public Gpu(IDisplay display, InterruptManager interruptManager, Dma dma, Ram oamRam, bool gbc)
{
_r = new MemoryRegisters(GpuRegister.Values().ToArray());
_lcdc = new Lcdc();
_interruptManager = interruptManager;
_gbc = gbc;
_videoRam0 = new Ram(0x8000, 0x2000);
_videoRam1 = gbc ? new Ram(0x8000, 0x2000) : null;
_oamRam = oamRam;
_dma = dma;
_bgPalette = new ColorPalette(0xff68);
_oamPalette = new ColorPalette(0xff6a);
_oamPalette.FillWithFf();
_oamSearchPhase = new OamSearch(oamRam, _lcdc, _r);
_pixelTransferPhase = new PixelTransfer(_videoRam0, _videoRam1, oamRam, display, _lcdc, _r, gbc, _bgPalette,
_oamPalette);
_hBlankPhase = new HBlankPhase();
_vBlankPhase = new VBlankPhase();
_mode = Mode.OamSearch;
_phase = _oamSearchPhase.Start();
_display = display;
}
private void DisableLcd()
{
_r.Put(GpuRegister.Ly, 0);
_ticksInLine = 0;
_phase = _hBlankPhase.Start(250);
_mode = Mode.HBlank;
_lcdEnabled = false;
_lcdEnabledDelay = -1;
_display.Enabled = false;
}
public Mode?Tick()
{
if (!_lcdEnabled)
{
if (_lcdEnabledDelay != -1)
{
if (--_lcdEnabledDelay == 0)
{
_display.Enabled = true;
_lcdEnabled = true;
}
}
}
if (!_lcdEnabled)
{
return(null);
}
var oldMode = _mode;
_ticksInLine++;
if (_phase.Tick())
{
// switch line 153 to 0
if (_ticksInLine == 4 && _mode == Mode.VBlank && _r.Get(GpuRegister.Ly) == 153)
{
_r.Put(GpuRegister.Ly, 0);
RequestLycEqualsLyInterrupt();
}
}
else
{
switch (oldMode)
{
case Mode.OamSearch:
_mode = Mode.PixelTransfer;
_phase = _pixelTransferPhase.Start(_oamSearchPhase.GetSprites());
break;
case Mode.PixelTransfer:
_mode = Mode.HBlank;
_phase = _hBlankPhase.Start(_ticksInLine);
RequestLcdcInterrupt(3);
break;
case Mode.HBlank:
_ticksInLine = 0;
if (_r.PreIncrement(GpuRegister.Ly) == 144)
{
_mode = Mode.VBlank;
_phase = _vBlankPhase.Start();
_interruptManager.RequestInterrupt(InterruptManager.InterruptType.VBlank);
RequestLcdcInterrupt(4);
}
else
{
_mode = Mode.OamSearch;
_phase = _oamSearchPhase.Start();
}
RequestLcdcInterrupt(5);
RequestLycEqualsLyInterrupt();
break;
case Mode.VBlank:
_ticksInLine = 0;
if (_r.PreIncrement(GpuRegister.Ly) == 1)
{
_mode = Mode.OamSearch;
_r.Put(GpuRegister.Ly, 0);
_phase = _oamSearchPhase.Start();
RequestLcdcInterrupt(5);
}
else
{
_phase = _vBlankPhase.Start();
}
RequestLycEqualsLyInterrupt();
break;
}
}
if (oldMode == _mode)
{
return(null);
}
return(_mode);
}
