iOS图片混合模式

有需求是保留image1上的褶皱（视觉上），而替换不同的花色
    UIGraphicsBeginImageContextWithOptions(newSize, NO, 1.f);
    [image1 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeOverlay alpha:1.f];
    [image2 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeSoftLight alpha:0.7f];
    UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

这里列一下图片的混合模式

typedef CF_ENUM (int32_t, CGBlendMode) {
    kCGBlendModeNormal,
    kCGBlendModeMultiply,
    kCGBlendModeScreen,
    kCGBlendModeOverlay,
    kCGBlendModeDarken,
    kCGBlendModeLighten,
    kCGBlendModeColorDodge,
    kCGBlendModeColorBurn,
    kCGBlendModeSoftLight,
    kCGBlendModeHardLight,
    kCGBlendModeDifference,
    kCGBlendModeExclusion,
    kCGBlendModeHue,
    kCGBlendModeSaturation,
    kCGBlendModeColor,
    kCGBlendModeLuminosity,
    kCGBlendModeClear,                  /* R = 0 */
    kCGBlendModeCopy,                   /* R = S */
    kCGBlendModeSourceIn,               /* R = S*Da */
    kCGBlendModeSourceOut,              /* R = S*(1 - Da) */
    kCGBlendModeSourceAtop,             /* R = S*Da + D*(1 - Sa) */
    kCGBlendModeDestinationOver,        /* R = S*(1 - Da) + D */
    kCGBlendModeDestinationIn,          /* R = D*Sa */
    kCGBlendModeDestinationOut,         /* R = D*(1 - Sa) */
    kCGBlendModeDestinationAtop,        /* R = S*(1 - Da) + D*Sa */
    kCGBlendModeXOR,                    /* R = S*(1 - Da) + D*(1 - Sa) */
    kCGBlendModePlusDarker,             /* R = MAX(0, (1 - D) + (1 - S)) */
    kCGBlendModePlusLighter             /* R = MIN(1, S + D) */
};

具体什么样的效果需要动手试试了。