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Skia
2D Graphics Library
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#include "include/core/SkTypes.h"
Go to the source code of this file.
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SK_API bool | SkBlendMode_AsCoeff (SkBlendMode mode, SkBlendModeCoeff *src, SkBlendModeCoeff *dst) |
Returns true if 'mode' is a coefficient-based blend mode (<= kLastCoeffMode). More... | |
SK_API const char * | SkBlendMode_Name (SkBlendMode blendMode) |
Returns name of blendMode as null-terminated C string. More... | |
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Blends are operators that take in two colors (source, destination) and return a new color.
Many of these operate the same on all 4 components: red, green, blue, alpha. For these, we just document what happens to one component, rather than naming each one separately.
Different SkColorTypes have different representations for color components: 8-bit: 0..255 6-bit: 0..63 5-bit: 0..31 4-bit: 0..15 floats: 0...1
The documentation is expressed as if the component values are always 0..1 (floats).
For brevity, the documentation uses the following abbreviations s : source d : destination sa : source alpha da : destination alpha
Results are appreviated r : if all 4 components are computed in the same manner ra : result alpha component rc : result "color": red, green, blue components
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For Porter-Duff SkBlendModes (those <= kLastCoeffMode), these coefficients describe the blend equation used.
Coefficient-based blend modes specify an equation: ('dstCoeff' * dst + 'srcCoeff' * src), where the coefficient values are constants, functions of the src or dst alpha, or functions of the src or dst color.
SK_API bool SkBlendMode_AsCoeff | ( | SkBlendMode | mode, |
SkBlendModeCoeff * | src, | ||
SkBlendModeCoeff * | dst | ||
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Returns true if 'mode' is a coefficient-based blend mode (<= kLastCoeffMode).
If true is returned, the mode's src and dst coefficient functions are set in 'src' and 'dst'.
SK_API const char* SkBlendMode_Name | ( | SkBlendMode | blendMode | ) |
Returns name of blendMode as null-terminated C string.