Loading a CGImage or NSImage from a file using a standard image format (jpeg, gif, png et.) is all very simple.
However, I now need to create a CGImage from an array in bytes in memory generated using libfreetype. Its really easy to create OpenGL textures from an array of formatted bytes, and I can see how to create a CGBitmapContext to write to. But I can't seem to find an easy way to create a CGImage from a raw pixel array.
Using CFData can make the above code simpler. Here is the code.
// raw pixel data memory of 64 * 64 pixel size
UInt8 pixelData[64 * 64 * 3];
// fill the raw pixel buffer with arbitrary gray color for test
for(size_t ui = 0; ui < 64 * 64 * 3; ui++)
pixelData[ui] = 210;
CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB();
CFDataRef rgbData = CFDataCreate(NULL, pixelData, 64 * 64 * 3);
CGDataProviderRef provider = CGDataProviderCreateWithCFData(rgbData);
CGImageRef rgbImageRef = CGImageCreate(64, 64, 8, 24, 64 * 3, colorspace, kCGBitmapByteOrderDefault, provider, NULL, true, kCGRenderingIntentDefault);
CFRelease(rgbData);
CGDataProviderRelease(provider);
CGColorSpaceRelease(colorspace);
// use the created CGImage
CGImageRelease(rgbImageRef);