All colors are specified in terms of a 24-bit color value, represented by the class TRgb. This 24 bit value is mapped down to device-level values by the graphics device or printer driver.

Note that:

  • Colors can be specified logically (for example the window background color), as well as physically. The UI Graphics Utilities API contains a list of logical Colors (TLogicalColor) and provides the means to convert them into RGB values.

  • The window server defines display modes that represent color resolutions. In each display mode, as enumerated by TDisplayMode, a unique index can represent each physical color supported. TRgb can map such indices onto a full RGB value.

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