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Difference between revisions of "API-Truecolor"
→Engine initialization protocol
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#*If the setup was not successful, and your engine cannot run in 256 colors, display an error and return. | #*If the setup was not successful, and your engine cannot run in 256 colors, display an error and return. | ||
#*Otherwise, initialize your engine to use the pixel format that getScreenFormat returned, and run normally. | #*Otherwise, initialize your engine to use the pixel format that getScreenFormat returned, and run normally. | ||
==== Example ==== | |||
Here is an example of a simple engine that uses the best color depth available to display an RGB color-cycling gradient. | |||
<syntax type="C++"> | |||
Common::Error QuuxEngine::run() { | |||
Graphics::PixelFormat format = _system->getSupportedFormats().front(); | |||
initGraphics(640, 480, true, &format); | |||
format = _system->getScreenFormat(); | |||
byte *offscreenBuffer = (byte *)malloc(640 * 480 * format.bytesPerPixel); | |||
if (format.bytesPerPixel == 1) { | |||
// Initialize palette to simulate RGB332 | |||
byte palette[1024]; | |||
memset(&palette,0,1024); | |||
byte *dst = palette; | |||
for (byte r = 0; r < 8; r++) { | |||
for (byte g = 0; g < 8; g++) { | |||
for (byte b = 0; b < 4; b++) { | |||
dst[0] = r << 5; | |||
dst[1] = g << 5; | |||
dst[2] = b << 6; | |||
dst[3] = 0; | |||
dst += 4; | |||
} | |||
} | |||
} | |||
_system->setPalette(palette,0,256); | |||
} | |||
uint32 t = 0; | |||
uint32 mask = (1 << (format.bytesPerPixel << 3)) - 1; | |||
while (!shouldQuit()) { | |||
for (int16 y = 0; y < 480; y++) { | |||
uint8 *dst = offscreenBuffer + (y * 640 * format.bytesPerPixel); | |||
for (int16 x = 0; x < 640; x++) { | |||
uint32 color = (x * y) & mask; | |||
t &= (format.bytesPerPixel << 3) - 1; | |||
color = (color << t) | (color >> ((format.bytesPerPixel << 3) - t)); | |||
#ifdef SCUMM_BIG_ENDIAN | |||
for (int i = 0; i < format.bytesPerPixel; i++) | |||
{ | |||
dst[format.bytesPerPixel - i] = color & 0xFF; | |||
color >>= 8; | |||
} | |||
dst += format.bytesPerPixel; | |||
#else | |||
for (int i = format.bytesPerPixel; i > 0; i--) { | |||
*dst++ = color & 0xFF; | |||
color >>= 8; | |||
} | |||
#endif | |||
} | |||
} | |||
Common::Rect r; | |||
r.top = 0; | |||
r.left = 0; | |||
r.bottom = 479; | |||
r.right = 639; | |||
_system->copyRectToScreen(offscreenBuffer, 640 * format.bytesPerPixel, 0, 0, 640, 480); | |||
_system->updateScreen(); | |||
parseEvents(); | |||
_system->delayMillis(66); | |||
t++; | |||
} | |||
return Common::kNoError; | |||
} | |||
</syntax> | |||
=== Backend initialization protocol === | === Backend initialization protocol === | ||