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

;; This file demonstrates how to use the debug draw.

;; To run this:

#|
(make-group "iso")  ;; build the game
(lt)                ;; connect to the runtime
(lg)                ;; have the runtime load the game engine
(test-play)         ;; start the game loop
(ml "goal_src/examples/debug-draw-example.gc")  ;; build and load this file.
|#

(defun hack-update-camera ((location vector) (inv-rot matrix))
  "Debugging function to set the camera's position and orientation"
  ;; update to compute the perspective matrix.
  (update-math-camera
    *math-camera*
    (-> *setting-control* current video-mode)
    (-> *setting-control* current aspect-ratio)
    )
  
  ;; copy the input rotation
  (matrix-copy! (-> *math-camera* inv-camera-rot) inv-rot)
  ;; inverse of rotation matrix matrix is its transpose
  (matrix-transpose! (-> *math-camera* camera-rot) (-> *math-camera* inv-camera-rot))
  
  ;; fake some value here
  (set! (-> *math-camera* fov-correction-factor) 1.0)
  
  ;; do the math
  (set! (-> *math-camera* trans quad) (-> location quad))
  (let ((cam-temp (-> *math-camera* camera-temp))
        (cam-rot (-> *math-camera* camera-rot))
        (inv-cam-rot (-> *math-camera* inv-camera-rot))
        (cam-trans (-> *math-camera* trans))
        )
    (let ((rotated-trans (new-stack-vector0)))
      (set! (-> rotated-trans x) (- (-> cam-trans x)))
      (set! (-> rotated-trans y) (- (-> cam-trans y)))
      (set! (-> rotated-trans z) (- (-> cam-trans z)))
      (set! (-> rotated-trans w) 1.0)
      (vector-matrix*! rotated-trans rotated-trans cam-rot)
      (set! (-> cam-rot vector 3 quad) (-> rotated-trans quad))
      )
    (matrix*! cam-temp cam-rot (-> *math-camera* perspective))
    (set! (-> inv-cam-rot vector 3 quad) (-> cam-trans quad))
    )
  
  (none)
  )

(defun test-function ((iter int))
  "This function draws the debug stuff. You can edit this, then reload this file to play with it."

  ;; val will increase from 0 to 1, then reset back to 0.
  (let* ((frame (the float (mod (* 4 iter) 1600)))
         (val (/ frame 1600.0)))
    (format *stdcon* "~0kval ~f~%" val)

    ;; orbit the camera around in a circle with radius 5 m.
    (let* ((rad (meters 5.0))
           (x (* rad (sin (* (degrees 360.0) val))))
           (z (* rad (cos (* (degrees 360.0) val))))
           (cam-pos (new 'stack 'vector))
           (cam-inv-rot (new 'stack 'matrix))
           )
      ;; this matrix will look directly at the origin...
      (set! (-> cam-pos x) x)
      (set! (-> cam-pos z) z)
      (set! (-> cam-pos y) (meters 2.))
      (forward-down->inv-matrix cam-inv-rot cam-pos (new 'static 'vector :y 1.0))

      ;; if the camera is here.
      (set! (-> cam-pos x) (- 0. x))
      (set! (-> cam-pos z) (- 0. z))
      (set! (-> cam-pos y) (meters -2.))
      (hack-update-camera cam-pos cam-inv-rot)
      
      
      ;; create some test points
      (let ((p0 (new 'static 'vector :x (meters .8) :y (meters .2) :z (meters 2.0)))
            (p1 (new 'static 'vector :x (meters .3) :y (meters .3) :z (meters 2.5)))
            (p2 (new 'static 'vector :x (meters .5) :y (meters .7) :z (meters 1.5)))
            )
            
        ;;(add-debug-point #t (bucket-id debug-draw0) (new 'static 'vector))
        (add-debug-x #t (bucket-id debug-draw0) (new 'static 'vector) (new 'static 'rgba :g #x80 :a #x80))
        (add-debug-box #t (bucket-id debug-draw0) p0 p2 (new 'static 'rgba :b #x80 :a #x80))
        (add-debug-flat-triangle #t (bucket-id debug-draw0) p0 p1 p2 (new 'static 'rgba :r #x80))
        (add-debug-text-3d #t (bucket-id debug-draw0) "triangle!" p0 (font-color yellow-green) (the vector2h #f))
        (add-debug-sphere #t (bucket-id debug-draw0) p2 (meters 0.5) (new 'static 'rgba :r #x80))
        )
      )

    ;; these also work
    ;; (draw-end-credits (the int frame))
    ;; (draw-title-credits val)

    )
  (none)
  )


(defun launch-test-process ()
  "Call this to launch a process that draws the debug demo"
  (let ((proc (get-process *nk-dead-pool* process 1024)))
    (activate proc *active-pool* 'test *kernel-dram-stack*)
    (run-next-time-in-process proc (lambda ()
                                     (let ((iter 0))
                                       (while #t
                                         (test-function iter)
                                         (suspend)
                                         (+! iter 1)
                                         )
                                       )
                                     )
                              )
    proc)

  )

;; This will spawn a process the first time this file is loaded
(define-perm *test-process* process (launch-test-process))

(defun kill-test-procs ()
  "Kill all processes started by launch-test-process"
  (kill-by-name "test" *active-pool*)
  )

(set! *display-profile* #t)