SkewRotation
Returns a pixmap with each row of pixels rotated an amount that is proportional to its position.
Syntax

SkewRotation(pm, a[, b[, d]])

pm
is a pixmap 
a
andb
are integers 
d
is either"h"
or"v"

Description
SkewRotation(pm, x, d)
returns pm
with each row (if d = "h"
) or column (if d = "v"
) of pixels rotated trunc(i⋅a/b)
pixels, where i
is the position of the row or column. If omitted, b
defaults to 100
and d
to "h"
.
Examples
SkewRotation(ExampleData("Sally"), 20)