thirdparty/scummvm
2
0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

GRAPHICS: Optimise PixelBuffer::getValueAt and PixelBuffer::setPixelAt.

Browse source 
Avoid doing a lot of operations just to move 2 or 4 bytes around.
Inline these methods as they are hot-spots and do very little: call
overhead becomes significant.
This commit is contained in:
Vincent Pelletier 2016-07-19 02:55:33 +02:00
parent d467980499
commit f4554c1541
2 changed files with 36 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

32
graphics/pixelbuffer.cpp
View file

@ -86,20 +86,6 @@ void PixelBuffer::clear(int length) {
memset(_buffer, 0, length);
}
void PixelBuffer::setPixelAt(int pixel, uint32 value) {
#if defined(SCUMM_BIG_ENDIAN)
byte *buffer = _buffer + pixel * _format.bytesPerPixel;
for (int i = 0; i < _format.bytesPerPixel; ++i) {
buffer[i] = value >> ((_format.bytesPerPixel - i - 1) * 8) & 0xFF;
}
#elif defined(SCUMM_LITTLE_ENDIAN)
byte *buffer = _buffer + pixel * _format.bytesPerPixel;
for (int i = 0; i < _format.bytesPerPixel; ++i) {
buffer[i] = value >> (i * 8) & 0xFF;
}
#endif
}
void PixelBuffer::copyBuffer(int thisFrom, int otherFrom, int length, const PixelBuffer &buf) {
if (buf._format == _format) {
memcpy(_buffer + thisFrom * _format.bytesPerPixel, buf._buffer + otherFrom * _format.bytesPerPixel, length * _format.bytesPerPixel);
@ -112,24 +98,6 @@ void PixelBuffer::copyBuffer(int thisFrom, int otherFrom, int length, const Pixe
}
}
uint32 PixelBuffer::getValueAt(int i) const {
#if defined(SCUMM_BIG_ENDIAN)
byte *buffer = _buffer + i * _format.bytesPerPixel;
uint32 p = buffer[0] << ((_format.bytesPerPixel - 1) * 8);
for (int l = 1; l < _format.bytesPerPixel; ++l) {
p = p | (buffer[l] << (8 * (_format.bytesPerPixel - l - 1)));
}
return p;
#elif defined(SCUMM_LITTLE_ENDIAN)
byte *buffer = _buffer + i * _format.bytesPerPixel;
uint32 p = buffer[0];
for (int l = 1; l < _format.bytesPerPixel; ++l) {
p = p | (buffer[l] << (8 * l));
}
return p;
#endif
}
PixelBuffer &PixelBuffer::operator=(const PixelBuffer &buf) {
_buffer = buf._buffer;
_format = buf._format;