iOS image处理BlendModes

strMsg = @“kCGBlendModeLighten: 变亮”;

break;

}

case kCGBlendModeColorDodge: {

strMsg = @“kCGBlendModeColorDodge: 颜色变淡”;

break;

}

case kCGBlendModeColorBurn: {

strMsg = @“kCGBlendModeColorBurn: 颜色加深”; //线条颜色（原本）加深，背景色设置为目的色

break;

}

case kCGBlendModeSoftLight: {

strMsg = @“kCGBlendModeSoftLight: 柔光”;

break;

}

case kCGBlendModeHardLight: {

strMsg = @“kCGBlendModeHardLight: 强光”; //全为目的色

break;

}

case kCGBlendModeDifference: {

strMsg = @“kCGBlendModeDifference: 插值”;

break;

}

case kCGBlendModeExclusion: {

strMsg = @“kCGBlendModeExclusion: 排除”;

break;

}

case kCGBlendModeHue: {

strMsg = @“kCGBlendModeHue: 色调”;

break;

}

case kCGBlendModeSaturation: {

strMsg = @“kCGBlendModeSaturation: 饱和度”;

break;

}

case kCGBlendModeColor: {

strMsg = @“kCGBlendModeColor: 颜色”; //感觉将图片线条色设置为白色，背景色设置为目的色，之后再再图片上加一个有透明度的目的色

break;

}

case kCGBlendModeLuminosity: {

strMsg = @“kCGBlendModeLuminosity: 亮度”;

break;

}

//Apple额外定义的枚举

//R: premultiplied result, 表示混合结果

//S: Source, 表示源颜色(Sa对应透明度值: 0.0-1.0)

//D: destination colors with alpha, 表示带透明度的目标颜色(Da对应透明度值: 0.0-1.0)

case kCGBlendModeClear: {

strMsg = @“kCGBlendModeClear: R = 0”; //1.清空（如果图标背景色为白色则为全白）

break;

}

case kCGBlendModeCopy: {

strMsg = @“kCGBlendModeCopy: R = S”; //2全色覆盖整个图片

break;

}

case kCGBlendModeSourceIn: {

strMsg = @“kCGBlendModeSourceIn: R = S*Da”; //3.线条变色

break;

}

case kCGBlendModeSourceOut: {

strMsg = @“kCGBlendModeSourceOut: R = S*(1 - Da)”; //4.背景变为目的色,线条自动变为白色（比如图标线条原为蓝色，会自动变为白色）

break;

}

case kCGBlendModeSourceAtop: {

strMsg = @“kCGBlendModeSourceAtop: R = SDa + D(1 - Sa)”; //5.线条变色，目前感觉和SourceIn效果一致

break;

}

case kCGBlendModeDestinationOver: {

strMsg = @“kCGBlendModeDestinationOver: R = S*( 《大厂前端面试题解析+Web核心总结学习笔记+企业项目实战源码+最新高清讲解视频》无偿开源 徽信搜索公众号【编程进阶路】 1 - Da) + D”; //6.背景色变为目的色，线条色不变

break;

}

case kCGBlendModeDestinationIn: {