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

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

;; The "drawable tree" represents a BVH for a specific render.
;; Typically, levels will have ~10 drawable trees.  There will be a tree for
;; tfrag, a tree for actors, a tree for tie,

;; This file contains common functions for all drawable trees.

(defmethod draw drawable-tree-array ((obj drawable-tree-array) (arg0 drawable-tree-array) (arg1 display-frame))
  "Draw a drawable tree array. If the current level is set to special or special-vis, the draw is skipped."
  (let ((v1-1 (-> (scratchpad-object terrain-context) bsp lev-index)))
    (case (-> *level* level v1-1 display?)
          (('special 'special-vis #f)
           )
          (else
            (dotimes (s3-0 (-> obj length))
              (draw (-> obj trees s3-0) (-> arg0 trees s3-0) arg1)
              )
            )
          )
    )
  0
  (none)
  )

(defmethod collect-stats drawable-tree-array ((obj drawable-tree-array))
  (dotimes (s5-0 (-> obj length))
    (collect-stats (-> obj trees s5-0))
    )
  (none)
  )

(defmethod debug-draw drawable-tree-array ((obj drawable-tree-array) (arg0 drawable) (arg1 display-frame))
  (dotimes (s3-0 (-> obj length))
    (debug-draw (-> obj trees s3-0) (-> (the-as drawable-tree-array arg0) trees s3-0) arg1)
    )
  (none)
  )

(defmethod unpack-vis drawable-tree ((obj drawable-tree) (arg0 (pointer int8)) (arg1 (pointer int8)))
  "Copy our visibility data from arg1 to arg0, unpacking it."
  (local-vars (t5-1 int))
  
  ;; grab the first array
  (let* ((v1-0 (the-as drawable-inline-array-node (-> obj data 0)))
         ;; first elt in top array
         (a3-1 (/ (-> v1-0 data 0 id) 8))
         ;; number in first array (8 or fewer)
         (t0-0 (-> v1-0 length))
         ;; offset in destination
         (v1-1 (&+ arg0 a3-1))
         ;; number of bytes
         (a3-3 (/ (+ t0-0 7) 8))
         )
    ;; copy the data!
    ;;(mem-print (the (pointer uint32) arg1) 10)
    (dotimes (t0-1 a3-3)
      (let ((t1-0 (-> arg1 0)))
        ;;(format 0 "top-copy: #x~X~%" t1-0)
        (set! arg1 (&-> arg1 1))
        (set! (-> v1-1 0) t1-0)
        )
      (set! v1-1 (&-> v1-1 1))
      )
    )
  ;; now, the remaining arrays, excluding the final which isn't a draw node array.
  (let ((v1-5 (+ (-> obj length) -1)))
    (when (nonzero? v1-5)
      (dotimes (a3-5 v1-5)
        ;; pointer to this array
        (let* ((t0-4 (-> obj data a3-5))
               ;; pointer to next depth array
               (t2-0 (-> obj data (+ a3-5 1)))
               ;; id of first in prev
               (t1-5 (/ (-> (the-as drawable-inline-array-node t0-4) data 0 id) 8))
               ;; id of first in next
               (t2-2 (/ (-> (the-as drawable-inline-array-node t2-0) data 0 id) 8))
               ;; number of nodes in this one
               (t0-5 (-> (the-as drawable-inline-array-node t0-4) length))
               ;; output for prev level
               (t1-6 (&+ arg0 t1-5))
               ;; output for next level
               (t2-3 (&+ arg0 t2-2))
               )
          (while #t
            ;; load the vis byte for the one in this array
            (let ((t3-0 (-> t1-6 0)))
              ;; inc vis ptr.
              (set! t1-6 (&-> t1-6 1))
              ;; vis mask bit. (init at highest)
              (let ((t4-0 128))
                (label cfg-7)
                ;; check if we're visible
                (b! (zero? (logand t3-0 t4-0)) cfg-9 :delay (set! t5-1 (-> arg1 0)))
                ;; we are visible. write 8 in the output
                (set! arg1 (&-> arg1 1))
                (set! (-> t2-3 0) t5-1)
                (label cfg-9)
                (+! t0-5 -1)
                ;; check if we've done all nodes
                (b! (zero? t0-5) cfg-12 :delay (.sra t4-0 t4-0 1))
                ;; check if we're done with this byte and inc output.
                (b! (nonzero? t4-0) cfg-7 :delay (set! t2-3 (&-> t2-3 1)))
                )
              )
            )
          )
        (label cfg-12)
        (nop!)
        0
        )
      )
    )
  arg1
  )