cairoMatrixTransformDistance: cairoMatrixTransformDistance
In RGtk2: R Bindings for Gtk 2.8.0 and Above

Description Usage Arguments Details Author(s)

Transforms the distance vector (dx,dy) by matrix. This is similar to cairoMatrixTransformPoint except that the translation components of the transformation are ignored. The calculation of the returned vector is as follows:

1	cairoMatrixTransformDistance(matrix, dx, dy)

`matrix`	[`CairoMatrix`] a `CairoMatrix`
`dx`	[numeric] X component of a distance vector. An in/out parameter
`dy`	[numeric] Y component of a distance vector. An in/out parameter

1 2	dx2 = dx1 * a + dy1 * c; dy2 = dx1 * b + dy1 * d;

Affine transformations are position invariant, so the same vector always transforms to the same vector. If (x1,y1) transforms to (x2,y2) then (x1+dx1,y1+dy1) will transform to (x1+dx2,y1+dy2) for all values of x1 and x2.