[Fluxus] voxels and blobby commits

[Dave Griffiths]

That's what that script does. You can make it into a function if you
like? :)

cheers,

dave

On Tue, 2010-02-02 at 12:15 +0000, evan.raskob [lists] wrote:
> This is great but when do we get the holy grail of poly->voxels?? :)
> 
> 
> 
> 
> On Feb 2, 2010, at 10:04 AM, Dave Griffiths wrote:
> 
> > Hi all,
> >
> > I've added a (voxel->blobby) command to so we can use the marching  
> > cubes
> > meshing algorithm to create polygon solids from voxels. I've also
> > updated the documentation a little for the voxels.
> >
> > I also stumbled across some strange new effects:
> > http://www.pawfal.org/dave/blog/category/accidental-art/
> >
> > Here is a script for converting polygons into voxels - thus completing
> > the circle:
> >
> > (clear)
> > (clear-colour 0.5)
> >
> > ; load the polygon object
> > (define poly (with-state
> >    (scale 2) ; make it fit nicely within the voxels area
> >    (load-primitive "bot.obj")))
> >
> > ; apply the fitting transform
> > (with-primitive poly (apply-transform))
> >
> > ; make some voxels
> > (define v
> >    (with-state
> >        (blend-mode 'src-alpha 'one)
> >        (hint-nozwrite)
> >        (texture (load-texture "splat.png"))
> >        ; move around the polygon object
> >        (scale 8)
> >        (translate (vector -0.5 -0.5 -0.5))
> >        (build-voxels 50 50 50)))
> >
> > ; utils - need to put these somewhere else
> > (define (voxels-index x y z)
> >    (+ x (* y (voxels-width)) (* z (voxels-width) (voxels-height))))
> >
> > (define (voxels-pos i)
> >    (vdiv (vector (modulo i (voxels-width))
> >            (modulo (quotient i (voxels-width)) (voxels-height))
> >            (quotient i (* (voxels-width) (voxels-height)))) (voxels- 
> > width)))
> >
> > ; for each voxel, check for odd or even intersection counts against  
> > the poly
> > (with-primitive v
> >  (pdata-index-map!
> >     (lambda (i c)
> >          (let ((p (vtransform (voxels-pos i) (get-transform))))
> >              (if (odd? (length (with-primitive poly (geo/line- 
> > intersect (vector 0 1 -1000) p))))
> >                    (vector 1 1 1 1) ; inside
> >                    (vector 0 0 0 0)))) ; outside
> >        "c")
> >    ; the rest of this is to make it look pretty for previewing
> >    (voxels-calc-gradient)
> >    (pdata-copy "g" "c")
> >    (pdata-map!
> >        (lambda (c)
> >            (if (< (vmag c) 0.1)
> >                (vector 0 0 0 0) c))
> >        "c"))
> >
> > (destroy poly)
> >
> > ; convert to a blobby
> > (define bp
> >    (with-state
> >        (hint-unlit) ; again all this
> >        (colour 1)   ; just for
> >        (hint-wire)  ; preview rendering
> >        (voxels->blobby v)))
> > (destroy v)
> >
> > (define pp (blobby->poly bp))
> > (destroy bp)
> >
> > (with-primitive pp
> >    (recalc-normals 1))
> >
> >
> >
>