<mini> PorterDuff についてのまとめ

　どこまで使えるか否か。

　Android との互換性を考えると，基本的な PorterDuffMode しか使えないなーという感じですね。

　WinObjC という Windows Runtime 上で動く iOS 互換環境の CoreGraphics でもおなじみのように，ほぼ全てのモードが Windows 上で使えます。唯一，「kCGBlendModePlusDarker」のみシミュレーションできませんね。

※ 表は横スクロールできます

Mode Expression	Android PorterDuff.Mode	Apple CGBlendMode	Direct2D D2D1_COMPOSITE_MODE	Direct2D D2D1_BLEND_MODE
Clear O = 0	△ (Software only: CLEAR)	kCGBlendModeClear	×	×
SourceCopy O = S	SRC	kCGBlendModeCopy	D2D1_COMPOSITE_MODE_SOURCE_COPY	×
DestinationCopy O = D	DST	×	×	×
SourceOver O = S + (1 - Sa) * D	SRC_OVER	kCGBlendModeNormal	D2D1_COMPOSITE_MODE_SOURCE_OVER	×
DestinationOver O = (1 - Da) * S + D	DST_OVER	kCGBlendModeDestinationOver	D2D1_COMPOSITE_MODE_DESTINATION_OVER	×
SourceIn O = Da * S	SRC_IN	kCGBlendModeSourceIn	D2D1_COMPOSITE_MODE_SOURCE_IN	×
DestinationIn O = Sa * D	DST_IN	kCGBlendModeDestinationIn	D2D1_COMPOSITE_MODE_DESTINATION_IN	×
SourceOut O = (1 - Da) * S	SRC_OUT	kCGBlendModeSourceOut	D2D1_COMPOSITE_MODE_SOURCE_OUT	×
DestinationOut O = (1 - Sa) * D	DST_OUT	kCGBlendModeDestinationOut	D2D1_COMPOSITE_MODE_DESTINATION_OUT	×
SourceAtop O = Da * S + (1 - Sa) * D	SRC_ATOP	kCGBlendModeSourceAtop	D2D1_COMPOSITE_MODE_SOURCE_ATOP	×
DestinationAtop O = (1 - Da) * S + Sa * D	DST_ATOP	kCGBlendModeDestinationAtop	D2D1_COMPOSITE_MODE_DESTINATION_ATOP	×
Xor O = (1 - Da) * S + (1 - Sa) * D	XOR	△ (kCGBlendModeXOR)	D2D1_COMPOSITE_MODE_XOR	×
Add O = min(1, S + D)	ADD	kCGBlendModePlusLighter	D2D1_COMPOSITE_MODE_PLUS	×
PlusDarker O = max(0, 1 - (1 - S) - (1 - D))	×	kCGBlendModePlusDarker	×	×
BoundedSourceCopy O = S (範囲内のみ)	×	×	D2D1_COMPOSITE_MODE_BOUNDED_SOURCE_COPY	×
MaskInvert O = (1 - D) * S + (1 - Sa) * D	×	×	D2D1_COMPOSITE_MODE_MASK_INVERT	×
?	×	×	D2D1_COMPOSITE_MODE_FORCE_DWORD	D2D1_BLEND_MODE_FORCE_DWORD
Darken O = (1 - Da) * S + (1 - Sa) * D + min(S, D)	△ (Software only: DARKEN)	kCGBlendModeDarken	×	D2D1_BLEND_MODE_DARKEN
Lighten O = (1 - Da) * S + (1 - Sa) * D + max(S, D)	△ (Software only: LIGHTEN)	kCGBlendModeLighten	×	D2D1_BLEND_MODE_LIGHTEN
Multiply O = S * D	MULTIPLY	kCGBlendModeMultiply	×	D2D1_BLEND_MODE_MULTIPLY
Screen O = S + D - (S * D)	SCREEN	kCGBlendModeScreen	×	D2D1_BLEND_MODE_SCREEN
Overlay O = 2 * Sa * Da * S * D - 2 * (Da - S) * (Sa - D)	△ (Software only: OVERLAY)	kCGBlendModeOverlay	×	D2D1_BLEND_MODE_OVERLAY
ColorDodge	×	kCGBlendModeColorDodge	×	D2D1_BLEND_MODE_COLOR_DODGE
LinearDodge	×	×	×	D2D1_BLEND_MODE_LINEAR_DODGE
ColorBurn	×	kCGBlendModeColorBurn	×	D2D1_BLEND_MODE_COLOR_BURN
LinearBurn	×	×	×	D2D1_BLEND_MODE_LINEAR_BURN
DarkerColor	×	×	×	D2D1_BLEND_MODE_DARKER_COLOR
LighterColor	×	×	×	D2D1_BLEND_MODE_LIGHTER_COLOR
SoftLight	×	kCGBlendModeSoftLight	×	D2D1_BLEND_MODE_SOFT_LIGHT
HardLight	×	kCGBlendModeHardLight	×	D2D1_BLEND_MODE_HARD_LIGHT
Vivid	×	×	×	D2D1_BLEND_MODE_VIVID_LIGHT
LinearLight	×	×	×	D2D1_BLEND_MODE_LINEAR_LIGHT
PinLight	×	×	×	D2D1_BLEND_MODE_PIN_LIGHT
HardMix	×	×	×	D2D1_BLEND_MODE_HARD_MIX
Difference	×	kCGBlendModeDifference	×	D2D1_BLEND_MODE_DIFFERENCE
Exculusion	×	kCGBlendModeExclusion	×	D2D1_BLEND_MODE_EXCLUSION
Hue	×	kCGBlendModeHue	×	D2D1_BLEND_MODE_HUE
Saturation	×	kCGBlendModeSaturation	×	D2D1_BLEND_MODE_SATURATION
Color	×	kCGBlendModeColor	×	D2D1_BLEND_MODE_COLOR
Luminosity	×	kCGBlendModeLuminosity	×	D2D1_BLEND_MODE_LUMINOSITY
Subtract	×	kCGBlendModeLuminosity	×	D2D1_BLEND_MODE_SUBTRACT
Dissolve	×	×	×	D2D1_BLEND_MODE_DISSOLVE

参考用

SetROP2 関数

docs.microsoft.com

docs.microsoft.com

PorterDuff.Mode  |  Android Developers

tech.recruit-mp.co.jp

CGBlendMode - Core Graphics | Apple Developer Documentation

https://skia.org/user/api/skpaint_overview

CoreGraphics の Windows 実装向けの CGContext.h

WinObjC/CGContext.h at master · Microsoft/WinObjC · GitHub