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
sxThe factor by which to scale the x-axis of the coordinate system.
syThe 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.