我一直在尝试将UIImage裁剪成一个圆形。 我现在使用的是在其他答案中很流行的代码,但是尽管我得到了一个圆形,它的边缘非常锯齿状而不是平滑的。 有人可以帮忙吗?我怎样才能得到一个完美、平滑的圆形?
我用来创建遮罩的代码是:
(UIImage*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage {
CGImageRef imageNoAlpha = image.CGImage;
CGColorSpaceRef cs = CGColorSpaceCreateDeviceRGB();
CGFloat width = CGImageGetWidth(imageNoAlpha);
CGFloat height = CGImageGetWidth(imageNoAlpha);
CGContextRef ctxWithAlpha = CGBitmapContextCreate(nil, width, height, 8, 4*width, cs, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(ctxWithAlpha, CGRectMake(0, 0, width, height), imageNoAlpha);
CGImageRef imageWithAlpha = CGBitmapContextCreateImage(ctxWithAlpha);
CGImageRef maskRef = maskImage.CGImage;
CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
CGImageGetHeight(maskRef),
CGImageGetBitsPerComponent(maskRef),
CGImageGetBitsPerPixel(maskRef),
CGImageGetBytesPerRow(maskRef),
CGImageGetDataProvider(maskRef), NULL, false);
CGImageRef masked = CGImageCreateWithMask(imageWithAlpha, mask);
UIImage* retImage= [UIImage imageWithCGImage:masked];
UIImage* retImageFixed = [retImage transparentBorderImage:1];
CGImageRelease(mask);
CGImageRelease(masked);
CGImageRelease(imageWithAlpha);
CGContextRelease(ctxWithAlpha);
CGColorSpaceRelease(cs);
return retImageFixed;
提前致谢...