How to figure out if two CGRect intersect?

In -drawRect: I want to check if the provided rect intersects with anotherRect.

I'm not good at this geometry math stuff and especially at english so what I want to say is:

If y开发者_如何学Pythonou have two sheets of paper on the desk, and one of them covers the other either completely or just a small portion, it is rectsIntersect = YES.

How to check that out for rect and anotherRect?

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Use bool CGRectIntersectsRect (CGRect rect1,CGRect rect2);

Swift 3:

public func intersects(_ rect2: CGRect) -> Bool

Example: rect1.intersects(rect2)

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Try to use this.. While animating imageview you can get its actual frame by this:

[[obstacle1.layer presentationLayer] frame];

So, it will easily to make collision of two imageview

if (CGRectIntersectsRect([[obstacle1.layer presentationLayer] frame], [[bgImageView.layer
    presentationLayer] frame])) 
{

    NSLog(@"Collision 1");

}