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base: paoda:06ee31980ec601ab3c56449c7f42a2df11d68652
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paoda:april-fools
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paoda:apu-things
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compare: paoda:102eb0c1e65d24a408362b62464251bfded5aee9
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paoda:main
paoda:april-fools
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paoda:apu-things

3 Commits
06ee31980e ... 102eb0c1e6

Author SHA1 Message Date
Rekai Nyangadzayi Musuka 102eb0c1e6 fix(window): proper inRange impl for window 
window wrap now works (it's pretty slow though?)
 2022-11-03 03:35:03 -03:00
Rekai Nyangadzayi Musuka dda533f557 chore: improve readability of sprite drawing code a bit 2022-11-03 03:35:03 -03:00
Rekai Nyangadzayi Musuka 29e9d3c288 style: remove unused imports 2022-11-02 09:02:17 -03:00
2 changed files with 42 additions and 58 deletions
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9
src/core/bus/io.zig
View File

@ -428,8 +428,6 @@ const u8WriteKind = enum { Hi, Lo };
/// Write-only
pub const WinH = extern union {
const Self = @This();
x2: Bitfield(u16, 0, 8),
x1: Bitfield(u16, 8, 8),
raw: u16,
@ -442,13 +440,6 @@ pub const WinV = extern union {
y2: Bitfield(u16, 0, 8),
y1: Bitfield(u16, 8, 8),
raw: u16,
pub fn set(self: *Self, comptime K: u8WriteKind, value: u8) void {
self.raw = switch (K) {
.Hi => (@as(u16, value) << 8) | self.raw & 0xFF,
.Lo => (self.raw & 0xFF00) | value,
};
}
};
pub const WinIn = extern union {

91
src/core/ppu.zig
View File

@ -9,7 +9,6 @@ const dma = @import("bus/dma.zig");
const Oam = @import("ppu/Oam.zig");
const Palette = @import("ppu/Palette.zig");
const Vram = @import("ppu/Vram.zig");
const EventKind = @import("scheduler.zig").EventKind;
const Scheduler = @import("scheduler.zig").Scheduler;
const Arm7tdmi = @import("cpu.zig").Arm7tdmi;
const FrameBuffer = @import("../util.zig").FrameBuffer;
@ -20,7 +19,6 @@ const log = std.log.scoped(.PPU);
const getHalf = util.getHalf;
const setHalf = util.setHalf;
const setQuart = util.setQuart;
const pollDmaOnBlank = @import("bus/dma.zig").pollDmaOnBlank;
pub const width = 240;
pub const height = 160;
@ -265,8 +263,7 @@ pub const Ppu = struct {
scanline: Scanline,
pub fn init(allocator: Allocator, sched: *Scheduler) !Self {
// Queue first Hblank
sched.push(.Draw, 240 * 4);
sched.push(.Draw, 240 * 4); // Add first PPU Event to Scheduler
const sprites = try allocator.create([128]?Sprite);
std.mem.set(?Sprite, sprites, null);
@ -326,20 +323,16 @@ pub const Ppu = struct {
// Only consider enabled Sprites
if (attr0.is_affine.read() or !attr0.disabled.read()) {
const attr1 = @bitCast(Attr1, self.oam.read(u16, i + 2));
const sprite_height = spriteDimensions(attr0.shape.read(), attr1.size.read())[1];
// When fetching sprites we only care about ones that could be rendered
// on this scanline
const iy = @bitCast(i8, y);
const start = attr0.y.read();
const istart = @bitCast(i8, start);
const end = start +% spriteDimensions(attr0.shape.read(), attr1.size.read())[1];
const iend = @bitCast(i8, end);
var y_pos: i32 = attr0.y.read();
if (y_pos >= 160) y_pos -= 256; // fleroviux's solution to negative positions
// Sprites are expected to be able to wraparound, we perform the same check
// for unsigned and signed values so that we handle all valid sprite positions
if ((start <= y and y < end) or (istart <= iy and iy < iend)) {
if (y_pos <= y and y < (y_pos + sprite_height)) {
for (self.scanline_sprites) |*maybe_sprite| {
if (maybe_sprite.* == null) {
maybe_sprite.* = Sprite.init(attr0, attr1, @bitCast(Attr2, self.oam.read(u16, i + 4)));
@ -366,8 +359,6 @@ pub const Ppu = struct {
}
fn drawAffineSprite(self: *Self, sprite: AffineSprite) void {
const iy = @bitCast(i8, self.vcount.scanline.read());
const is_8bpp = sprite.is8bpp();
const tile_id: u32 = sprite.tileId();
const obj_mapping = self.dispcnt.obj_mapping.read();
@ -376,25 +367,22 @@ pub const Ppu = struct {
const char_base = 0x4000 * 4;
const y = self.vcount.scanline.read();
var i: u9 = 0;
while (i < sprite.width) : (i += 1) {
const x = (sprite.x() +% i) % width;
const ix = @bitCast(i9, x);
if (!shouldDrawSprite(self.bld.cnt, &self.scanline, x)) continue;
const sprite_start = sprite.x();
const isprite_start = @bitCast(i9, sprite_start);
const sprite_end = sprite_start +% sprite.width;
const isprite_end = @bitCast(i9, sprite_end);
var x_pos: i32 = sprite.x();
if (x_pos >= 240) x_pos -= 512;
const condition = (sprite_start <= x and x < sprite_end) or (isprite_start <= ix and ix < isprite_end);
if (!condition) continue;
if (!(x_pos <= x and x < (x_pos + sprite.width))) continue;
// Sprite is within bounds and therefore should be rendered
// std.math.absInt is branchless
const tile_x = @bitCast(u9, std.math.absInt(ix - @bitCast(i9, sprite.x())) catch unreachable);
const tile_y = @bitCast(u8, std.math.absInt(iy -% @bitCast(i8, sprite.y())) catch unreachable);
const tile_x = @bitCast(u32, @as(i32, std.math.absInt(@as(i32, x) - x_pos) catch unreachable));
const tile_y = @bitCast(u32, @as(i32, std.math.absInt(@bitCast(i8, y) -% @bitCast(i8, sprite.y())) catch unreachable));
const row = @truncate(u3, tile_y);
const col = @truncate(u3, tile_x);
@ -416,8 +404,6 @@ pub const Ppu = struct {
}
fn drawSprite(self: *Self, sprite: Sprite) void {
const iy = @bitCast(i8, self.vcount.scanline.read());
const is_8bpp = sprite.is8bpp();
const tile_id: u32 = sprite.tileId();
const obj_mapping = self.dispcnt.obj_mapping.read();
@ -426,31 +412,27 @@ pub const Ppu = struct {
const char_base = 0x4000 * 4;
const y = self.vcount.scanline.read();
var i: u9 = 0;
while (i < sprite.width) : (i += 1) {
const x = (sprite.x() +% i) % width;
const ix = @bitCast(i9, x);
if (!shouldDrawSprite(self.bld.cnt, &self.scanline, x)) continue;
const sprite_start = sprite.x();
const isprite_start = @bitCast(i9, sprite_start);
const sprite_end = sprite_start +% sprite.width;
const isprite_end = @bitCast(i9, sprite_end);
var x_pos: i32 = sprite.x();
if (x_pos >= 240) x_pos -= 512;
const condition = (sprite_start <= x and x < sprite_end) or (isprite_start <= ix and ix < isprite_end);
if (!condition) continue;
if (!(x_pos <= x and x < (x_pos + sprite.width))) continue;
// Sprite is within bounds and therefore should be rendered
// std.math.absInt is branchless
const x_diff = @bitCast(u9, std.math.absInt(ix - @bitCast(i9, sprite.x())) catch unreachable);
const y_diff = @bitCast(u8, std.math.absInt(iy -% @bitCast(i8, sprite.y())) catch unreachable);
const x_diff: i32 = std.math.absInt(@as(i32, x) - x_pos) catch unreachable;
const y_diff: i32 = std.math.absInt(@bitCast(i8, y) -% @bitCast(i8, sprite.y())) catch unreachable;
// Note that we flip the tile_pos not the (tile_pos % 8) like we do for
// Background Tiles. By doing this we mirror the entire sprite instead of
// just a specific tile (see how sprite.width and sprite.height are involved)
const tile_y = y_diff ^ if (sprite.vFlip()) (sprite.height - 1) else 0;
const tile_x = x_diff ^ if (sprite.hFlip()) (sprite.width - 1) else 0;
const tile_x = @intCast(u9, x_diff) ^ if (sprite.hFlip()) (sprite.width - 1) else 0;
const tile_y = @intCast(u8, y_diff) ^ if (sprite.vFlip()) (sprite.height - 1) else 0;
const row = @truncate(u3, tile_y);
const col = @truncate(u3, tile_x);
@ -980,24 +962,35 @@ const Window = struct {
}
fn inRange(self: *const Self, comptime id: u1, x: u9, y: u8) bool {
const h = self.h[id];
const v = self.v[id];
const winh = self.h[id];
const winv = self.v[id];
const y1 = v.y1.read();
const y2 = if (y1 > v.y2.read()) 160 else std.math.min(160, v.y2.read());
if (y1 <= y and y < y2) {
// Within Y bounds
const x1 = h.x1.read();
const x2 = if (x1 > h.x2.read()) 240 else std.math.min(240, h.x2.read());
if (isYInRange(winv, y)) {
const x1 = winh.x1.read();
const x2 = winh.x2.read();
// Within X Bounds
return x1 <= x and x < x2;
return if (x1 < x2) blk: {
break :blk x >= x1 and x < x2;
} else blk: {
break :blk x >= x1 or x < x2;
};
}
return false;
}
inline fn isYInRange(winv: io.WinV, y: u9) bool {
const y1 = winv.y1.read();
const y2 = winv.y2.read();
if (y1 < y2) {
return y >= y1 and y < y2;
} else {
return y >= y1 or y < y2;
}
}
pub fn setH(self: *Self, value: u32) void {
self.h[0].raw = @truncate(u16, value);
self.h[1].raw = @truncate(u16, value >> 16);