Color Support

Module Description

Color modification APIs.

Functions
COLORREF WINAPI	ScaleColorRef (COLORREF color, BYTE mul, BYTE div)
COLORREF WINAPI	GradientColor (COLORREF c1, COLORREF c2, WORD Ix, WORD Length)
COLORREF WINAPI	GrayScaleColor (COLORREF rgb)
DWORD __cdecl	_swapRGB (DWORD rgba)
DWORD __cdecl	_swapRGB2 (DWORD rgb)

Function Documentation

ScaleColorRef()

COLORREF WINAPI ScaleColorRef	(	COLORREF	color,
		BYTE	mul,
		BYTE	div
	)

ScaleColorRef scales the R/G/B values of color by a ratio.
The resulting R/G/B components are constrained to byte range.

Definition at line 558 of file GdiUtil.cpp.

GradientColor()

COLORREF WINAPI GradientColor	(	COLORREF	c1,
		COLORREF	c2,
		WORD	Ix,
		WORD	Length
	)

GradientColor produces a smooth color crossfade from c1 to c2.

Parameters

c1,c2	Starting and ending color.
Length	The desired run length from c1 to c2, inclusive.
Ix	Zero-based step nr.

Returns the color at step Ix.

GrayScaleColor()

COLORREF WINAPI GrayScaleColor

(

COLORREF

rgb

)

GrayScaleColor converts an RGB value to grayscale.
The luminance of the return value is an sRGB weighted combination of R/G/B.

Definition at line 596 of file GdiUtil.cpp.

_swapRGB()

DWORD __cdecl _swapRGB

(

DWORD

rgba

)

_swapRGB swaps the RGB order of rgba, preserving the alpha/flag value.
Used to convert between e.g COLORREF <-> RGBQUAD.
Example

LITERAL( DWORD, rgbQuad ) = _swapRGB( colorRef );
colorRef = _swapRGB( LITERAL( DWORD, rgbQuad ));

Defined in _bswap.asm

_swapRGB2()

DWORD __cdecl _swapRGB2

(

DWORD

rgb

)

_swapRGB2 swaps the RGB order of rgb, clearing the alpha/flag value.
See also _swapRGB() Defined in _bswap.asm