Returns a pixmap with a linear transformation applied.
pmis a pixmap
Ais a non-singular 2×2 real matrix
LinearTransformation(pm, A) returns
pm after the pixels has been moved by the mapping
p ↦ A⋅p with the origin of ℝ² at the centre of
pm. The canvas of the pixmap is not enlarged or shrunk.
A ≔ ❨❨1.2, 0.6❩, ❨0.9, 1.4❩❩
⎛1.2 0.6⎞ ⎝0.9 1.4⎠