groworld/plant-eyes/extrude.scm
2009-07-09 12:52:56 +01:00

185 lines
No EOL
6.4 KiB
Scheme

;#lang scheme
;(require fluxus-016/drflux)
; extrusion code
(define (draw-profile index profile offset)
(cond ((not (null? profile))
(pdata-set! "p" index (vadd (car profile) offset))
(draw-profile (+ index 1) (cdr profile) offset))))
(define (transform-profile profile m)
(cond
((null? profile) '())
(else
(cons (vtransform (car profile) m)
(transform-profile (cdr profile) m)))))
; figures out the vector for rotation of the profile
(define (path-vector first-segment path lv)
(let* ((v (if (null? (cdr path)) ; last segment?
lv ; use the last vector used
(vsub (cadr path) (car path)))) ; use the next point
(vd (if first-segment v ; first segment?
(vadd (vmul lv 0.5) ; blend with the last vector
(vmul v 0.5)))))
vd))
(define (extrude-segment index profile path width lv up size)
(cond ((not (null? path))
(let ((v (path-vector (zero? index) path lv)))
(draw-profile index (transform-profile profile
(mmul
(maim v up)
(mrotate (vector 0 90 0))
(mscale (vmul (vector (car width) (car width) (car width)) size))))
(car path))
v))))
(define (extrude index profile path width lv up)
(cond ((not (null? path))
(let ((v (extrude-segment index profile path width lv up 1)))
(extrude (+ index (length profile)) profile (cdr path) (cdr width) v up)))))
(define (stitch-face index count profile-size in)
(cond
((eq? 1 count)
(append in (list (+ (- index profile-size) 1) index (+ index profile-size)
(+ (- index profile-size) 1 profile-size))))
(else
(append
(list (+ index 1) index
(+ index profile-size) (+ index profile-size 1))
(stitch-face (+ index 1) (- count 1) profile-size in)))))
(define (stitch-indices index profile-size path-size in)
(cond
((eq? 1 path-size) in)
(else
(append
(stitch-face index profile-size profile-size '())
(stitch-indices (+ index profile-size)
profile-size
(- path-size 1)
in)))))
(define (build-tex-coords profile-size path-size vscale)
(pdata-index-map!
(lambda (i t)
(vector (* vscale (/ (quotient i profile-size) path-size))
(/ (modulo i profile-size) profile-size) 0))
"t"))
(define (build-extrusion profile path width tex-vscale up)
(let ((p (build-polygons (* (length profile) (length path)) 'quad-list)))
(with-primitive p
(poly-set-index (stitch-indices 0 (length profile) (length path) '()))
(build-tex-coords (length profile) (length path) tex-vscale)
(extrude 0 profile path width (vector 0 0 0) up)
(recalc-normals 0))
p))
; partial extrusions are for animating
(define (build-partial-extrusion profile path tex-vscale)
(let ((p (build-polygons (* (length profile) (length path)) 'quad-list)))
(with-primitive p
(poly-set-index (stitch-indices 0 (length profile) (length path) '()))
(build-tex-coords (length profile) (length path) tex-vscale))
p))
(define (partial-extrude t profile path width up grow)
(define (chop-front l n)
(cond ((null? l) l)
(else
(if (zero? n) (cons (car l) (chop-front (cdr l) n))
(chop-front (cdr l) (- n 1))))))
(define (collapse-front)
(let ((start (* (floor t) (length profile))))
(for ((i (in-range (+ start (* (length profile) 1)) (pdata-size))))
(pdata-set! "p" i (pdata-ref "p" start)))))
(define (scale-front)
(when (> t 1)
(let* ((start (* (floor t) (length profile)))
(from (list-ref path (- (inexact->exact (floor t)) 1)))
(to (list-ref path (+ (inexact->exact (floor t)) 0))))
(for ((i (in-range start (+ start (length profile)))))
(pdata-set! "p" i (vmix to from (- t (floor t))))))))
(define (_ t v g)
(cond
((< t 1) (with-primitive p (recalc-normals 0)) v)
(else
(let ((start (* (floor t) (length profile))))
(_ (- t 1)
(extrude-segment start profile
(chop-front path (floor t))
(chop-front width (floor t)) v up
(if (< g 1)
(+ g (* (- t (floor t)) grow))
g))
(if (< g 1)
(+ g grow)
1))))))
(_ t (vector 0 0 0) 0)
(scale-front)
(collapse-front))
(define (build-circle-profile n r)
(define (_ n c l)
(cond ((zero? c) l)
(else
(let ((a (* (/ c n) (* 2 3.141))))
(_ n (- c 1)
(cons (vmul (vector (sin a) (cos a) 0) r) l))))))
(_ n n '()))
(clear)
(clear-colour 0.5)
(define profile (build-circle-profile 12 0.5))
(define width (build-list 100
(lambda (n) (* n 0.01 (+ 1.5 (cos (* 0.5 n)))))))
(define path (build-list 100
(lambda (n) (vmul (vector (sin (* 0.2 n)) 0 (cos (* 0.2 n))) (* 0.05 n)))))
(define p (with-state
(wire-colour 0)
; (colour (vector 0.5 0.3 0.2))
(colour (vector 1 1 1))
(specular (vector 1 1 1))
(shinyness 20)
(hint-wire)
(texture (load-texture "textures/root.png"))
(build-partial-extrusion profile path 10)))
#;(with-state
(wire-opacity 0.4)
(translate (vector 0 0 0))
(wire-colour (vector 0 0 1))
(hint-none)
(hint-wire)
; (hint-normal)
(backfacecull 1)
(point-width 5)
(build-extrusion profile path width 1 (vector 0 1 0)))
(define t 0)
(define (animate)
(with-primitive p
(partial-extrude
(* (* 0.5 (+ 1 (sin (* 0.2 t)))) (length path))
profile path width (vector 0 1 0) 0.05)
(set! t (+ t 0.01))))
(every-frame (animate))
(end-framedump)
;(start-framedump "ext-" "jpg")