;; SCALE-3-BY-3
;; By Peter Reidy
;; Filed as {ERIS}<LISPCORE>TEST>DISPLAY>MATMULT>SCALE-3-BY-3.TEST
;; Syntax: (SCALE-3-BY-3 SX SY &optional RESULT)
;; Function description: returns a 3-by-3 homogeneous scaling transformation that scales by a factor of SX along the X axis and SY along the Y axis.  If RESULT is supplied and is a 3-by-3 single-float matrix, it is set to the function's result.
;; Arguments:
;;	SX SY: real numbers
;;	RESULT: a 3-by-3 single-float matrix.
;;
(do-test-group scale-3-by-3-group
	:before
	(progn
		(il:load? '{eris}<lispcore>test>display>matmult>matmult-test.source)
		(test-setq sample (make-array '(3 3) :initial-contents '((1.0 2.0 3.0)(4.0 5.0 6.0)(7.0 8.0 9.0)) :element-type 'single-float))
	)
	(do-test scale-3-by-3-simple-case
		(matrix-p (il:scale-3-by-3 (randmost) (randmost)) 3)
	)
;;
	(do-test scale-3-by-3-with-result
		(let ((fact1 (randmost)) (fact2 (- (randmost))))
			(and
				(not (equal (2dlist sample) (2dlist (il:scale-3-by-3 fact1 fact2))))  ; before
				(il:scale-3-by-3 fact1 fact2 sample)
				(equal (2dlist sample) (2dlist (il:scale-3-by-3 fact1 fact2)))  ; after
			)
		)
	)
)
END