diff --git a/src/core/ppu/engine.zig b/src/core/ppu/engine.zig index 053598c..08d2908 100644 --- a/src/core/ppu/engine.zig +++ b/src/core/ppu/engine.zig @@ -73,13 +73,10 @@ fn Engine(comptime kind: EngineKind) type { // TODO: Draw Sprites inline for (0..4) |i| { - if (layer == self.bg[i].cnt.priority.read() and (bg_enable >> i) & 1 == 1) - self.drawBackground(i, bus); + if (layer == self.bg[i].cnt.priority.read() and (bg_enable >> i) & 1 == 1) self.drawBackground(i, bus); } } - // TODO: IN ZBA we calculate the base address of the emu framebuffer to pass in - const buf = switch (kind) { .a => if (bus.ppu.io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back), .b => if (bus.ppu.io.powcnt.display_swap.read()) fb.btm(.back) else fb.top(.back), @@ -90,7 +87,7 @@ fn Engine(comptime kind: EngineKind) type { break :blk rgba_ptr[width * scanline ..][0..width]; }; - self.renderTextMode(scanline_buf); + self.renderTextMode(bus.dbgRead(u16, 0x0500_0000), scanline_buf); }, else => |mode| { log.err("TODO: Implement Mode {}", .{mode}); @@ -151,17 +148,17 @@ fn Engine(comptime kind: EngineKind) type { const vofs: u32 = self.bg[layer].vofs.offset.read(); const hofs: u32 = self.bg[layer].hofs.offset.read(); - const y = vofs + bus.ppu.io.nds9.vcount.scanline.read(); + const y: u32 = vofs + bus.ppu.io.nds9.vcount.scanline.read(); - for (0..width) |_i| { - const i: u32 = @intCast(_i); + for (0..width) |idx| { + const i: u32 = @intCast(idx); const x = hofs + i; // TODO: Windowing // Grab the Screen Entry from VRAM - const entry_addr = 0x0600_0000 + screen_base + tilemapOffset(size, x, y); - const entry: bg.Screen.Entry = @bitCast(bus.read(u16, entry_addr)); + const entry_addr = screen_base + tilemapOffset(size, x, y); + const entry: bg.Screen.Entry = @bitCast(bus.read(u16, 0x0600_0000 + entry_addr)); // Calculate the Address of the Tile in the designated Charblock // We also take this opportunity to flip tiles if necessary @@ -178,9 +175,11 @@ fn Engine(comptime kind: EngineKind) type { // If we're in 8bpp, then the tile value is an index into the palette, // If we're in 4bpp, we have to account for a pal bank value in the Screen entry // and then we can index the palette - const pal_id: u16 = if (!is_8bpp) get4bppTilePalette(entry.pal_bank.read(), col, tile) else tile; + const pal_addr: u32 = if (!is_8bpp) get4bppTilePalette(entry.pal_bank.read(), col, tile) else tile; - if (pal_id != 0) self.drawBackgroundPixel(layer, i, bus.read(u16, @as(u32, 0x0500_0000) + pal_id * 2)); + if (pal_addr != 0) { + self.drawBackgroundPixel(layer, i, bus.read(u16, 0x0500_0000 + pal_addr * 2)); + } } } @@ -191,17 +190,16 @@ fn Engine(comptime kind: EngineKind) type { return (@as(u8, pal_bank) << 4) | nybble_tile; } - fn renderTextMode(self: *@This(), frame_buf: []u32) void { - for (self.scanline.top(), 0..) |maybe_top, i| { - const maybe_btm = self.scanline.btm()[i]; + fn renderTextMode(self: *@This(), backdrop: u16, frame_buf: []u32) void { + for (self.scanline.top(), self.scanline.btm(), frame_buf) |maybe_top, maybe_btm, *rgba| { _ = maybe_btm; const bgr555 = switch (maybe_top) { .set => |px| px, - else => 0xAAAA, + else => backdrop, }; - frame_buf[i] = rgba888(bgr555); + rgba.* = rgba888(bgr555); } self.scanline.reset();