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

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

(declare-type ambient-list structure)
(declare-type collide-list structure)

;; These is the base class for the scene graph node.
;; Note that it doesn't always make sense to call all of these methods on all types,
;; and that certain methods should only be called at certain times, and may require coordination
;; with having certain VU0 or scratchpad data present.
;; In many cases, "draw" simply adds data to a buffer that must later be converted to dma in finish-background
;; or similar.

(declare-type drawable-error drawable)
(deftype drawable (basic)
  ((id      int16          :offset-assert 4)  ;; ID number for visibility (not always used)
   (bsphere vector :inline :offset-assert 16) ;; bounding sphere
   )
  :method-count-assert 18
  :size-assert         #x20
  :flag-assert         #x1200000020
  (:methods
    ;; initialize the drawable after it has been loaded.
    (login (_type_) _type_ 9)
    ;; do some sort of drawing... this really does different things for different types.
    (draw (_type_ _type_ display-frame) none 10)

    ;; add collision meshes to the given collide list if they intersect the bounding box in *collide-work*
    ;; the integer argument can be used to call this method on an inline-array of drawables (only some support this)
    ;; this avoids the dynamic dispatch on each element of the array.
    (collide-with-box (_type_ int collide-list) none 11)

    ;; similar to above, but only add if the collision mesh intersects with a "y probe"
    (collide-y-probe (_type_ int collide-list) none 12)

    ;; similar to above, but only add if the collision mesh intersects a ray of spheres.
    (collide-ray (_type_ int collide-list) none 13)

    ;; different for different types, but generally collects debug statistics like numbers of triangles
    (collect-stats (_type_) none 14)

    ;; different for different types, but usually does nothing.
    (debug-draw (_type_ drawable display-frame) none 15)
    
    ;; given VIS data (uncompressed), compute the visiblity bit string.
    (unpack-vis (_type_ (pointer int8) (pointer int8)) (pointer int8) 16)
    
    ;; find "ambients" inside the given sphere and add to list.
    (collect-ambients (_type_ sphere int ambient-list) none 17)
    )
  )



;; A drawable that simply draws a sphere and an error message at the origin of the bounding sphere.
(deftype drawable-error (drawable)
  ((name    string          :offset-assert 32)
   )
  :method-count-assert 18
  :size-assert         #x24
  :flag-assert         #x1200000024
  )

(declare-type process-drawable process)
(define-extern process-drawable-art-error (state string process-drawable))
(define-extern foreground-engine-execute (function engine display-frame int int none))
(define-extern sphere-in-view-frustum? (function sphere symbol))

(declare-type draw-control basic)
(define-extern add-process-drawable (function process-drawable draw-control symbol dma-buffer none))
(define-extern dma-add-process-drawable-hud (function process-drawable draw-control symbol dma-buffer none))
(define-extern dma-add-process-drawable (function process-drawable draw-control symbol dma-buffer none))
(define-extern vis-cull (function int symbol))

(define-extern line-in-view-frustum? (function vector vector symbol)) ;; TODO - not confirmed