No that's not what it means, and yes, you can specify RGB values; probably just not in the way you might be thinking. Quartz uses something known as CGColorSpaceRef
, which you can think of as multidimensional — and each dimension represents a specific color component. An example would be the colors in the RGB color space, as three dimensions (red, green, and blue). The intensity of each component is represented by floating point values, and their range and meaning depends on the color space in question.
This should give you more concise information that you're looking for:
Specifically take a look at:
CGColorCreateGenericRGB
Creates a color in the Generic RGB color space.
CGColorRef CGColorCreateGenericRGB(
CGFloat red,
CGFloat green,
CGFloat blue,
CGFloat alpha
);
and also the section on Constant Colors