Question

I have an CGFloat property and sometimes I get a return value of type Float64 or also of type Float32. Could I store both safely to CGFloat?

Answer 1

From the headers:

// CGBase.h
typedef float CGFloat;

// MacTypes.h
typedef float               Float32;
typedef double              Float64;

So CGFloat and Float32 are both floats while Float64 is a double so you would lose precision.

(Edit to clarify: this is for 32 bit systems such as the iPhone. If you are building for 64 bit, CGFloat is defined as a double.)