public void RunPPU(int runto)
{
// Idle Scanline - 1 Scanline (AKA Scanline 240)
while (cntScanline == -2 && !tn.bolReset)
{
while (cntScanlineCycle < 341)
{
tsPpu += 5;
cntScanlineCycle++;
if (tsPpu >= runto)
{
return;
}
}
cntScanline = -1;
scanlineChanged = true;
}
// VBLANK Time - 20 Scanlines
if (tsPpu < tn.VBlankTime)
{
if (!tn.bolReset)
{
memory.setVblank(true);
}
// Make sure the system has not just been reset and check to see if Interrupt is enabled on VBLANK
if ((memory.memCPU[0x2000] & 0x80) == 0x80 && !tn.bolReset)
{
tn.NMIHandler();
}
tn.bolReset = false;
tsPpu = tn.VBlankTime; // Do nothing during VBlank until the next 'if' statement is false
//tsPpu += tn.VBlankTime; // (FIX ME!!!!!!) THIS SHOULD BE +=, but it slows down a lot for some reason!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
cntScanline = -1;
cntScanlineCycle = 0;
}
// Check for VBlank over
if (tsPpu >= runto)
{
return;
}
else
{
// Clear Sprite Hit, Sprite Overflow and VBLANK at the end of VBlank
// For reason, clearing Sprite Hit causes the scroll offset to change seemingly randomly
// So I have disabled the reset of that below
if (!tn.bolReset)
{
memory.memCPU[0x2002] &= 0x40; // (FIX) Should also clear Sprite Hit 0
}
// Clear VBlank
memory.setVblank(false);
}
// PreRender Scanline - 1 Scanline
while (cntScanline == -1)
{
while (cntScanlineCycle < 340)
{
tsPpu += 5;
cntScanlineCycle++;
if (tsPpu >= runto)
{
return;
}
}
pixelM = 0;
cntScanlineCycle = 0;
cntScanline++;
scanlineChanged = true;
}
// Render Scanlines - 240 Scanlines
while (cntScanline < 240)
{
// Set Rendering TRUE
tn.rendering = true;
while (cntScanlineCycle < 256)
{
if ((memory.memCPU[0x2001] & 0x08) == 0x08 || (memory.memCPU[0x2001] & 0x10) == 0x10)
{
renderPixel();
}
pixelM++;
tsPpu += 5;
cntScanlineCycle++;
if (tsPpu >= runto)
{
return;
}
}
while (cntScanlineCycle < 341)
{
tsPpu += 5;
cntScanlineCycle++;
if (tsPpu >= runto)
{
return;
}
}
cntScanlineCycle = 0;
cntScanline++;
scanlineChanged = true;
}
if (cntScanline >= 240)
{
// Set Rendering to FALSE
tn.rendering = false;
tsPpu = 0;
bolReadyToRender = true;
cntScanline = -2;
}
}
private void btnVBlankToggle_Click(object sender, EventArgs e)
{
//bolSetVBlank = true;
memory.setVblank(!memory.bolVBlank);
btnVBlankToggle.Text = "VBlank:" + Convert.ToString(memory.bolVBlank);
}
