Returns an affine transformation matrix constructed from scaling values you provide.
SDKs
- iOS 2.0+
- macOS 10.0+
- tvOS 9.0+
- watchOS 2.0+
Framework
- Core Graphics
Declaration
CGAffineTransform CGAffineTransformMakeScale(CGFloat sx, CGFloat sy);
Parameters
sx
The factor by which to scale the x-axis of the coordinate system.
sy
The factor by which to scale the y-axis of the coordinate system.
Return Value
A new affine transformation matrix.
Discussion
This function creates a CGAffine
structure, which you can use (and reuse, if you want) to scale a coordinate system. The matrix takes the following form:

Because the third column is always (0,0,1)
, the CGAffine
data structure returned by this function contains values for only the first two columns.
These are the resulting equations used to scale the coordinates of a point (x,y):

If you want only to scale an object to be drawn, it is not necessary to construct an affine transform to do so. The most direct way to scale your drawing is by calling the function CGContext
.