Q:

How do I remove those rotation artefacts from my CATiledLayer?

I have a CATiledLayer into which I render content in the following method
- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx

I used the QuartzDemo code to draw a pattern. This works very well until I apply a rotation transform to the layer's parentLayer (a UIView):

rotated:

These zigzag artefacts become worse when I start drawing lines and texts into the CATiledLayer.
I applied the transform as follows (I also tried using an affine transform on the view itself):
self.containerView.layer.transform = CATransform3DMakeRotation(angleRadians, 0.0f, 0.0f, 1.0f);

I transform the containerView rather than the layer itself, as I have several layers in that view that I would like to rotate at the same time without changing the relative positions.
I did not have problems when rotating UIImageViews in the past.
Is there a way that I can rotate the CATiledLayer without these problems?
Any help would be greatly appreciated.
Yours,
Felix

A:

The only way of fixing this issue I found was this:

Draw the layer into a bitmap context
Set the CGImageRef of that context as the layer contents 

