6.11 Gamut Querying Functions

This section describes the gamut querying functions that Xlib provides. These functions allow the client to query the boundary of the screen's color gamut in terms of the CIE L*a*b*, CIE L*u*v*, and TekHVC color spaces. Functions are also provided that allow you to query the color specification of:

• White (full intensity red, green, and blue)

• Red (full intensity red while green and blue are zero)

• Green (full intensity green while red and blue are zero)

• Blue (full intensity blue while red and green are zero)

• Black (zero intensity red, green, and blue)

The white point associated with color specifications passed to and returned from these gamut querying functions is assumed to be the Screen White Point. This is a reasonable assumption, because the client is trying to query the screen's color gamut.

The following naming convention is used for the Max and Min functions:

Xcms<color_space>QueryMax<dimensions>
Xcms<color_space>QueryMin<dimensions>

The <dimensions> consists of a letter or letters that identify the dimensions of the color space that are not fixed. For example, XcmsTekHVCQueryMaxC() is given a fixed Hue and Value for which maximum Chroma is found.

Next: Red, Green, and Blue Queries

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Christophe Tronche, [email protected]