paoda
/
turbo
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

feat(ppu): support text backdrop

This commit is contained in:
Rekai Nyangadzayi Musuka 2023-11-23 00:31:54 -06:00
parent 3a1ebfb6e6
commit e0171e5b65
1 changed files with 15 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
src/core/ppu/engine.zig
View File

@ -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();