CGAffineTransform的使用

typedef struct CGAffineTransform CGAffineTransform;

struct CGAffineTransform {

CGFloat a, b, c, d;

CGFloat tx, ty;

};

const CGAffineTransform CGAffineTransformIdentity；

CGAffineTransform CGAffineTransformMake(CGFloat a, CGFloat b,

CGFloat c, CGFloat d, CGFloat tx, CGFloat ty)；

CGAffineTransform CGAffineTransformMakeTranslation(CGFloat tx,

CGFloat ty) ;

//大小变化

CGAffineTransform CGAffineTransformMakeScale(CGFloat sx, CGFloat sy)；

//旋转

CGAffineTransform CGAffineTransformMakeRotation(CGFloat angle)；

bool CGAffineTransformIsIdentity(CGAffineTransform t)；

CGAffineTransform CGAffineTransformTranslate(CGAffineTransform t,

CGFloat tx, CGFloat ty)；

//在t的基础上放大变化

CGAffineTransform CGAffineTransformScale(CGAffineTransform t,

CGFloat sx, CGFloat sy) ；

CGAffineTransform CGAffineTransformInvert(CGAffineTransform t)；

CGAffineTransform CGAffineTransformConcat(CGAffineTransform t1,

CGAffineTransform t2)；

bool CGAffineTransformEqualToTransform(CGAffineTransform t1,

CGAffineTransform t2)；

CGPoint CGPointApplyAffineTransform(CGPoint point,

CGAffineTransform t)；

GSize CGSizeApplyAffineTransform(CGSize size, CGAffineTransform t)；

CGRect CGRectApplyAffineTransform(CGRect rect, CGAffineTransform t)；