Normalising CGRect between 0 and 1

Question

What is the best way to normalise CGRect values so that they are between 0 and 1 (unit coordinate system)?

Answer 1

How about this:

CGRect rectToConvert;
NSAffineTransform *n = [NSAffineTransform transform];
[n scaleXBy:rectToConvert.size.width 
        yBy:rectToConvert.size.height];
[n invert];

CGRect normalizedRect;
normalizedRect.origin = [n transformPoint:rectToConvert.origin];
normalizedRect.size   = [n transformSize: rectToConvert.size];

CGPoint anyPointINeedToConvert;
CGPoint convertedPoint = [n transformPoint:anyPointINeedToConvert];

I thinks this makes it a little clearer what's going on and lets you take care of translations in an obvious way, if you have to do them.