public VPC(PCEngine pce, VDC vdc1, VDC vdc2, VCE vce, HuC6280 cpu)
{
PCE = pce;
VDC1 = vdc1;
VDC2 = vdc2;
VCE = vce;
CPU = cpu;
// latch initial video buffer
FrameBuffer = vdc1.GetVideoBuffer();
FrameWidth = vdc1.BufferWidth;
FrameHeight = vdc1.BufferHeight;
}
public VPC(PCEngine pce, VDC vdc1, VDC vdc2, VCE vce, HuC6280 cpu)
{
PCE = pce;
VDC1 = vdc1;
VDC2 = vdc2;
VCE = vce;
CPU = cpu;
// latch initial video buffer
FrameBuffer = vdc1.GetVideoBuffer();
FrameWidth = vdc1.BufferWidth;
FrameHeight = vdc1.BufferHeight;
}
public void ExecFrame(bool render)
{
// Determine the effective priority mode.
if (Window1Width < 0x40 && Window2Width < 0x40)
{
EffectivePriorityMode = PriorityModeSlot3 >> 2;
}
else if (Window2Width > 512)
{
EffectivePriorityMode = PriorityModeSlot1 >> 2;
}
else
{
Console.WriteLine("Unsupported VPC window settings");
EffectivePriorityMode = 0;
}
// Latch frame dimensions and framebuffer, for purely dumb reasons
FrameWidth = VDC1.BufferWidth;
FrameHeight = VDC1.BufferHeight;
FrameBuffer = VDC1.GetVideoBuffer();
int ScanLine = 0;
int ActiveDisplayStartLine = VDC1.DisplayStartLine;
while (true)
{
VDC1.ScanLine = ScanLine;
VDC2.ScanLine = ScanLine;
int VBlankLine = ActiveDisplayStartLine + VDC1.Registers[VDW] + 1;
if (VBlankLine > 261)
{
VBlankLine = 261;
}
VDC1.ActiveLine = ScanLine - ActiveDisplayStartLine;
VDC2.ActiveLine = VDC1.ActiveLine;
bool InActiveDisplay = (ScanLine >= ActiveDisplayStartLine) && (ScanLine < VBlankLine);
if (ScanLine == ActiveDisplayStartLine)
{
VDC1.RCRCounter = 0x40;
VDC2.RCRCounter = 0x40;
}
if (ScanLine == VBlankLine)
{
VDC1.UpdateSpriteAttributeTable();
VDC2.UpdateSpriteAttributeTable();
}
if (VDC1.RCRCounter == (VDC1.Registers[RCR] & 0x3FF))
{
if (VDC1.RasterCompareInterruptEnabled)
{
VDC1.StatusByte |= VDC.StatusRasterCompare;
CPU.IRQ1Assert = true;
}
}
if (VDC2.RCRCounter == (VDC2.Registers[RCR] & 0x3FF))
{
if (VDC2.RasterCompareInterruptEnabled)
{
VDC2.StatusByte |= VDC.StatusRasterCompare;
CPU.IRQ1Assert = true;
}
}
CPU.Execute(24);
if (InActiveDisplay)
{
if (ScanLine == ActiveDisplayStartLine)
{
VDC1.BackgroundY = VDC1.Registers[BYR];
VDC2.BackgroundY = VDC2.Registers[BYR];
}
else
{
VDC1.BackgroundY++;
VDC1.BackgroundY &= 0x01FF;
VDC2.BackgroundY++;
VDC2.BackgroundY &= 0x01FF;
}
}
CPU.Execute(VDC1.HBlankCycles - 24);
if (InActiveDisplay)
{
if (render)
{
RenderScanLine();
}
}
if (ScanLine == VBlankLine && VDC1.VBlankInterruptEnabled)
{
VDC1.StatusByte |= VDC.StatusVerticalBlanking;
}
if (ScanLine == VBlankLine && VDC2.VBlankInterruptEnabled)
{
VDC2.StatusByte |= VDC.StatusVerticalBlanking;
}
if (ScanLine == VBlankLine + 4 && VDC1.SatDmaPerformed)
{
VDC1.SatDmaPerformed = false;
if ((VDC1.Registers[DCR] & 1) > 0)
{
VDC1.StatusByte |= VDC.StatusVramSatDmaComplete;
}
}
if (ScanLine == VBlankLine + 4 && VDC2.SatDmaPerformed)
{
VDC2.SatDmaPerformed = false;
if ((VDC2.Registers[DCR] & 1) > 0)
{
VDC2.StatusByte |= VDC.StatusVramSatDmaComplete;
}
}
CPU.Execute(2);
if ((VDC1.StatusByte & (VDC.StatusVerticalBlanking | VDC.StatusVramSatDmaComplete)) != 0)
{
CPU.IRQ1Assert = true;
}
if ((VDC2.StatusByte & (VDC.StatusVerticalBlanking | VDC.StatusVramSatDmaComplete)) != 0)
{
CPU.IRQ1Assert = true;
}
CPU.Execute(455 - VDC1.HBlankCycles - 2);
if (InActiveDisplay == false && VDC1.DmaRequested)
{
VDC1.RunDmaForScanline();
}
if (InActiveDisplay == false && VDC2.DmaRequested)
{
VDC2.RunDmaForScanline();
}
VDC1.RCRCounter++;
VDC2.RCRCounter++;
ScanLine++;
if (ScanLine == VCE.NumberOfScanlines)
{
break;
}
}
}
