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

;; name: transformq-h.gc
;; name in dgo: transformq-h
;; dgos: GAME, ENGINE

;; the transformq is a transform, but _replaces_ the rotation field with a quaternion.
;; it is much more commonly used than transform.
(deftype transformq (transform)
  ;; this overlays the rot field of transform.
  ((quat  quaternion :inline :offset 16)
   )
  :method-count-assert 9
  :size-assert         #x30
  :flag-assert         #x900000030
  )

;; trsq is the quaternion version of trs (trs is like a transform, but is basic.)
(deftype trsq (trs)
  ;; this overlays the rot field of trs.
  ((quat  quaternion :inline :offset 32)
   )
  :method-count-assert 9
  :size-assert         #x40
  :flag-assert         #x900000040
  )

;; Representing a translate/rotate/scale with a quaternion and a velocity.
;; This is often used as the base type for the position of a game object that can move around
;; so it has methods to do common control functions.
;; many of these functions assume that y is up and assume that roll/pitch is small
;; (a reasonable assumption for most in-game objects that don't do flips)
;; note: Jak's control uses this as a base class.
(deftype trsqv (trsq)
  ((pause-adjust-distance meters             :offset          4)  ;; hack: adjusts the distance where actor logic is paused, if this is an actor
   (nav-radius            meters             :offset          8)  ;; hack: the radius of the bounding sphere used by the navigate system.
   (transv                vector     :inline :offset-assert  64)  ;; velocity (meters/second)
   (rotv                  vector     :inline :offset-assert  80)  ;; angular velocity (deg/second)
   (scalev                vector     :inline :offset-assert  96)  ;; scale velocity (unused?)
   
   ;; there's a hacky ~first-order orientation yaw control with hysteresis
   ;; it makes the yaw change smoothly and attempts to cancel out oscillations from the collision system
   (dir-targ              quaternion :inline :offset-assert 112)  ;; direction target
   (angle-change-time     time-frame              :offset-assert 128)  ;; the time when we change rotation directions
   (old-y-angle-diff      float              :offset-assert 136)  ;; the amount we moved last time
   )
  :method-count-assert 28
  :size-assert         #x8c
  :flag-assert         #x1c0000008c
  (:methods
   (seek-toward-heading-vec! (_type_ vector float time-frame) quaternion 9)
   (set-heading-vec! (_type_ vector) quaternion 10)
   (seek-to-point-toward-point! (_type_ vector float time-frame) quaternion 11)
   (point-toward-point! (_type_ vector) quaternion 12)
   (seek-toward-yaw-angle! (_type_ float float time-frame) quaternion 13)
   (set-yaw-angle-clear-roll-pitch! (_type_ float) quaternion 14)
   (set-roll-to-grav! (_type_ float) quaternion 15)
   (set-roll-to-grav-2! (_type_ float) quaternion 16)
   (rotate-toward-orientation! (_type_ quaternion float float) quaternion 17)
   (set-quaternion! (_type_ quaternion) quaternion 18)
   (set-heading-vec-clear-roll-pitch! (_type_ vector) quaternion 19)
   (point-toward-point-clear-roll-pitch! (_type_ vector) quaternion 20)
   (rot->dir-targ! (_type_) quaternion 21)
   (y-angle (_type_) float 22)
   (global-y-angle-to-point (_type_ vector) float 23)
   (relative-y-angle-to-point (_type_ vector) float 24)
   (roll-relative-to-gravity (_type_) float 25)
   (TODO-RENAME-26 (_type_ int vector float) trsqv 26)
   
   ;; note: child classes can override this method to use a different quaternion
   ;; to represent the "current" orientation for the above methods.
   (get-quaternion (_type_) quaternion 27)
   )
  )

(defmethod global-y-angle-to-point trsqv ((obj trsqv) (arg0 vector))
  "Get the angle in the xy plane from the position of this trsqv to the point arg0."
  (vector-y-angle (vector-! (new 'stack-no-clear 'vector) arg0 (-> obj trans)))
  )

(defmethod relative-y-angle-to-point trsqv ((obj trsqv) (arg0 vector))
  "Get the y angle between the current orientation and arg0."
  (deg-diff
   (y-angle obj)
   (vector-y-angle (vector-! (new 'stack-no-clear 'vector) arg0 (-> obj trans)))
   )
  )