 @@
+pub struct BGPI {
+ pub address: u8,
+ pub auto_increment: bool
+}
+
+impl BGPI {
+ pub fn new() -> Self {
+ Self {
+ address: 0,
+ auto_increment: false
+ }
+ }
+
+ pub fn read(&self) -> u8 {
+ let a = if self.auto_increment {
+ 0x80
+ } else {
+ 0x00
+ };
+ a | self.address
+ }
+
+ pub fn write(&mut self, v: u8) {
+ self.auto_increment = v & 0x80 != 0x00;
+ self.address = v & 0x3F;
+ }
+}

src/components/ppu/mod.rs

@@ -1,2 +1,4 @@
 pub mod ppu;
-mod cc;
+mod cc;
+mod bgpi;
+mod structs;

src/components/ppu/ppu.rs

@@ -1,8 +1,9 @@
 use crate::components::prelude::*;
 use crate::config::{Color, Config, Palette, PPUConfig};
 use crate::Framebuffer;
-use bitflags::bitflags;
+use crate::components::ppu::bgpi::BGPI;
 use crate::components::ppu::cc::ColorCorrection;
+use crate::components::ppu::structs::*;
 
 /// RGBA (4 bytes) per pixel
 pub const FRAMEBUFFER_SIZE: usize = 4 * SCREEN_W * SCREEN_H;
@@ -41,99 +42,6 @@ pub struct PPU {
  pub framebuffer: Framebuffer,
 }
 
-#[derive(PartialEq, Copy, Clone)]
-enum Priority {
- Color0,
- Priority,
- Normal,
-}
-
-#[derive(PartialEq, Copy, Clone)]
-enum PPUMode {
- OAMScan = 2,
- Draw = 3,
- HBlank = 0,
- VBlank = 1,
-}
-
-bitflags! {
- #[derive(PartialEq, Copy, Clone)]
- pub struct Attributes: u8 {
- const PRIORITY = 0b1000_0000;
- const Y_FLIP = 0b0100_0000;
- const X_FLIP = 0b0010_0000;
- const PALETTE_NO_0 = 0b0001_0000;
- const BANK = 0b0000_1000;
- }
-}
-
-bitflags! {
- #[derive(PartialEq, Copy, Clone)]
- pub struct LCDC: u8 {
- // LCD & PPU enable: 0 = Off; 1 = On
- const LCD_ENABLE = 0b1000_0000;
- // Window tile map area: 0 = 9800–9BFF; 1 = 9C00–9FFF
- const WINDOW_AREA = 0b0100_0000;
- // Window enable: 0 = Off; 1 = On
- const WINDOW_ENABLE = 0b0010_0000;
- // BG & Window tile data area: 0 = 8800–97FF; 1 = 8000–8FFF
- const TILE_DATA_AREA = 0b0001_0000;
- // BG tile map area: 0 = 9800–9BFF; 1 = 9C00–9FFF
- const BG_TILE_MAP_AREA = 0b0000_1000;
- // OBJ size: 0 = 8×8; 1 = 8×16
- const OBJ_SIZE = 0b0000_0100;
- // OBJ enable: 0 = Off; 1 = On
- const OBJ_ENABLE = 0b0000_0010;
- // BG & Window enable (GB) / priority (CGB): 0 = Off; 1 = On
- const WINDOW_PRIORITY = 0b0000_0001;
- }
-}
-
-bitflags! {
- #[derive(PartialEq, Copy, Clone)]
- pub struct LCDS: u8 {
- // LYC int select (Read/Write): If set, selects the LYC == LY condition for the STAT interrupt.
- const LYC_SELECT = 0b0100_0000;
- // Mode 2 int select (Read/Write): If set, selects the Mode 2 condition for the STAT interrupt.
- const MODE_2_SELECT = 0b0010_0000;
- // Mode 1 int select (Read/Write): If set, selects the Mode 1 condition for the STAT interrupt.
- const MODE_1_SELECT = 0b0001_0000;
- // Mode 0 int select (Read/Write): If set, selects the Mode 0 condition for the STAT interrupt.
- const MODE_0_SELECT = 0b0000_1000;
- // LYC == LY (Read-only): Set when LY contains the same value as LYC; it is constantly updated.
- const LYC_EQUALS = 0b0000_0100;
- // PPU mode (Read-only): Indicates the PPU’s current status.
- }
-}
-
-struct BGPI {
- address: u8,
- auto_increment: bool
-}
-
-impl BGPI {
- fn new() -> Self {
- Self {
- address: 0,
- auto_increment: false
- }
- }
-
- fn read(&self) -> u8 {
- let a = if self.auto_increment {
- 0x80
- } else {
- 0x00
- };
- a | self.address
- }
-
- fn write(&mut self, v: u8) {
- self.auto_increment = v & 0x80 != 0x00;
- self.address = v & 0x3F;
- }
-}
-
 impl PPU {
  pub fn new(config: Config, framebuffer: Framebuffer) -> Self {
  Self {
@@ -296,7 +204,22 @@ impl PPU {
  CCMode::SGB => self.cc.sgb_color_lut[color as usize],
  };
 
- self.write_pixel(color[0], color[1], color[2], x, self.ly);
+ self.set_pixel(color[0], color[1], color[2], x, self.ly);
+ }
+
+ fn set_pixel(&mut self, r: u8, g: u8, b: u8, x: usize, y: u8) {
+ pub const BYTES_PER_PIXEL: usize = 4;
+ pub const BYTES_PER_ROW: usize = BYTES_PER_PIXEL * SCREEN_W;
+
+ let vertical_offset = y as usize * BYTES_PER_ROW;
+ let horizontal_offset = x * BYTES_PER_PIXEL;
+ let total_offset = vertical_offset + horizontal_offset;
+
+ let mut framebuffer = self.framebuffer.write().unwrap();
+ framebuffer[total_offset + 0] = r;
+ framebuffer[total_offset + 1] = g;
+ framebuffer[total_offset + 2] = b;
+ framebuffer[total_offset + 3] = 0xFF;
  }
 
  fn draw_bg(&mut self) {
@@ -407,7 +330,7 @@ impl PPU {
  Self::grey_to_l(self.ppu_config.palette, self.bgp, color)
  };
 
- self.write_pixel(color.r(), color.g(), color.b(), x, self.ly);
+ self.set_pixel(color.r(), color.g(), color.b(), x, self.ly);
  }
  }
  }
@@ -516,7 +439,7 @@ impl PPU {
  Self::grey_to_l(self.ppu_config.palette, self.obp0, color)
  };
 
- self.write_pixel(color.r(), color.g(), color.b(), px.wrapping_add(x) as usize, self.ly);
+ self.set_pixel(color.r(), color.g(), color.b(), px.wrapping_add(x) as usize, self.ly);
  }
  }
  }
@@ -529,21 +452,6 @@ impl PPU {
  fn write_vram(&mut self, a: u16, v: u8, bank: usize) {
  self.vram[(bank * 0x2000) + a as usize - 0x8000] = v;
  }
-
- fn write_pixel(&mut self, r: u8, g: u8, b: u8, x: usize, y: u8) {
- pub const BYTES_PER_PIXEL: usize = 4;
- pub const BYTES_PER_ROW: usize = BYTES_PER_PIXEL * SCREEN_W;
-
- let vertical_offset = y as usize * BYTES_PER_ROW;
- let horizontal_offset = x * BYTES_PER_PIXEL;
- let total_offset = vertical_offset + horizontal_offset;
-
- let mut framebuffer = self.framebuffer.write().unwrap();
- framebuffer[total_offset + 0] = r;
- framebuffer[total_offset + 1] = g;
- framebuffer[total_offset + 2] = b;
- framebuffer[total_offset + 3] = 0xFF;
- }
 }
 
 impl Memory for PPU {
@@ -625,7 +533,7 @@ impl Memory for PPU {
 
  for y in 0..SCREEN_H {
  for x in 0..SCREEN_W {
- self.write_pixel(r, g, b, x, y as u8);
+ self.set_pixel(r, g, b, x, y as u8);
  }
  }
  },

src/components/ppu/structs.rs

@@ -0,0 +1,66 @@
+use bitflags::bitflags;
+
+#[derive(PartialEq, Copy, Clone)]
+pub enum Priority {
+ Color0,
+ Priority,
+ Normal,
+}
+
+#[derive(PartialEq, Copy, Clone)]
+pub enum PPUMode {
+ OAMScan = 2,
+ Draw = 3,
+ HBlank = 0,
+ VBlank = 1,
+}
+
+bitflags! {
+ #[derive(PartialEq, Copy, Clone)]
+ pub struct Attributes: u8 {
+ const PRIORITY = 0b1000_0000;
+ const Y_FLIP = 0b0100_0000;
+ const X_FLIP = 0b0010_0000;
+ const PALETTE_NO_0 = 0b0001_0000;
+ const BANK = 0b0000_1000;
+ }
+}
+
+bitflags! {
+ #[derive(PartialEq, Copy, Clone)]
+ pub struct LCDC: u8 {
+ // LCD & PPU enable: 0 = Off; 1 = On
+ const LCD_ENABLE = 0b1000_0000;
+ // Window tile map area: 0 = 9800–9BFF; 1 = 9C00–9FFF
+ const WINDOW_AREA = 0b0100_0000;
+ // Window enable: 0 = Off; 1 = On
+ const WINDOW_ENABLE = 0b0010_0000;
+ // BG & Window tile data area: 0 = 8800–97FF; 1 = 8000–8FFF
+ const TILE_DATA_AREA = 0b0001_0000;
+ // BG tile map area: 0 = 9800–9BFF; 1 = 9C00–9FFF
+ const BG_TILE_MAP_AREA = 0b0000_1000;
+ // OBJ size: 0 = 8×8; 1 = 8×16
+ const OBJ_SIZE = 0b0000_0100;
+ // OBJ enable: 0 = Off; 1 = On
+ const OBJ_ENABLE = 0b0000_0010;
+ // BG & Window enable (GB) / priority (CGB): 0 = Off; 1 = On
+ const WINDOW_PRIORITY = 0b0000_0001;
+ }
+}
+
+bitflags! {
+ #[derive(PartialEq, Copy, Clone)]
+ pub struct LCDS: u8 {
+ // LYC int select (Read/Write): If set, selects the LYC == LY condition for the STAT interrupt.
+ const LYC_SELECT = 0b0100_0000;
+ // Mode 2 int select (Read/Write): If set, selects the Mode 2 condition for the STAT interrupt.
+ const MODE_2_SELECT = 0b0010_0000;
+ // Mode 1 int select (Read/Write): If set, selects the Mode 1 condition for the STAT interrupt.
+ const MODE_1_SELECT = 0b0001_0000;
+ // Mode 0 int select (Read/Write): If set, selects the Mode 0 condition for the STAT interrupt.
+ const MODE_0_SELECT = 0b0000_1000;
+ // LYC == LY (Read-only): Set when LY contains the same value as LYC; it is constantly updated.
+ const LYC_EQUALS = 0b0000_0100;
+ // PPU mode (Read-only): Indicates the PPU’s current status.
+ }
+}