CGRectMake

1     /* Points. */  
2  
3     struct CGPoint {  
4       CGFloat x;  
5       CGFloat y;  
6     };  
7     typedef struct CGPoint CGPoint; 

1 　　/* Sizes. */  
2   
3 　　struct CGSize {  
4   　　CGFloat width;  
5  　　 CGFloat height;  
6 　　};  
7　　 typedef struct CGSize CGSize

1    /* Rectangles. */  
2       
3     struct CGRect {  
4       CGPoint origin;//偏移是相对父窗口的  
5       CGSize size;  
6     };  
7     typedef struct CGRect CGRect;

1     CG_INLINE CGRect  
2     CGRectMake(CGFloat x, CGFloat y, CGFloat width, CGFloat height)  
3     {  
4       CGRect rect;  
5       rect.origin.x = x; rect.origin.y = y;  
6       rect.size.width = width; rect.size.height = height;  
7       return rect;  
8     }