CGBlendMode.destinationAtop R = S*(1 - Da) + D*Sa Declarationcase destinationAtop See AlsoConstantsCGBlendMode.normalCGBlendMode.multiplyCGBlendMode.screenCGBlendMode.overlayCGBlendMode.darkenCGBlendMode.lightenCGBlendMode.colorDodgeCGBlendMode.colorBurnCGBlendMode.softLightCGBlendMode.hardLightCGBlendMode.differenceCGBlendMode.exclusionCGBlendMode.hueCGBlendMode.saturationCGBlendMode.color