Question

I would like to draw on a CGContext by using tiles from CGImage that I would like to draw in a specified order.

According to documentation here it seems that the only method to draw an image in a graphic context is

void CGContextDrawImage (
   CGContextRef c,
   CGRect rect,
   CGImageRef image
);

But this doesn’t take in account the case in which I want to draw just a CGRect of the source image. Do I have to do some tricks to make this work?

Answer 1

If I understand your question correctly then you are asking to crop an image at a particular CGRect, if so then you need to take a look at this method.

CGImageCreateWithImageInRect(CGImage image, CGRect rect)

This will return you a CGImageRef and according to your need I think this is what you are looking for.