使用CATransform3DRotate时的反混叠线

Question

我将答案中的代码复制到如何将透视图转换应用于UIView？，以获得以下图像。但是，请注意，将级别分隔开的锯齿状线条。有没有其他方式来执行这种透视图转换，以反别名这些锯齿状的线条？

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编辑我尝试过DarkDust在这篇文章的评论中提供的解决方案。似乎都没有用。这是我的密码：

    levelView = [[UIControl alloc] initWithFrame:CGRectMake(100, 60, 160, 230)];
    [self addSubview:levelView];
    levelView.transform = CGAffineTransformScale(self.transform, .8, .8);

    CALayer *layer = levelView.layer;

    //DarkDust's 2nd comment
    layer.borderWidth = 1;
    layer.borderColor = [[UIColor clearColor] CGColor];

    CATransform3D rotationAndPerspectiveTransform = CATransform3DIdentity;
    rotationAndPerspectiveTransform.m34 = 1.0 / 1000;
    rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform, 45.0f * M_PI / 180.0f, 0.0f, 1.0f, 0.0f);
    layer.transform = rotationAndPerspectiveTransform;

    for (NSString *ID in [NSArray arrayWithObjects:@"Level 1", @"Level 2", @"Level 3", @"Level 4", @"Level 5", nil]) {

        //Note the offset of 5 from the superview in both X and Y directions. This addresses DarkDusk's first comment
        UIControl *ctrl = [[UIControl alloc] initWithFrame:CGRectMake(5, y + 5, levelView.frame.size.width, 220/5)];
        [levelView addSubview:ctrl];
        [ctrl addTarget:self action:@selector(languageSelected:) forControlEvents:UIControlEventTouchDown];
        [self styleEnabled:ctrl];            

        UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(13, 0, ctrl.frame.size.width - 13, ctrl.frame.size.height)];
        [ctrl addSubview:label];
        label.text = ID;
        label.font = [UIFont systemFontOfSize:20];
        label.textColor = [UIColor colorWithRed:1 green:1 blue:1 alpha:.8];
        label.backgroundColor = [UIColor clearColor];

        y += ctrl.frame.size.height;
    }

在图像中看到的级别按钮都是UIControl的实例，它们是UIControl *levelView的直接子视图。levelView是一个正在被改变的。

DarkDusk的另外两个评论特别提到了UIImages，我没有使用它。如果它们仍然适用，并且有人可以解释如何实现它们，我肯定会给它们一个机会。

Answer 1

iOS 7为CALayer带来了一个新的属性allowsEdgeAntialiasing，您可以看到这里。当设置为YES时，您的图层将使用反锯齿边缘进行转换.

/* When true this layer is allowed to antialias its edges, as requested
 * by the value of the edgeAntialiasingMask property.
 *
 * The default value is read from the boolean UIViewEdgeAntialiasing
 * property in the main bundle's Info.plist. If no value is found in
 * the Info.plist the default value is NO. */

@property BOOL allowsEdgeAntialiasing;