diff options
Diffstat (limited to 'engines/cine/pal.cpp')
| -rw-r--r-- | engines/cine/pal.cpp | 69 |
1 files changed, 57 insertions, 12 deletions
diff --git a/engines/cine/pal.cpp b/engines/cine/pal.cpp index 9fbb51b915..7f421e6722 100644 --- a/engines/cine/pal.cpp +++ b/engines/cine/pal.cpp @@ -161,6 +161,7 @@ void transformPaletteRange(byte *dstPal, byte *srcPal, int startColor, int stopC } } +/*! \brief Shift byte to the left by given amount (Handles negative shifting amounts too, otherwise this would be trivial). */ byte shiftByteLeft(const byte value, const signed shiftLeft) { if (shiftLeft >= 0) return value << shiftLeft; @@ -168,6 +169,33 @@ byte shiftByteLeft(const byte value, const signed shiftLeft) { return value >> abs(shiftLeft); } +/*! \brief Is given endian type big endian? (Handles native endian type too, otherwise this would be trivial). */ +bool isBigEndian(const EndianType endianType) { + assert(endianType == NATIVE_ENDIAN || endianType == LITTLE_ENDIAN || endianType == BIG_ENDIAN); + + // Handle explicit little and big endian types here + if (endianType != NATIVE_ENDIAN) { + return (endianType == BIG_ENDIAN); + } + + // Handle native endian type here +#if defined(SCUMM_BIG_ENDIAN) + return true; +#elif defined(SCUMM_LITTLE_ENDIAN) + return false; +#else + #error No endianness defined +#endif +} + +/*! \brief Calculate byte position of given bit position in a multibyte variable using defined endianness. */ +int bytePos(const int bitPos, const int numBytes, const bool bigEndian) { + if (bigEndian) + return (numBytes - 1) - (bitPos / 8); + else // little endian + return bitPos / 8; +} + // a.k.a. palRotate Palette &Palette::rotateRight(byte firstIndex, byte lastIndex) { const Color lastColor = _colors[lastIndex]; @@ -183,6 +211,10 @@ uint Palette::colorCount() const { return _colors.size(); } +const EndianType Palette::endianType() const { + return (_bigEndian ? BIG_ENDIAN : LITTLE_ENDIAN); +} + Graphics::PixelFormat Palette::colorFormat() const { return _format; } @@ -199,6 +231,10 @@ void Palette::setColorFormat(const Graphics::PixelFormat format) { _bMax = (1 << _bBits) - 1; } +void Palette::setEndianType(const EndianType endianType) { + _bigEndian = isBigEndian(endianType); +} + // a.k.a. transformPaletteRange Palette &Palette::saturatedAddColor(byte firstIndex, byte lastIndex, signed r, signed g, signed b) { assert(firstIndex < colorCount() && lastIndex < colorCount()); @@ -219,37 +255,42 @@ void Palette::saturatedAddColor(byte index, signed r, signed g, signed b) { _colors[index].b = CLIP<int>(_colors[index].b + b, 0, _bMax); } -Palette &Palette::load(const byte *buf, const uint size, const Graphics::PixelFormat format, const uint numColors) { +Palette &Palette::load(const byte *buf, const uint size, const Graphics::PixelFormat format, const uint numColors, const EndianType endianType) { assert(format.bytesPerPixel * numColors <= size); // Make sure there's enough input space assert(format.aLoss == 8); // No alpha assert(format.rShift / 8 == (format.rShift + MAX<int>(0, 8 - format.rLoss - 1)) / 8); // R must be inside one byte assert(format.gShift / 8 == (format.gShift + MAX<int>(0, 8 - format.gLoss - 1)) / 8); // G must be inside one byte assert(format.bShift / 8 == (format.bShift + MAX<int>(0, 8 - format.bLoss - 1)) / 8); // B must be inside one byte + setEndianType(endianType); setColorFormat(format); _colors.clear(); _colors.resize(numColors); + + const int rBytePos = bytePos(format.rShift, format.bytesPerPixel, isBigEndian(endianType)); + const int gBytePos = bytePos(format.gShift, format.bytesPerPixel, isBigEndian(endianType)); + const int bBytePos = bytePos(format.bShift, format.bytesPerPixel, isBigEndian(endianType)); for (uint i = 0; i < numColors; i++) { // _rMax, _gMax, _bMax are also used as masks here - _colors[i].r = (buf[i * format.bytesPerPixel + (format.rShift / 8)] >> (format.rShift % 8)) & _rMax; - _colors[i].g = (buf[i * format.bytesPerPixel + (format.gShift / 8)] >> (format.gShift % 8)) & _gMax; - _colors[i].b = (buf[i * format.bytesPerPixel + (format.bShift / 8)] >> (format.bShift % 8)) & _bMax; + _colors[i].r = (buf[i * format.bytesPerPixel + rBytePos] >> (format.rShift % 8)) & _rMax; + _colors[i].g = (buf[i * format.bytesPerPixel + gBytePos] >> (format.gShift % 8)) & _gMax; + _colors[i].b = (buf[i * format.bytesPerPixel + bBytePos] >> (format.bShift % 8)) & _bMax; } return *this; } -byte *Palette::save(byte *buf, const uint size) const { - return save(buf, size, colorFormat(), colorCount()); +byte *Palette::save(byte *buf, const uint size, const EndianType endianType) const { + return save(buf, size, colorFormat(), colorCount(), endianType); } -byte *Palette::save(byte *buf, const uint size, const Graphics::PixelFormat format) const { - return save(buf, size, format, colorCount()); +byte *Palette::save(byte *buf, const uint size, const Graphics::PixelFormat format, const EndianType endianType) const { + return save(buf, size, format, colorCount(), endianType); } -byte *Palette::save(byte *buf, const uint size, const Graphics::PixelFormat format, const uint numColors, const byte firstIndex) const { +byte *Palette::save(byte *buf, const uint size, const Graphics::PixelFormat format, const uint numColors, const EndianType endianType, const byte firstIndex) const { assert(format.bytesPerPixel * numColors <= size); // Make sure there's enough output space assert(format.aLoss == 8); // No alpha assert(format.rShift / 8 == (format.rShift + MAX<int>(0, 8 - format.rLoss - 1)) / 8); // R must be inside one byte @@ -269,12 +310,16 @@ byte *Palette::save(byte *buf, const uint size, const Graphics::PixelFormat form const byte gMask = ((1 << (8 - format.gLoss)) - 1) << (format.gShift % 8); const byte bMask = ((1 << (8 - format.bLoss)) - 1) << (format.bShift % 8); + const int rBytePos = bytePos(format.rShift, format.bytesPerPixel, isBigEndian(endianType)); + const int gBytePos = bytePos(format.gShift, format.bytesPerPixel, isBigEndian(endianType)); + const int bBytePos = bytePos(format.bShift, format.bytesPerPixel, isBigEndian(endianType)); + // Save the palette to the output in the specified format for (uint i = firstIndex; i < firstIndex + numColors; i++) { // _rMax, _gMax, _bMax are also used as masks here - buf[i * format.bytesPerPixel + (format.rShift / 8)] |= (shiftByteLeft(_colors[i].r, rShiftLeft) & rMask); - buf[i * format.bytesPerPixel + (format.gShift / 8)] |= (shiftByteLeft(_colors[i].g, gShiftLeft) & gMask); - buf[i * format.bytesPerPixel + (format.bShift / 8)] |= (shiftByteLeft(_colors[i].b, bShiftLeft) & bMask); + buf[i * format.bytesPerPixel + rBytePos] |= (shiftByteLeft(_colors[i].r, rShiftLeft) & rMask); + buf[i * format.bytesPerPixel + gBytePos] |= (shiftByteLeft(_colors[i].g, gShiftLeft) & gMask); + buf[i * format.bytesPerPixel + bBytePos] |= (shiftByteLeft(_colors[i].b, bShiftLeft) & bMask); } // Return the pointer to the output palette |