;;
;; Procedures for rotating, scaling, translating points.
;; Based on the Python GTS library.
;;

(define (point-translate p #!key (dx 0.0) (dy 0.0) (dz 0.0))
  (let ((v (f64vector dx dy dz)))
    (let ((m (matrix-translate #f v)))
      (point-transform p m)
      (matrix-destroy m)
      p)))


(define (point-scale p #!key (dx 0.0) (dy 0.0) (dz 0.0))
  (let ((v (f64vector dx dy dz)))
    (let ((m (matrix-scale #f v)))
      (point-transform p m)
      (matrix-destroy m)
      p)))


(define (point-rotate p #!key (dx 0.0) (dy 0.0) (dz 0.0) (angle 0.0))
  (let ((v (f64vector dx dy dz)))
    (let ((m (matrix-rotate #f v angle)))
      (point-transform p m)
      (matrix-destroy m)
      p)))