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fixed coarse x overflow

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Lauchmelder 2022-03-07 13:03:31 +01:00
parent 2c576740fa
commit a4e4a16eaa
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GPG key ID: C2403C69D78F011D
2 changed files with 53 additions and 29 deletions
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78
src/PPU.cpp
View file

@ -138,6 +138,8 @@ void PPU::Tick()
if (y == 241 && x == 1)
{
// Set flag and send NMI if necessary
// std::fill(OAM.begin(), OAM.end(), 0x00);
ppustatus.Flag.VBlankStarted = 1;
if (ppuctrl.Flag.VBlankNMI)
bus->NMI();
@ -175,6 +177,27 @@ void PPU::Tick()
}
if (x == 256)
{
current.FineY++;
if (current.FineY == 0)
{
if (current.CoarseY == 29)
{
current.CoarseY = 0;
current.NametableSel ^= 0x2;
}
else if (current.CoarseY == 31)
{
current.CoarseY = 0;
}
else
{
current.CoarseY++;
}
}
}
if (x < 256 && y < 240)
{
Pixel bgPixel = GetBackgroundPixel();
@ -434,26 +457,14 @@ void PPU::EvaluateBackgroundTiles()
loAttribute.Lo = ((attributeHalfNybble & 1) ? 0xFF : 0x00);
hiAttribute.Lo = ((attributeHalfNybble & 2) ? 0xFF : 0x00);
current.CoarseX++;
if (x == 256)
if (current.CoarseX == 0x1F)
{
current.FineY++;
if (current.FineY == 0)
{
if (current.CoarseY == 29)
{
current.CoarseY = 0;
current.NametableSel ^= 0x2;
}
else if (current.CoarseY == 31)
{
current.CoarseY = 0;
}
else
{
current.CoarseY++;
}
}
current.NametableSel ^= 0x1;
current.CoarseX = 0x00;
}
else
{
current.CoarseX++;
}
fetchPhase = FetchingPhase::NametableByte;
@ -474,7 +485,7 @@ void PPU::EvaluateSprites()
if (scanlineType != ScanlineType::PreRender)
{
OAMOverrideSignal = (x <= 64);
OAMOverrideSignal = (x <= 64) * 0xFF;
// Secondary OAM clear
if (x < 64)
@ -500,11 +511,14 @@ void PPU::EvaluateSprites()
// Find free slot
secondaryOAM[freeSecondaryOAMSlot] = spriteYCoord;
Word diff = y - spriteYCoord;
if (diff == 0x6)
volatile int dkjhfdjf = 32;
if (y - spriteYCoord < 8 + ppuctrl.Flag.SpriteSize * 8) // Choose between 8x8 and 8x16 mode
{
secondaryOAM[freeSecondaryOAMSlot + 1] = ReadOAM(4 * n + 1);
secondaryOAM[freeSecondaryOAMSlot + 2] = ReadOAM(4 * n + 2);
secondaryOAM[freeSecondaryOAMSlot + 3] = ReadOAM(4 * n + 3);
secondaryOAM[freeSecondaryOAMSlot + 1] = ReadOAM(oamaddr + 4 * n + 1);
secondaryOAM[freeSecondaryOAMSlot + 2] = ReadOAM(oamaddr + 4 * n + 2);
secondaryOAM[freeSecondaryOAMSlot + 3] = ReadOAM(oamaddr + 4 * n + 3);
freeSecondaryOAMSlot += 4;
}
@ -552,21 +566,24 @@ void PPU::EvaluateSprites()
case FetchingPhase::PatternTableLo:
{
Byte spriteFineY = y - secondaryOAM[4 * currentlyEvaluatedSprite];
Byte tileNumber = secondaryOAM[4 * currentlyEvaluatedSprite + 1] + (spriteFineY >> 3);
Word spriteFineY = y - secondaryOAM[4 * currentlyEvaluatedSprite];
Word tileNumber = secondaryOAM[4 * currentlyEvaluatedSprite + 1] + (spriteFineY >> 3);
sprites[currentlyEvaluatedSprite].Lo = Read(((Word)ppuctrl.Flag.SpritePatternTableAddr << 12) | (tileNumber << 4) + spriteFineY);
sprites[currentlyEvaluatedSprite].Lo = Read((((Word)ppuctrl.Flag.SpritePatternTableAddr << 12) | (tileNumber << 4)) + spriteFineY);
fetchPhase = FetchingPhase::PatternTableHi;
} break;
case FetchingPhase::PatternTableHi:
{
Byte spriteFineY = y - secondaryOAM[4 * currentlyEvaluatedSprite];
Word spriteFineY = y - secondaryOAM[4 * currentlyEvaluatedSprite];
Byte tileNumber = secondaryOAM[4 * currentlyEvaluatedSprite + 1] + (spriteFineY >> 3);
sprites[currentlyEvaluatedSprite].Hi = Read(((Word)ppuctrl.Flag.SpritePatternTableAddr << 12) | (tileNumber << 4) + 8 + spriteFineY);
sprites[currentlyEvaluatedSprite].Hi = Read((((Word)ppuctrl.Flag.SpritePatternTableAddr << 12) | (tileNumber << 4)) + 8 + spriteFineY);
if (sprites[currentlyEvaluatedSprite].Hi != 0x00 && sprites[currentlyEvaluatedSprite].Counter == 0x88)
volatile int dkjf = 3;
if (currentlyEvaluatedSprite * 4 >= freeSecondaryOAMSlot)
{
sprites[currentlyEvaluatedSprite].Lo = 0x00;
@ -639,7 +656,7 @@ Pixel PPU::GetSpritePixel()
continue;
// If sprite is active, determine the current pixel
Byte loBit = (sprite.Hi & 0x80) >> 7;
Byte loBit = (sprite.Lo & 0x80) >> 7;
Byte hiBit = (sprite.Hi & 0x80) >> 7;
uint8_t color = (hiBit << 1) | loBit;
@ -653,6 +670,9 @@ Pixel PPU::GetSpritePixel()
if (color == 0x00)
palette = 0x00;
sprite.Lo <<= 1;
sprite.Hi <<= 1;
returnValue.color = color;
returnValue.palette = palette;
returnValue.priority = (sprite.Latch >> 5) & 0x1;

4
src/controllers/Controller.hpp
View file

@ -27,6 +27,10 @@ public:
{
Byte output = outRegister & 1;
outRegister >>= 1;
if (output != 0)
volatile int jdfk = 3;
return (output << outPin);
}