标签: cgimagemaskcreate

我实际上要做的是在视图中有一个文本标签"切割"一个文本形状的孔.我试过使用self.mask = uiLabel但是那些拒绝正确定位文本所以我通过Core Graphics接近这个.

这是不起作用的代码(在draw(_ rect: CGRect))中:

    let context = (UIGraphicsGetCurrentContext())!

    // Set mask background color
    context.setFillColor(UIColor.black.cgColor)
    context.fill(rect)

    context.saveGState()


    let paragraphStyle = NSMutableParagraphStyle()
    paragraphStyle.alignment = .center

    let attributes = [
        NSParagraphStyleAttributeName: paragraphStyle,
        NSFontAttributeName: UIFont.systemFont(ofSize: 16, weight: UIFontWeightMedium),
        NSForegroundColorAttributeName: UIColor.white
    ]

    let string = NSString(string: "LOGIN")

    // This wouldn't vertically align so we calculate the string size and create a new rect in which it is vertically aligned
    let size = string.size(attributes: attributes)
    let position = CGRect( …

在我的一个iOS应用程序中,我正在尝试使用切割图像的一部分CGImageMask.我已成功使用以下代码屏蔽图像:

- (UIImage *)maskImage:(UIImage *)referenceImage withMask:(UIImage *)maskImage {

    CGImageRef maskRef = maskImage.CGImage;

    CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                        CGImageGetHeight(maskRef),
                                        CGImageGetBitsPerComponent(maskRef),
                                        CGImageGetBitsPerPixel(maskRef),
                                        CGImageGetBytesPerRow(maskRef),
                                        CGImageGetDataProvider(maskRef), NULL, false);

    CGImageRef masked = CGImageCreateWithMask([referenceImage CGImage], mask);
    return [UIImage imageWithCGImage:masked];
}

所以,我的形象将是:

myImageView.image = [self maskImage:[UIImage imageNamed:@"image.png"] 
                           withMask:[UIImage imageNamed:@"mask.png"]];

问题: 输出图像与参考图像('image.png')的大小相同,周围有透明区域.但我想避开那些透明区域,并裁剪结果图像.我怎样才能做到这一点？有几个掩模,并且掩模框架与所有掩模框架不相似.我在这里附上问题概述的参考图像.请帮帮我的朋友.提前致谢.

我有这个代码:

 Texture2D *cachedTexture;

if(cachedTexture = [cachedTextures objectForKey:aName]) {
    return cachedTexture;
}

// We are using imageWithContentsOfFile rather than imageNamed, as imageNamed caches the image in the device.
// This can lead to memory issue as we do not have direct control over when it would be released.  Not using
// imageNamed means that it is not cached by the OS and we have control over when it is released.
NSString *filename = [aName stringByDeletingPathExtension];
NSString *filetype = [aName pathExtension];
NSString …