(require scheme/class)


(define insect-view%
    (class object%
        (init-field
            (id 0)
            (from (vector 0 0 0))
            (type 'none))
    
        (field
            (to (vector 0 0 0))
            (from-dir (vector 1 0 0))
            (to-dir (vector 1 0 0))
            (time 0)
            (tick 1))
                
        (define/public (move pos dur)
            (set! from to)
            (set! from-dir to-dir)
            (set! to pos)
            (set! to-dir (vnormalise (vsub from to)))
            (set! time 0)
            (set! tick dur))
        
        (define/public (update t d)
           (set! time (+ time d)))
        
        (super-new)))

;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

(define (add-blendshape key model)
    (let ((b (load-primitive model))
            (pname (string-append "p" (number->string key))))
        (pdata-add pname "v")
        (pdata-index-map!
            (lambda (i p)
                (with-primitive b (pdata-ref "p" i)))
            pname)
        (destroy b)))

(define (set-blendshape key)
    (pdata-copy (string-append "p" (number->string key)) "p"))

(define spider-insect-view%
    (class insect-view%
        (inherit-field from to from-dir to-dir time tick)      
        
        (field
            (root (let ((p (with-state
                (hint-unlit)
                (colour (vector 0 0 0))
                (load-primitive "meshes/spider-1.obj"))))
                (with-primitive p                
                    (pdata-copy "p" "p0")
                    (add-blendshape 1 "meshes/spider-2.obj")
                    (add-blendshape 2 "meshes/spider-3.obj") p)))
            (anim-t 0)
            (anim-d (* 0.2 (rndf)))
            (blendshape 0))
        
        (define/override (update t d)
            (with-primitive root
            
                        (when (> anim-t anim-d)
                            (set! anim-t 0)
                            (set! blendshape (modulo (+ blendshape 1) 3))
                            (set-blendshape blendshape))
            
                        (identity)
                        
                        (let ((h (hermite-tangent from to (vmul from-dir 2) (vmul to-dir 2) (/ time tick))
                               #;(vlerp-tangent from to (/ time tick))))
                            (translate (car h))
                            (concat (maim (vector 0 0 1) (vnormalise (cadr h))))
                        
                        (scale 1)))
            (set! time (+ time d))
            (set! anim-t (+ anim-t d)))
        
        (super-new)))

(clear)
(clear-colour 0.5)
(define s (make-object spider-insect-view% 0 (vector 0 0 0) 'spider))

(define t 0)

(every-frame
    (begin
        (when (> (time) t)
            (set! t (+ (time) 1))
            (send s move (vmul (srndvec) 10) 1))
        (send s update (time) (delta))))