chore: implement a non-working mode 0
This commit is contained in:
parent
64b1bdbe19
commit
16233f3cd8
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@ -110,7 +110,7 @@ fn _write(self: *@This(), comptime T: type, comptime mode: Mode, address: u32, v
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0b00 => writeInt(T, self.wram[aligned_addr & 0x0000_FFFF ..][0..byte_count], value),
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else => self.shr_wram.write(T, .nds7, aligned_addr, value),
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},
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0x0380_0000...0x0380_FFFF => writeInt(T, self.wram[aligned_addr & 0x0000_FFFF ..][0..byte_count], value),
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0x0380_0000...0x03FF_FFFF => writeInt(T, self.wram[aligned_addr & 0x0000_FFFF ..][0..byte_count], value),
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0x0400_0000...0x04FF_FFFF => io.write(self, T, aligned_addr, value),
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0x0600_0000...0x06FF_FFFF => self.vram.write(T, .nds7, aligned_addr, value),
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>8})", .{ T, address, value }),
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@ -63,7 +63,7 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) T {
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0x0400_0214 => bus.io.irq.raw,
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0x0410_0000 => bus.io.shr.ipc.recv(.nds7),
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else => warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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else => 0, // warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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},
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u16 => switch (address) {
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0x0400_0004 => bus.io.ppu.?.nds7.dispstat.raw,
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@ -76,7 +76,7 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) T {
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0x0400_0130 => bus.io.shr.keyinput.load(.Monotonic),
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0x0400_0180 => @truncate(bus.io.shr.ipc._nds7.sync.raw),
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0x0400_0184 => @truncate(bus.io.shr.ipc._nds7.cnt.raw),
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else => warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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else => 0, // warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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},
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u8 => switch (address) {
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// DMA Transfers
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@ -89,7 +89,7 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) T {
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0x0400_0241 => bus.io.shr.wramcnt.raw,
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0x0400_0300 => @intFromEnum(bus.io.postflg),
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else => warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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else => 0, // warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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},
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else => @compileError(T ++ " is an unsupported bus read type"),
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};
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@ -110,7 +110,7 @@ pub fn write(bus: *Bus, comptime T: type, address: u32, value: T) void {
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0x0400_0214 => bus.io.irq.raw &= ~value,
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0x0400_0188 => bus.io.shr.ipc.send(.nds7, value),
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>8})", .{ T, address, value }),
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else => {}, // log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>8})", .{ T, address, value }),
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},
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u16 => switch (address) {
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// DMA Transfers
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@ -123,7 +123,7 @@ pub fn write(bus: *Bus, comptime T: type, address: u32, value: T) void {
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0x0400_0184 => bus.io.shr.ipc.setIpcFifoCnt(.nds7, value),
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0x0400_0208 => bus.io.ime = value & 1 == 1,
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>4})", .{ T, address, value }),
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else => {}, // log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>4})", .{ T, address, value }),
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},
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u8 => switch (address) {
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// DMA Transfers
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@ -133,7 +133,16 @@ pub fn write(bus: *Bus, comptime T: type, address: u32, value: T) void {
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0x0400_0100...0x0400_010F => log.warn("TODO: impl timer", .{}),
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0x0400_0208 => bus.io.ime = value & 1 == 1,
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>2})", .{ T, address, value }),
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0x0400_0301 => switch ((value >> 6) & 0b11) {
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0b00 => bus.io.haltcnt = .execute,
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0b10 => bus.io.haltcnt = .halt,
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else => |val| {
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const tag: Haltcnt = @enumFromInt(val);
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log.err("TODO: Implement {}", .{tag});
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},
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},
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else => {}, // log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>2})", .{ T, address, value }),
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},
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else => @compileError(T ++ " is an unsupported bus write type"),
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}
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@ -18,6 +18,7 @@ const log = std.log.scoped(.nds9_bus);
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main: *[4 * MiB]u8,
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wram: *Wram,
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makeshift_palram: *[2 * KiB]u8,
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scheduler: *Scheduler,
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io: io.Io,
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@ -31,6 +32,7 @@ pub fn init(allocator: Allocator, scheduler: *Scheduler, ctx: SharedCtx) !@This(
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return .{
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.main = ctx.main,
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.wram = ctx.wram,
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.makeshift_palram = try allocator.create([2 * KiB]u8),
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.ppu = try Ppu.init(allocator, ctx.vram),
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.scheduler = scheduler,
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.io = io.Io.init(ctx.io),
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@ -42,6 +44,8 @@ pub fn init(allocator: Allocator, scheduler: *Scheduler, ctx: SharedCtx) !@This(
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pub fn deinit(self: *@This(), allocator: Allocator) void {
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self.ppu.deinit(allocator);
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self.bios.deinit(allocator);
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allocator.destroy(self.makeshift_palram);
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}
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pub fn reset(_: *@This()) void {
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@ -72,6 +76,7 @@ fn _read(self: *@This(), comptime T: type, comptime mode: Mode, address: u32) T
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0x0200_0000...0x02FF_FFFF => readInt(T, self.main[aligned_addr & 0x003F_FFFF ..][0..byte_count]),
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0x0300_0000...0x03FF_FFFF => self.wram.read(T, .nds9, aligned_addr),
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0x0400_0000...0x04FF_FFFF => io.read(self, T, aligned_addr),
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0x0500_0000...0x05FF_FFFF => readInt(T, self.makeshift_palram[aligned_addr & (2 * KiB - 1) ..][0..@sizeOf(T)]),
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0x0600_0000...0x06FF_FFFF => self.ppu.vram.read(T, .nds9, aligned_addr),
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0xFFFF_0000...0xFFFF_FFFF => self.bios.read(T, address),
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else => warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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@ -102,6 +107,7 @@ fn _write(self: *@This(), comptime T: type, comptime mode: Mode, address: u32, v
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0x0200_0000...0x02FF_FFFF => writeInt(T, self.main[aligned_addr & 0x003F_FFFF ..][0..byte_count], value),
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0x0300_0000...0x03FF_FFFF => self.wram.write(T, .nds9, aligned_addr, value),
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0x0400_0000...0x04FF_FFFF => io.write(self, T, aligned_addr, value),
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0x0500_0000...0x05FF_FFFF => writeInt(T, self.makeshift_palram[aligned_addr & (2 * KiB - 1) ..][0..@sizeOf(T)], value),
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0x0600_0000...0x06FF_FFFF => self.ppu.vram.write(T, .nds9, aligned_addr, value),
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0xFFFF_0000...0xFFFF_FFFF => self.bios.write(T, address, value),
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>8})", .{ T, address, value }),
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@ -62,6 +62,8 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) T {
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0x0400_02A8, 0x0400_02AC => @truncate(bus.io.div.remainder >> shift(u64, address)),
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0x0400_02B4 => @truncate(bus.io.sqrt.result),
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0x0400_1000 => bus.ppu.engines[1].dispcnt.raw,
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0x0410_0000 => bus.io.shr.ipc.recv(.nds9),
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0x0400_4000, 0x0400_4008 => 0x0000_0000, // Lets software know this is NOT a DSi
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@ -84,6 +86,20 @@ pub fn read(bus: *const Bus, comptime T: type, address: u32) T {
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0x0400_0280 => @truncate(bus.io.div.cnt.raw),
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0x0400_02B0 => @truncate(bus.io.sqrt.cnt.raw),
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0x0400_1008 => bus.ppu.engines[1].bg[0].cnt.raw,
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0x0400_100A => bus.ppu.engines[1].bg[1].cnt.raw,
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0x0400_100C => bus.ppu.engines[1].bg[2].cnt.raw,
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0x0400_100E => bus.ppu.engines[1].bg[3].cnt.raw,
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0x0400_1010 => bus.ppu.engines[1].bg[0].hofs.raw,
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0x0400_1012 => bus.ppu.engines[1].bg[0].vofs.raw,
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0x0400_1014 => bus.ppu.engines[1].bg[1].hofs.raw,
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0x0400_1016 => bus.ppu.engines[1].bg[1].vofs.raw,
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0x0400_1018 => bus.ppu.engines[1].bg[2].hofs.raw,
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0x0400_101A => bus.ppu.engines[1].bg[2].vofs.raw,
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0x0400_101C => bus.ppu.engines[1].bg[3].hofs.raw,
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0x0400_101E => bus.ppu.engines[1].bg[3].vofs.raw,
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else => warn("unexpected: read(T: {}, addr: 0x{X:0>8}) {} ", .{ T, address, T }),
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},
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u8 => switch (address) {
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@ -108,6 +124,7 @@ const subset = @import("../../util.zig").subset;
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pub fn write(bus: *Bus, comptime T: type, address: u32, value: T) void {
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switch (T) {
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u32 => switch (address) {
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// DMA Transfers
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0x0400_00B0...0x0400_00DC => log.warn("TODO: impl DMA", .{}),
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0x0400_00E0...0x0400_00EC => log.warn("TODO: impl DMA fill", .{}),
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@ -179,6 +196,20 @@ pub fn write(bus: *Bus, comptime T: type, address: u32, value: T) void {
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0x0400_0304 => bus.ppu.io.powcnt.raw = value,
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0x0400_1008 => bus.ppu.engines[1].bg[0].cnt.raw = value,
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0x0400_100A => bus.ppu.engines[1].bg[1].cnt.raw = value,
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0x0400_100C => bus.ppu.engines[1].bg[2].cnt.raw = value,
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0x0400_100E => bus.ppu.engines[1].bg[3].cnt.raw = value,
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0x0400_1010 => bus.ppu.engines[1].bg[0].hofs.raw = value,
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0x0400_1012 => bus.ppu.engines[1].bg[0].vofs.raw = value,
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0x0400_1014 => bus.ppu.engines[1].bg[1].hofs.raw = value,
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0x0400_1016 => bus.ppu.engines[1].bg[1].vofs.raw = value,
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0x0400_1018 => bus.ppu.engines[1].bg[2].hofs.raw = value,
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0x0400_101A => bus.ppu.engines[1].bg[2].vofs.raw = value,
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0x0400_101C => bus.ppu.engines[1].bg[3].hofs.raw = value,
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0x0400_101E => bus.ppu.engines[1].bg[3].vofs.raw = value,
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else => log.warn("unexpected: write(T: {}, addr: 0x{X:0>8}, value: 0x{X:0>4})", .{ T, address, value }),
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},
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u8 => switch (address) {
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@ -400,7 +431,7 @@ pub const DispcntA = extern union {
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tile_obj_1d_boundary: Bitfield(u32, 20, 2),
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bitmap_obj_1d_boundary: Bit(u32, 22),
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obj_during_hblank: Bit(u32, 23),
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character_base: Bitfield(u32, 24, 3),
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char_base: Bitfield(u32, 24, 3),
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screen_base: Bitfield(u32, 27, 3),
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bg_ext_pal_enable: Bit(u32, 30),
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obj_ext_pal_enable: Bit(u32, 31),
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@ -476,3 +507,23 @@ pub const Dispstat = extern union {
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lyc: Bitfield(u16, 7, 9),
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raw: u16,
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};
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pub const Bgcnt = extern union {
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priority: Bitfield(u16, 0, 2),
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char_base: Bitfield(u16, 2, 4),
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mosaic_enable: Bit(u16, 6),
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colour_mode: Bit(u16, 7),
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screen_base: Bitfield(u16, 8, 5),
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display_overflow: Bit(u16, 13),
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size: Bitfield(u16, 14, 2),
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raw: u16,
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};
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/// Write Only
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const BackgroundOffset = extern union {
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offset: Bitfield(u16, 0, 9),
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raw: u16,
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};
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pub const Hofs = BackgroundOffset;
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pub const Vofs = BackgroundOffset;
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@ -21,7 +21,7 @@ pub const Ppu = struct {
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vram: *Vram,
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engines: struct { EngineA, EngineB } = .{ .{}, .{} },
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engines: struct { EngineA, EngineB },
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io: Io = .{},
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@ -44,20 +44,22 @@ pub const Ppu = struct {
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pub fn init(allocator: Allocator, vram: *Vram) !@This() {
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return .{
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.fb = try FrameBuffer.init(allocator),
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.engines = .{ try EngineA.init(allocator), try EngineB.init(allocator) },
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.vram = vram,
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};
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}
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pub fn deinit(self: @This(), allocator: Allocator) void {
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self.fb.deinit(allocator);
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inline for (self.engines) |eng| eng.deinit(allocator);
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}
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pub fn drawScanline(self: *@This(), bus: *System.Bus9) void {
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if (self.io.powcnt.engine2d_a.read())
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self.engines[0].drawScanline(bus, &self.fb, &self.io);
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self.engines[0].drawScanline(bus, &self.fb);
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if (self.io.powcnt.engine2d_b.read())
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self.engines[1].drawScanline(bus, &self.fb, &self.io);
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self.engines[1].drawScanline(bus, &self.fb);
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}
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/// HDraw -> HBlank
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@ -11,14 +11,15 @@ const Ppu = @import("../ppu.zig").Ppu;
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const width = @import("../ppu.zig").screen_width;
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const height = @import("../ppu.zig").screen_height;
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const KiB = 0x400;
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const EngineKind = enum { a, b };
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pub const EngineA = Engine(.a);
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pub const EngineB = Engine(.b);
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fn Engine(comptime kind: EngineKind) type {
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const log = std.log.scoped(.engine2d);
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_ = log; // TODO: specify between 2D-A and 2D-B
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const log = std.log.scoped(.engine2d); // TODO: specify between 2D-A and 2D-B
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// FIXME: don't commit zig crimes
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const Type = struct {
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@ -30,25 +31,79 @@ fn Engine(comptime kind: EngineKind) type {
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return struct {
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dispcnt: Type(DispcntA, DispcntB) = .{ .raw = 0x0000_0000 },
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pub fn drawScanline(self: *@This(), bus: *Bus, fb: *FrameBuffer, io: *Ppu.Io) void {
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bg: [4]bg.Text = .{ .{}, .{}, .{}, .{} },
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// TODO: Rename
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scanline: Scanline,
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pub fn init(allocator: std.mem.Allocator) !@This() {
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return .{
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.scanline = try Scanline.init(allocator),
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};
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}
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pub fn deinit(self: @This(), allocator: std.mem.Allocator) void {
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self.scanline.deinit(allocator);
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}
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pub fn drawScanline(self: *@This(), bus: *Bus, fb: *FrameBuffer) void {
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const disp_mode = self.dispcnt.display_mode.read();
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switch (disp_mode) {
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0 => { // Display Off
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const buf = switch (kind) {
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.a => if (io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back),
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.b => if (io.powcnt.display_swap.read()) fb.btm(.back) else fb.top(.back),
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.a => if (bus.ppu.io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back),
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.b => if (bus.ppu.io.powcnt.display_swap.read()) fb.btm(.back) else fb.top(.back),
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};
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@memset(buf, 0xFF); // set everything to white
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},
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1 => @panic("TODO: standard graphics display (text mode, etc)"),
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1 => {
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const bg_mode = self.dispcnt.bg_mode.read();
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const bg_enable = self.dispcnt.bg_enable.read();
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const scanline: u32 = bus.ppu.io.nds9.vcount.scanline.read();
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switch (bg_mode) {
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// BG0 BG1 BG2 BG3
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// Text/3D Text Text Text
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0 => {
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// TODO: Fetch Sprites
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for (0..4) |layer| {
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// TODO: Draw Sprites
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inline for (0..4) |i| {
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if (layer == self.bg[i].cnt.priority.read() and (bg_enable >> i) & 1 == 1)
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self.drawBackground(i, bus);
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}
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}
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// TODO: IN ZBA we calculate the base address of the emu framebuffer to pass in
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const buf = switch (kind) {
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.a => if (bus.ppu.io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back),
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.b => if (bus.ppu.io.powcnt.display_swap.read()) fb.btm(.back) else fb.top(.back),
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};
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const scanline_buf = blk: {
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const rgba_ptr: *[width * height]u32 = @ptrCast(@alignCast(buf));
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break :blk rgba_ptr[width * scanline ..][0..width];
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};
|
||||
|
||||
self.renderTextMode(scanline_buf);
|
||||
},
|
||||
else => |mode| {
|
||||
log.err("TODO: Implement Mode {}", .{mode});
|
||||
@panic("fatal error");
|
||||
},
|
||||
}
|
||||
},
|
||||
2 => { // VRAM display
|
||||
if (kind == .b) return;
|
||||
// TODO: Master Brightness can still affect this mode
|
||||
|
||||
const scanline: u32 = io.nds9.vcount.scanline.read();
|
||||
const buf = if (io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back);
|
||||
const scanline: u32 = bus.ppu.io.nds9.vcount.scanline.read();
|
||||
const buf = if (bus.ppu.io.powcnt.display_swap.read()) fb.top(.back) else fb.btm(.back);
|
||||
|
||||
const scanline_buf = blk: {
|
||||
const rgba_ptr: *[width * height]u32 = @ptrCast(@alignCast(buf));
|
||||
|
|
@ -69,9 +124,210 @@ fn Engine(comptime kind: EngineKind) type {
|
|||
},
|
||||
}
|
||||
}
|
||||
|
||||
fn drawBackground(self: *@This(), comptime layer: u2, bus: *Bus) void {
|
||||
const screen_base = blk: {
|
||||
const bgcnt_off: u32 = self.bg[layer].cnt.screen_base.read();
|
||||
const dispcnt_off: u32 = if (kind == .a) self.dispcnt.screen_base.read() else 0;
|
||||
|
||||
break :blk (2 * KiB) * bgcnt_off + (64 * KiB) * dispcnt_off;
|
||||
};
|
||||
|
||||
const char_base = blk: {
|
||||
const bgcnt_off: u32 = self.bg[layer].cnt.char_base.read();
|
||||
const dispcnt_off: u32 = if (kind == .a) self.dispcnt.char_base.read() else 0;
|
||||
|
||||
break :blk (16 * KiB) * bgcnt_off + (64 * KiB) * dispcnt_off;
|
||||
};
|
||||
|
||||
const is_8bpp = self.bg[layer].cnt.colour_mode.read();
|
||||
const size = self.bg[layer].cnt.size.read();
|
||||
|
||||
// In 4bpp: 1 byte represents two pixels so the length is (8 x 8) / 2
|
||||
// In 8bpp: 1 byte represents one pixel so the length is 8 x 8
|
||||
const tile_len: u32 = if (is_8bpp) 0x40 else 0x20;
|
||||
const tile_row_offset: u32 = if (is_8bpp) 0x8 else 0x4;
|
||||
|
||||
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();
|
||||
|
||||
for (0..width) |_i| {
|
||||
const i: u32 = @intCast(_i);
|
||||
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));
|
||||
|
||||
// Calculate the Address of the Tile in the designated Charblock
|
||||
// We also take this opportunity to flip tiles if necessary
|
||||
const tile_id: u32 = entry.tile_id.read();
|
||||
|
||||
// Calculate row and column offsets. Understand that
|
||||
// `tile_len`, `tile_row_offset` and `col` are subject to different
|
||||
// values depending on whether we are in 4bpp or 8bpp mode.
|
||||
const row = @as(u3, @truncate(y)) ^ if (entry.v_flip.read()) 7 else @as(u3, 0);
|
||||
const col = @as(u3, @truncate(x)) ^ if (entry.h_flip.read()) 7 else @as(u3, 0);
|
||||
const tile_addr = char_base + (tile_id * tile_len) + (row * tile_row_offset) + if (is_8bpp) col else col >> 1;
|
||||
|
||||
const tile = bus.read(u8, 0x0600_0000 + tile_addr);
|
||||
// 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;
|
||||
|
||||
if (pal_id != 0) self.drawBackgroundPixel(layer, i, bus.read(u16, @as(u32, 0x0500_0000) + pal_id * 2));
|
||||
}
|
||||
}
|
||||
|
||||
inline fn get4bppTilePalette(pal_bank: u4, col: u3, tile: u8) u8 {
|
||||
const nybble_tile = tile >> ((col & 1) << 2) & 0xF;
|
||||
if (nybble_tile == 0) return 0;
|
||||
|
||||
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];
|
||||
_ = maybe_btm;
|
||||
|
||||
const bgr555 = switch (maybe_top) {
|
||||
.set => |px| px,
|
||||
else => 0xAAAA,
|
||||
};
|
||||
|
||||
frame_buf[i] = rgba888(bgr555);
|
||||
}
|
||||
|
||||
self.scanline.reset();
|
||||
}
|
||||
|
||||
// TODO: Comment this + get a better understanding
|
||||
fn tilemapOffset(size: u2, x: u32, y: u32) u32 {
|
||||
// Current Row: (y % PIXEL_COUNT) / 8
|
||||
// Current COlumn: (x % PIXEL_COUNT) / 8
|
||||
// Length of 1 row of Screen Entries: 0x40
|
||||
// Length of 1 Screen Entry: 0x2 is the size of a screen entry
|
||||
@setRuntimeSafety(false);
|
||||
|
||||
return switch (size) {
|
||||
0 => (x % 256 / 8) * 2 + (y % 256 / 8) * 0x40, // 256 x 256
|
||||
1 => blk: {
|
||||
// 512 x 256
|
||||
const offset: u32 = if (x & 0x1FF > 0xFF) 0x800 else 0;
|
||||
break :blk offset + (x % 256 / 8) * 2 + (y % 256 / 8) * 0x40;
|
||||
},
|
||||
2 => blk: {
|
||||
// 256 x 512
|
||||
const offset: u32 = if (y & 0x1FF > 0xFF) 0x800 else 0;
|
||||
break :blk offset + (x % 256 / 8) * 2 + (y % 256 / 8) * 0x40;
|
||||
},
|
||||
3 => blk: {
|
||||
// 512 x 512
|
||||
const offset: u32 = if (x & 0x1FF > 0xFF) 0x800 else 0;
|
||||
const offset_2: u32 = if (y & 0x1FF > 0xFF) 0x800 else 0;
|
||||
break :blk offset + offset_2 + (x % 256 / 8) * 2 + (y % 512 / 8) * 0x40;
|
||||
},
|
||||
};
|
||||
}
|
||||
|
||||
fn drawBackgroundPixel(self: *@This(), comptime layer: u2, i: u32, bgr555: u16) void {
|
||||
_ = layer;
|
||||
|
||||
self.scanline.top()[i] = Scanline.Pixel.from(.Background, bgr555);
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
const Scanline = struct {
|
||||
const Pixel = union(enum) {
|
||||
// TODO: Rename
|
||||
const Layer = enum { Background, Sprite };
|
||||
|
||||
set: u16,
|
||||
obj_set: u16,
|
||||
unset: void,
|
||||
hidden: void,
|
||||
|
||||
fn from(comptime layer: Layer, bgr555: u16) Pixel {
|
||||
return switch (layer) {
|
||||
.Background => .{ .set = bgr555 },
|
||||
.Sprite => .{ .obj_set = bgr555 },
|
||||
};
|
||||
}
|
||||
|
||||
pub fn isSet(self: @This()) bool {
|
||||
return switch (self) {
|
||||
.set, .obj_set => true,
|
||||
.unset, .hidden => false,
|
||||
};
|
||||
}
|
||||
};
|
||||
|
||||
layers: [2][]Pixel,
|
||||
buf: []Pixel,
|
||||
|
||||
fn init(allocator: std.mem.Allocator) !@This() {
|
||||
const buf = try allocator.alloc(Pixel, width * 2); // Top & Bottom Scanline
|
||||
@memset(buf, .unset);
|
||||
|
||||
return .{
|
||||
// Top & Bototm Layers
|
||||
.layers = [_][]Pixel{ buf[0..][0..width], buf[width..][0..width] },
|
||||
.buf = buf,
|
||||
};
|
||||
}
|
||||
|
||||
fn reset(self: *@This()) void {
|
||||
@memset(self.buf, .unset);
|
||||
}
|
||||
|
||||
fn deinit(self: @This(), allocator: std.mem.Allocator) void {
|
||||
allocator.free(self.buf);
|
||||
}
|
||||
|
||||
fn top(self: *@This()) []Pixel {
|
||||
return self.layers[0];
|
||||
}
|
||||
|
||||
fn btm(self: *@This()) []Pixel {
|
||||
return self.layers[1];
|
||||
}
|
||||
};
|
||||
|
||||
const bg = struct {
|
||||
const Text = struct {
|
||||
const io = @import("../nds9/io.zig");
|
||||
|
||||
/// Read / Write
|
||||
cnt: io.Bgcnt = .{ .raw = 0x0000 },
|
||||
/// Write Only
|
||||
hofs: io.Hofs = .{ .raw = 0x0000 },
|
||||
/// Write Only
|
||||
vofs: io.Vofs = .{ .raw = 0x0000 },
|
||||
};
|
||||
|
||||
const Screen = struct {
|
||||
const Entry = extern union {
|
||||
const Bitfield = @import("bitfield").Bitfield;
|
||||
const Bit = @import("bitfield").Bit;
|
||||
|
||||
tile_id: Bitfield(u16, 0, 10),
|
||||
h_flip: Bit(u16, 10),
|
||||
v_flip: Bit(u16, 11),
|
||||
pal_bank: Bitfield(u16, 12, 4),
|
||||
raw: u16,
|
||||
};
|
||||
};
|
||||
|
||||
const Affine = @compileError("TODO: Implement Affine Backgrounds");
|
||||
};
|
||||
|
||||
inline fn rgba888(bgr555: u16) u32 {
|
||||
const b: u32 = bgr555 >> 10 & 0x1F;
|
||||
const g: u32 = bgr555 >> 5 & 0x1F;
|
||||
|
|
|
|||
Loading…
Reference in New Issue