;;-*-Lisp-*-
(in-package goal)

;; name: transform.gc
;; name in dgo: transform
;; dgos: ENGINE, GAME

;; DECOMP BEGINS

(defmethod print transform ((obj transform))
  "Print a transform."
  (format #t "#<transform @ #x~X~%" obj)
  (format #t "~T~Ttrans:~F ~F ~F ~F ~%" (-> obj trans x) (-> obj trans y) (-> obj trans z) (-> obj trans w))
  (format #t "~T~Trot:  ~F ~F ~F ~F ~%" (-> obj rot x) (-> obj rot y) (-> obj rot z) (-> obj rot w))
  (format #t "~T~Tscale:~F ~F ~F ~F>" (-> obj scale x) (-> obj scale y) (-> obj scale z) (-> obj scale w))
  obj
  )

(defmethod new trs ((allocation symbol) (type-to-make type))
  "Allocate a new transform and set to identity."
  (let ((gp-0 (object-new allocation type-to-make (the-as int (-> type-to-make size)))))
    (set! (-> gp-0 trans w) 1.0)
    (set! (-> gp-0 rot w) 1.0)
    (vector-identity! (-> gp-0 scale))
    gp-0
    )
  )

;;;;;;;;;;;;;;;;;;;;;;;;;;
;; transform utilities
;;;;;;;;;;;;;;;;;;;;;;;;;;

;; these functions are unused and possibly extremely old.
;; they aren't very efficient, and have the destination as the 2nd argument,
;; which differens from almost all other GOAL code.

(defun transform-matrix-calc! ((arg0 transform) (arg1 matrix))
  "Convert a transform to matrix. Not efficient, and the output is the second arg."
  (let ((s4-0 (new-stack-matrix0))
        (s3-0 (new-stack-matrix0))
        )
    (matrix-identity! arg1)
    (matrix-translate! arg1 (-> arg0 trans))
    (matrix-rotate-y! s4-0 (-> arg0 rot y))
    (matrix*! s3-0 s4-0 arg1)
    (matrix-rotate-x! s4-0 (-> arg0 rot x))
    (matrix*! arg1 s4-0 s3-0)
    (matrix-rotate-z! s4-0 (-> arg0 rot z))
    (matrix*! s3-0 s4-0 arg1)
    (matrix-scale! s4-0 (-> arg0 scale))
    (matrix*! arg1 s4-0 s3-0)
    )
  )

(defun transform-matrix-parent-calc! ((arg0 transform) (arg1 matrix) (arg2 vector))
  "Convert a transform to a matrix, applying an inverse scaling."
  (let ((s4-0 (new-stack-matrix0))
        (s3-0 (new-stack-matrix0))
        )
    (matrix-identity! s3-0)
    (matrix-translate! s3-0 (-> arg0 trans))
    (matrix-inv-scale! s4-0 arg2)
    (matrix*! arg1 s4-0 s3-0)
    (matrix-rotate-y! s4-0 (-> arg0 rot y))
    (matrix*! s3-0 s4-0 arg1)
    (matrix-rotate-x! s4-0 (-> arg0 rot x))
    (matrix*! arg1 s4-0 s3-0)
    (matrix-rotate-z! s4-0 (-> arg0 rot z))
    (matrix*! s3-0 s4-0 arg1)
    (matrix-scale! s4-0 (-> arg0 scale))
    (matrix*! arg1 s4-0 s3-0)
    )
  )

(defun trs-matrix-calc! ((arg0 trs) (arg1 matrix))
  "Convert a trs to a matrix"
  ;; this relies on the fact that trs and transform both have the same memory layout.
  (transform-matrix-calc! (the-as transform (-> arg0 trans)) arg1)
  )