transform-painter fails on non-rectangle configuration

[i@…]

As mentioned in the bible:

(define squash-inwards

(transform-painter (make-vect 0 0)

(make-vect 0.65 0.35)
(make-vect 0.35 0.65)))

(paint (squash-inwards einstein))

this tries to paint einstein in a parallelogram, but DrRacket? complains "vector-ref: expects a vector as 1st argument, given 0"