rustyboy/src/display.rs

920 lines
31 KiB
Rust

extern crate libc;
extern crate sdl2;
use std::io::Write;
// Internal ram size
const VRAM_SIZE: usize = 0x2000;
// OAM size
const OAM_SIZE: usize = (0xFE9F - 0xFE00) + 1;
// Timing values
const TICKS_END_SCANLINE: u16 = 80;
const TICKS_END_READMODE: u16 = 172;
const TICKS_END_HBLANK: u16 = 204;
const TICKS_END_VBLANK: u16 = 456;
// Display size
const GB_PIXELS_X: usize = 160;
const GB_PIXELS_Y: usize = 144;
const SCALE: usize = 4;
const WND_RES_X: usize = GB_PIXELS_X * SCALE;
const WND_RES_Y: usize = GB_PIXELS_Y * SCALE;
// Control flags
const CTRL_LCD_DISPLAY_ENABLE: u8 = 1 << 7;
const CTRL_WND_TILE_MAP_SELECT: u8 = 1 << 6;
const CTRL_WND_DISPLAY_ENABLE: u8 = 1 << 5;
const CTRL_BG_WINDOW_TILE_DATA_SELECT: u8 = 1 << 4;
const CTRL_BG_TILE_MAP_SELECT: u8 = 1 << 3;
const CTRL_BG_SPRITE_SIZE: u8 = 1 << 2;
const CTRL_BG_SPRITE_ENABLE: u8 = 1 << 1;
const CTRL_BG_DISPLAY: u8 = 1 << 0;
// Status flags
const STAT_LYC_LC_COINCIDENCE_INT: u8 = 1 << 6;
const STAT_MODE_OAM_INT: u8 = 1 << 5;
const STAT_MODE_VBLANK_INT: u8 = 1 << 4;
const STAT_MODE_HBLANK_INT: u8 = 1 << 3;
// Sprite flags
const SPRITE_OBJ_BG_PRIORITY: u8 = 1 << 7;
const SPRITE_Y_FLIP: u8 = 1 << 6;
const SPRITE_X_FLIP: u8 = 1 << 5;
//const SPRITE_PALETTE_NO: u8 = 1 << 4; // NonCGB only
const SPRITE_TILE_VRAM_BANK: u8 = 1 << 3; // CGB only
// Display color
/*
const MONOCHROME_PALETTE: &'static [[f64; 3]; 4] = &[
[0.605, 0.734, 0.059],
[0.543, 0.672, 0.059],
[0.188, 0.383, 0.188],
[0.059, 0.219, 0.059],
];
const MONOCHROME_PALETTE: &'static [[u8; 3]; 4] = &[
[255, 255, 255],
[200, 200, 200],
[125, 125, 12],
[50, 50, 50],
];
*/
#[derive(Copy, Clone)]
struct CgbPalette([u8; 8]);
impl CgbPalette {
fn get_color(self, n: usize) -> sdl2::pixels::Color {
if n == 0 {
return sdl2::pixels::Color::RGB(255, 255, 255);
}
let v = ((self.0[2 * n + 1] as u16) << 8) | (self.0[2 * n] as u16);
let r = (v & 0b1_1111) as u8;
let g = ((v >> 5) & 0b1_1111) as u8;
let b = ((v >> 10) & 0b1_1111) as u8;
// According to some code:
// Real colors:
let r = r as u16;
let g = g as u16;
let b = b as u16;
let mapped_r = ((r * 13 + g * 2 + b) >> 1) as u8;
let mapped_g = ((g * 3 + b) << 1) as u8;
let mapped_b = ((r * 3 + g * 2 + b * 11) >> 1) as u8;
sdl2::pixels::Color::RGB(mapped_r, mapped_g, mapped_b)
}
}
struct BgMapAttributes(u8);
impl BgMapAttributes {
fn palette_number(&self) -> usize {
(self.0 & 0b111) as usize
}
fn vram_bank_number(&self) -> usize {
((self.0 >> 3) & 1) as usize
}
fn horizontal_flip(&self) -> bool {
(self.0 >> 5) != 0
}
fn vertical_flip(&self) -> bool {
(self.0 >> 6) != 0
}
}
#[derive(Debug, Copy, Clone)]
enum PixelOrigin {
Empty,
Background,
Window,
Sprite,
}
#[derive(Copy, Clone)]
struct Pixel {
origin: PixelOrigin,
color: sdl2::pixels::Color,
}
impl Default for Pixel {
fn default() -> Pixel {
Pixel {
origin: PixelOrigin::Empty,
color: sdl2::pixels::Color::RGB(255, 0, 0),
}
}
}
#[derive(Debug)]
enum DisplayMode {
ReadOAMMemory,
ReadFullMemory,
HBlank,
VBlank,
}
impl Default for DisplayMode {
fn default() -> DisplayMode {
DisplayMode::HBlank
}
}
struct Sprite {
x: u8,
y: u8,
tile: u8,
flags: u8,
}
impl Sprite {
fn is_hidden(&self) -> bool {
self.x == 0 || self.y == 0
}
fn is_foreground(&self) -> bool {
(self.flags & SPRITE_OBJ_BG_PRIORITY) == 0
}
fn is_x_flipped(&self) -> bool {
(self.flags & SPRITE_X_FLIP) == SPRITE_X_FLIP
}
fn is_y_flipped(&self) -> bool {
(self.flags & SPRITE_Y_FLIP) == SPRITE_Y_FLIP
}
fn palette(&self) -> u8 {
// GB
/*
if (self.flags & SPRITE_PALETTE_NO) == 0 {
0
} else {
1
}
*/
// GBC
self.flags & 0b111
}
// GBC only
fn vram_bank(&self) -> u8 {
if (self.flags & SPRITE_TILE_VRAM_BANK) == 0 {
0
} else {
1
}
}
}
pub struct Display {
control: u8,
status: u8,
background_palette: u8,
// Only 0 and 1 for GB
object_palette: [u8; 2],
scrollx: u8,
scrolly: u8,
windowx: u8,
windowy: u8,
curline: u8,
lyc: u8,
vram0: Box<[u8]>,
vram1: Box<[u8]>,
oam: Box<[u8]>,
vram_bank: u8,
current_ticks: u16,
current_mode: DisplayMode,
renderer: sdl2::render::Canvas<sdl2::video::Window>,
pub event_pump: sdl2::EventPump,
vblank_interrupt: bool,
stat_interrupt: bool,
pixels: [Pixel; GB_PIXELS_X * GB_PIXELS_Y],
frameskip: u8,
frame_no: u8,
// GBC:
background_palette_autoinc: bool,
background_palette_index: u8,
background_palette_cgb: [CgbPalette; 0x40 / 8],
object_palette_autoinc: bool,
object_palette_index: u8,
object_palette_cgb: [CgbPalette; 0x40 / 8],
}
impl Display {
pub fn new() -> Display {
let sdl_ctx = sdl2::init().unwrap();
let video_ctx = sdl_ctx.video().unwrap();
let wnd = video_ctx
.window("RustBoy", WND_RES_X as u32, WND_RES_Y as u32)
.position_centered()
.build()
.expect("Failed to create window :<");
let renderer = wnd.into_canvas().build().expect("Could not build renderer");
let event_pump = sdl_ctx.event_pump().expect("Getting event pump failed");
let pixels = [Pixel::default(); (GB_PIXELS_X as usize) * (GB_PIXELS_Y as usize)];
Display {
control: 0,
status: 0,
background_palette: 0,
object_palette: [0u8; 2],
scrollx: 0,
scrolly: 0,
windowx: 0,
windowy: 0,
curline: 0,
lyc: 0,
current_ticks: 0,
current_mode: DisplayMode::default(),
vram0: vec![0; VRAM_SIZE].into_boxed_slice(),
vram1: vec![0; VRAM_SIZE].into_boxed_slice(),
vram_bank: 0,
oam: vec![0; OAM_SIZE].into_boxed_slice(),
renderer,
event_pump,
vblank_interrupt: false,
stat_interrupt: false,
pixels,
frameskip: 0,
frame_no: 0,
background_palette_autoinc: false,
background_palette_index: 0,
background_palette_cgb: [CgbPalette([0u8; 2 * 4]); 0x40 / 8],
object_palette_autoinc: false,
object_palette_index: 0,
object_palette_cgb: [CgbPalette([0u8; 2 * 4]); 0x40 / 8],
}
}
fn set_pixel(&mut self, x: u8, y: u8, color: sdl2::pixels::Color, origin: PixelOrigin) {
let p = &mut self.pixels[(x as usize) + (y as usize) * GB_PIXELS_X];
p.color = color;
p.origin = origin;
}
fn get_pixel_origin(&self, x: u8, y: u8) -> PixelOrigin {
self.pixels[(x as usize) + (y as usize) * GB_PIXELS_X].origin
}
fn render_screen(&mut self) {
for y in 0..GB_PIXELS_Y {
for x in 0..GB_PIXELS_X {
let f = &mut self.pixels[(x as usize) + (y as usize) * GB_PIXELS_X];
self.renderer.set_draw_color(f.color);
self.renderer
.fill_rect(sdl2::rect::Rect::new(
x as i32 * SCALE as i32,
y as i32 * SCALE as i32,
SCALE as u32,
SCALE as u32,
))
.expect("Rendering failed");
// Clear origin after rendering
f.origin = PixelOrigin::Empty;
}
}
self.renderer
.set_draw_color(sdl2::pixels::Color::RGB(255, 0, 255));
self.renderer
.draw_rect(sdl2::rect::Rect::new(
0,
0,
(GB_PIXELS_X * SCALE) as u32,
(GB_PIXELS_Y * SCALE) as u32,
))
.expect("Rendering failed");
}
pub fn vblank_interrupt(&mut self) -> bool {
// Returns whether or not a vblank interrupt should be done
// Yes, this is polling, and yes, this sucks.
if self.vblank_interrupt {
self.vblank_interrupt = false;
true
} else {
false
}
}
pub fn stat_interrupt(&mut self) -> bool {
if self.stat_interrupt {
self.stat_interrupt = false;
true
} else {
false
}
}
pub fn write_byte(&mut self, addr: u16, val: u8) {
match addr {
0x8000..=0x9FFF => {
if (self.vram_bank & 1) == 0 {
self.vram0[(addr - 0x8000) as usize] = val
} else {
self.vram1[(addr - 0x8000) as usize] = val
}
}
0xFE00..=0xFE9F => self.oam[(addr - 0xFE00) as usize] = val,
0xFF40 => self.control = val,
0xFF41 => self.status = val,
0xFF42 => self.scrolly = val,
0xFF43 => self.scrollx = val,
0xFF44 => self.curline = 0,
0xFF45 => self.lyc = val,
// GB classic
0xFF47 => self.background_palette = val,
0xFF48 => self.object_palette[0] = val,
0xFF49 => self.object_palette[1] = val,
// GBC
0xFF68 => {
self.background_palette_index = val & 0b0111_1111;
self.background_palette_autoinc = (val >> 7) != 0;
}
0xFF69 => {
let idx = self.background_palette_index as usize;
if idx < 64 {
self.background_palette_cgb[idx / 8].0[idx % 8] = val;
} else {
panic!("OOB palette w/ autoinc");
}
if self.background_palette_autoinc {
self.background_palette_index += 1;
}
}
0xFF6A => {
self.object_palette_index = val & 0b0111_1111;
self.object_palette_autoinc = (val >> 7) != 0;
}
0xFF6B => {
let idx = self.object_palette_index as usize;
if idx < 64 {
self.object_palette_cgb[idx / 8].0[idx % 8] = val;
} else {
panic!("OOB obj palette w/ autoinc");
}
if self.object_palette_autoinc {
self.object_palette_index += 1;
}
}
0xFF4A => {
if self.windowy != val {
println!("WY set to {:02X}", val);
}
self.windowy = val;
}
0xFF4B => {
if self.windowx != val {
println!("WX set to {:02X}", val);
}
self.windowx = val;
}
0xFF4F => self.vram_bank = val,
_ => panic!("Display: Write {:02X} to {:04X} unsupported", val, addr),
}
}
pub fn read_byte(&self, addr: u16) -> u8 {
match addr {
0x8000..=0x9FFF => {
if (self.vram_bank & 1) == 0 {
self.vram0[(addr - 0x8000) as usize]
} else {
self.vram1[(addr - 0x8000) as usize]
}
}
0xFE00..=0xFE9F => self.oam[(addr - 0xFE00) as usize],
0xFF40 => self.control,
0xFF41 => self.status,
0xFF42 => self.scrolly,
0xFF43 => self.scrollx,
0xFF44 => self.curline,
0xFF45 => self.lyc,
0xFF47 => self.background_palette,
0xFF48 => self.object_palette[0],
0xFF49 => self.object_palette[1],
0xFF4A => self.windowy,
0xFF4B => self.windowx,
0xFF4F => self.vram_bank | 0b1111_1110,
_ => panic!("Display: Read from {:04X} unsupported", addr),
}
}
fn get_background_attribute(
&self,
//tile_index_x: usize,
//tile_index_y: usize,
vram_offset: usize,
) -> BgMapAttributes {
/*
let background_map = if self.control & CTRL_BG_TILE_MAP_SELECT != 0 {
0x1C00
} else {
0x1800
};
let vram_offset: usize =
background_map + ((tile_index_y as usize) * 32) + tile_index_x as usize;
*/
// Background attributes are only in this memory range.
assert!(
vram_offset >= 0x1800 && vram_offset < 0x2000,
format!("offset: {:04X}", vram_offset)
);
BgMapAttributes(self.vram1[vram_offset])
}
pub fn tick(&mut self, ticks: u16) {
self.status &= 0xFC;
if self.control & CTRL_LCD_DISPLAY_ENABLE == 0 {
// Display is disabled
self.current_ticks = 0;
self.current_mode = DisplayMode::VBlank;
self.curline = 0;
return;
}
self.current_ticks += ticks;
match self.current_mode {
DisplayMode::ReadOAMMemory => {
// Mode 2, Reading OAM memory, RAM may be accessed.
if self.current_ticks > TICKS_END_SCANLINE {
self.current_ticks = 0;
self.current_mode = DisplayMode::ReadFullMemory;
}
self.status |= 2;
}
DisplayMode::ReadFullMemory => {
// Mode 3, reading OAM, VMEM and palette data.
// Nothing may be accessed.
if self.current_ticks > TICKS_END_READMODE {
self.current_ticks = 0;
self.current_mode = DisplayMode::HBlank;
if self.frameskip < self.frame_no {
self.renderscan();
}
if self.status & STAT_MODE_HBLANK_INT > 0 {
self.stat_interrupt = true;
}
}
self.status |= 3;
}
DisplayMode::HBlank => {
// Mode 0, H-Blank, Memory (RAM, OAM) may be accessed.
if self.current_ticks > TICKS_END_HBLANK {
self.current_ticks = 0;
self.curline += 1;
// render scan?
if self.curline == 143 {
self.current_mode = DisplayMode::VBlank; // To Mode 1
if self.status & STAT_MODE_VBLANK_INT > 0 {
self.stat_interrupt = true;
}
} else {
self.current_mode = DisplayMode::ReadOAMMemory; // Mode 2 again
if self.status & STAT_MODE_OAM_INT > 0 {
self.stat_interrupt = true;
}
}
}
self.status &= 0xFC;
self.status |= 0;
}
DisplayMode::VBlank => {
// Mode 1, V-Blank (or display disabled), Memory (RAM, OAM)
// may be accessed
if self.current_ticks > TICKS_END_VBLANK {
self.current_ticks = 0;
self.curline += 1;
if self.curline == 144 {
self.vblank_interrupt = true;
}
if self.curline > 153 {
self.current_mode = DisplayMode::ReadOAMMemory; // Mode 2, scanline.
if self.frameskip < self.frame_no {
self.render_screen();
self.renderer.present();
self.renderer
.set_draw_color(sdl2::pixels::Color::RGB(255, 255, 255));
self.renderer.clear();
self.frame_no = 0;
} else {
self.frame_no += 1;
}
self.curline = 0;
if self.status & STAT_MODE_OAM_INT > 0 {
self.stat_interrupt = true;
}
}
}
self.status |= 1;
}
}
// Update the status register
if self.curline == self.lyc {
self.status |= 1 << 2;
if self.status & STAT_LYC_LC_COINCIDENCE_INT > 0 {
self.stat_interrupt = true;
}
} else {
self.status &= !(1 << 2);
}
}
fn render_sprites(&mut self, sprites: &[Sprite]) {
if self.control & CTRL_BG_SPRITE_ENABLE > 0 {
let mut num_rendered: u8 = 0;
for sprite in sprites.iter().take(39) {
// Gameboy limitation
if num_rendered >= 10 {
break;
}
// Skip hidden sprites
if sprite.is_hidden() {
continue;
}
// Calculate correct coords
let x: u8 = sprite.x.wrapping_sub(8);
// Flip sprite, TODO: What does this do in WIDE mode?
let y: u8 = sprite.y.wrapping_sub(16);
let render_y = self.curline;
// Is this sprite on the current line?
let wide_mode = self.control & CTRL_BG_SPRITE_SIZE > 0;
let actual_h = if wide_mode { 16 } else { 8 };
if sprite.is_y_flipped() {
panic!("Sorry, no y flip support yet");
}
if y.wrapping_add(actual_h) > render_y && y <= render_y {
num_rendered += 1;
let tile_offset_y: usize = render_y as usize - y as usize;
let tile_base_addr: usize = sprite.tile as usize * 16;
let tile_addr = tile_base_addr + tile_offset_y * 2;
let vram = if sprite.vram_bank() == 0 {
&*self.vram0
} else {
&*self.vram1
};
let tile_line_1 = vram[tile_addr + 0];
let tile_line_2 = vram[tile_addr + 1];
for x_o in 0..8 {
let b1: bool;
let b2: bool;
let scr_x = x.wrapping_add(x_o);
let scr_y = render_y;
let pixel_origin = self.get_pixel_origin(scr_x, scr_y);
// Do not draw if the sprite should be drawn in the background
if !sprite.is_foreground() {
match pixel_origin {
PixelOrigin::Background | PixelOrigin::Window => continue,
_ => {}
}
}
let x_maybe_flipped: u8 = if sprite.is_x_flipped() { x_o ^ 7 } else { x_o };
b1 = (tile_line_1 & 1 << (7 - x_o)) > 0;
b2 = (tile_line_2 & 1 << (7 - x_o)) > 0;
// Sprites may be transparent.
if !b1 && !b2 {
continue;
}
// GB
/*
let c = (b1 as u8) * 2 + b2 as u8;
let lookup: [u8; 4] = match sprite.palette() {
0 => [
self.object_palette[0] & 3,
(self.object_palette[0] >> 2) & 3,
(self.object_palette[0] >> 4) & 3,
(self.object_palette[0] >> 6) & 3,
],
1 => [
self.object_palette[1] & 3,
(self.object_palette[1] >> 2) & 3,
(self.object_palette[1] >> 4) & 3,
(self.object_palette[1] >> 6) & 3,
],
_ => unreachable!(),
};
let entry = MONOCHROME_PALETTE[lookup[c as usize] as usize];
// Draw stuff. We're currently only in monochrome mode
self.set_pixel(
x.wrapping_add(x_o),
render_y,
sdl2::pixels::Color::RGB(entry[0], entry[1], entry[2]),
PixelOrigin::Sprite,
);
*/
let c = ((b1 as u8) * 2 + b2 as u8) as usize;
if c == 0 {
continue;
}
let c = self.object_palette_cgb[sprite.palette() as usize].get_color(c);
self.set_pixel(
x.wrapping_add(x_maybe_flipped),
render_y,
c,
PixelOrigin::Sprite,
);
}
}
}
}
}
fn get_bg_window_tile_addr(&self, tile_id: u8) -> usize {
if (self.control & CTRL_BG_WINDOW_TILE_DATA_SELECT) == CTRL_BG_WINDOW_TILE_DATA_SELECT {
let base_addr = 0x0000;
base_addr + ((tile_id as usize) << 4)
} else {
let base_addr = 0x0800;
let tile_id = (128u8 as i8).wrapping_add(tile_id as i8) as u8;
base_addr + ((tile_id as usize) << 4)
}
}
pub fn dump_vram(&self) {
std::fs::File::create("vram0.dat")
.unwrap()
.write_all(&self.vram0)
.unwrap();
std::fs::File::create("vram1.dat")
.unwrap()
.write_all(&self.vram1)
.unwrap();
}
fn renderscan(&mut self) {
// Points to the background map offset to use.
let background_map: usize;
let window_map: usize;
// verify!
if self.control & CTRL_BG_TILE_MAP_SELECT == CTRL_BG_TILE_MAP_SELECT {
background_map = 0x1C00;
} else {
background_map = 0x1800;
}
if self.control & CTRL_WND_TILE_MAP_SELECT == CTRL_WND_TILE_MAP_SELECT {
window_map = 0x1C00;
} else {
window_map = 0x1800;
}
// Those are pixel units, not tile units.
let map_offset_y: u8 = self.scrolly;
let map_offset_x: u8 = self.scrollx;
let render_y: u8 = self.curline;
// Order sprites by priority
let mut queue: Vec<Sprite> = Vec::new();
for i in 0..39 {
queue.push(Sprite {
y: self.oam[i * 4 + 0],
x: self.oam[i * 4 + 1],
tile: self.oam[i * 4 + 2],
flags: self.oam[i * 4 + 3],
});
}
// This is the non-CGB priority.
// Smaller x coord = higher.
use std::cmp;
queue.sort_by(|x, y| {
if x.x > y.x {
cmp::Ordering::Greater
} else if x.x < y.x {
cmp::Ordering::Less
} else {
cmp::Ordering::Equal
}
});
queue.reverse();
// Render background
if (self.control & CTRL_BG_DISPLAY) == CTRL_BG_DISPLAY {
// Render pixels (20 tiles)
let render_abs_y = map_offset_y.wrapping_add(render_y);
let tile_index_y: u8 = render_abs_y >> 3;
let tile_offset_y: u8 = render_abs_y & 7;
for render_x in 0..160 {
// Absolute render coordinates
let render_abs_x = map_offset_x.wrapping_add(render_x);
let tile_index_x: u8 = render_abs_x >> 3;
let tile_offset_x: u8 = render_abs_x & 7;
let vram_offset: usize =
background_map + ((tile_index_y as usize) * 32) + tile_index_x as usize;
// Obtain tile ID in this area
let tile_id = self.vram0[vram_offset];
// GBC stuff
// Get BG map attributes
let bg_attribs = self.get_background_attribute(vram_offset);
let vram = [&*self.vram0, &*self.vram1][bg_attribs.vram_bank_number()];
// TODO: Priority
let tile_offset_y = if bg_attribs.vertical_flip() {
7 ^ tile_offset_y
} else {
tile_offset_y
};
// Obtain tile information
let tile_base_addr: usize = self.get_bg_window_tile_addr(tile_id);
// TODO: Colored background
let addr = tile_base_addr + (tile_offset_y as usize) * 2;
let tile_line_1 = vram[addr];
let tile_line_2 = vram[addr + 1];
// Get the correct bit
let b1 = if bg_attribs.horizontal_flip() {
7 ^ (1 << (7 - tile_offset_x))
} else {
1 << (7 - tile_offset_x)
};
let b2 = if bg_attribs.horizontal_flip() {
7 ^ (1 << (7 - tile_offset_x))
} else {
1 << (7 - tile_offset_x)
};
let b1: bool = (tile_line_1 & b1) != 0;
let b2: bool = (tile_line_2 & b2) != 0;
// Lookup the color
let c = ((b1 as u8) * 2 + b2 as u8) as usize;
let origin = match c {
0 => PixelOrigin::Empty, // Hack so that objects will be in front of it.
_ => PixelOrigin::Background,
};
let c = self.background_palette_cgb[bg_attribs.palette_number()].get_color(c);
self.set_pixel(render_x, render_y, c, origin);
/*
let c = (b1 as u8) * 2 + b2 as u8;
let lookup: [u8; 4] = [
self.background_palette & 3,
(self.background_palette >> 2) & 3,
(self.background_palette >> 4) & 3,
(self.background_palette >> 6) & 3,
];
let entry = MONOCHROME_PALETTE[lookup[c as usize] as usize];
let origin = match c {
0 => PixelOrigin::Empty, // Hack so that objects will be in front of it.
_ => PixelOrigin::Background,
};
self.set_pixel(
render_x,
render_y,
sdl2::pixels::Color::RGB(entry[0], entry[1], entry[2]),
origin,
);
*/
}
}
if (self.control & CTRL_WND_DISPLAY_ENABLE) == CTRL_WND_DISPLAY_ENABLE {
// Draw 'window' over the background.
// Screen coordinates of the top left corner are WX-7, WY
if self.windowx < 167 && self.windowy < 144 {
//let rx = self.windowx.wrapping_add(7);
let rx = 7u8.wrapping_sub(self.windowx);
let ry = render_y.wrapping_add(self.windowy);
for r_x in 0..160u8 {
let render_x = r_x.wrapping_add(rx);
// Absolute render coordinates
let tile_index_x: u8 = render_x >> 3;
let tile_index_y: u8 = ry >> 3;
let tile_offset_x: u8 = render_x & 7;
let tile_offset_y: u8 = ry & 7;
let vram_offset: usize =
window_map + (tile_index_y as usize) * 32 + tile_index_x as usize;
// Obtain tile ID in this area
let tile_id = self.vram0[vram_offset];
let bg_attribs = self.get_background_attribute(
//tile_index_x as usize, tile_index_y as usize
vram_offset,
);
// Get BG map attributes
let vram = if bg_attribs.vram_bank_number() == 0 {
&*self.vram0
} else {
&*self.vram1
};
// TODO: Priority
let tile_offset_x = if bg_attribs.vertical_flip() {
7 ^ tile_offset_x
} else {
tile_offset_x
};
let tile_offset_y = if bg_attribs.horizontal_flip() {
7 ^ tile_offset_y
} else {
tile_offset_y
};
// Obtain tile information
let tile_base_addr: usize = self.get_bg_window_tile_addr(tile_id);
let tile_addr = tile_base_addr + (tile_offset_y as usize) * 2;
let tile_line_1 = vram[tile_addr];
let tile_line_2 = vram[tile_addr + 1];
// Get the correct bit
let b1: bool = (tile_line_1 & 1 << (7 - tile_offset_x)) > 0;
let b2: bool = (tile_line_2 & 1 << (7 - tile_offset_x)) > 0;
let c = (b1 as u8) * 2 + b2 as u8;
let origin = match c {
0 => PixelOrigin::Empty, // Hack so that objects will be in front of it.
_ => PixelOrigin::Window,
};
let c = self.background_palette_cgb[bg_attribs.palette_number()]
.get_color(c as usize);
self.set_pixel(render_x, render_y, c, origin);
/*
let lookup: [u8; 4] = [
self.background_palette & 3,
(self.background_palette >> 2) & 3,
(self.background_palette >> 4) & 3,
(self.background_palette >> 6) & 3,
];
let entry = MONOCHROME_PALETTE[lookup[c as usize] as usize];
// Draw stuff. We're currently only in monochrome mode
let origin = match c {
0 => PixelOrigin::Empty, // Hack so that objects will be in front of it.
_ => PixelOrigin::Window,
};
self.set_pixel(
render_x,
render_y,
sdl2::pixels::Color::RGB(entry[0], entry[1], entry[2]),
origin,
);
*/
}
}
}
if (self.control & CTRL_BG_SPRITE_ENABLE) == CTRL_BG_SPRITE_ENABLE {
self.render_sprites(&queue);
}
}
}