[Fluxus] what about procedural textures on fluxus?

[Dave Griffiths]

On Wed, 2007-10-31 at 22:41 -0300, Glauber Alex Dias Prado wrote:
> Hey Dave i was thinking here what about some basic procedural textures
> with fluxus? perhaps something like noise, bands this sort of thing
> extended trough scheme? would be good not to rely on gimp for all sort
> of textures isnt? what do you think about? maybe the glsl shader already
> got everything and my point is missing? I would like to know your ideas
> about it as you certainly has thinked about this a lot, you can answer
> to me on the list if you feel like it.

They are not widely advertised, but you can use pixel-primitives for
this. You'll need to get cvs to run this script as I tried it in the new
style (tm) and had to add pdata-index-map! (and pdata-index-fold) which
supply the pdata element index to the first argument of the procedure:

(clear)

(with-state

	;; simple random noise
    (with-primitive (build-pixels 100 100)
        (pdata-map! 
            (lambda (colour)
                (vector (flxrnd) 0 0 1))
            "c")
        (pixels-upload))
    
    (translate (vector 1.2 0 0))
    
	;; colourful stripes
    (with-primitive (build-pixels 100 100)
        (pdata-index-map! 
            (lambda (index colour)
                (vector (/ (modulo index 10) 10)
                        (/ (modulo index 50) 50) 
                        (/ (modulo index 20) 20) 1))
            "c")
        (pixels-upload))
    
    (translate (vector 1.2 0 0))
    
	;; b/w stripes
    (with-primitive (build-pixels 100 100)
        (pdata-index-map! 
            (lambda (index colour)
                (let ((v (floor (/ (modulo index 20) 10))))
                    (vector v v v 1)))
            "c")
        (pixels-upload))
)

(translate (vector 0 1.2 0))

(with-state

	;; colourful circles
    (with-primitive (build-pixels 100 100)
        (pdata-index-map! 
            (lambda (index colour)
                (let* ((x (quotient index 100)) 
                       (y (remainder index 100))
                       (d (vdist (vector 50 50 0) (vector x y 0))))
                    (vector (sin d) (cos d) 1)))
            "c")
        (pixels-upload))


    (translate (vector 1.2 0 0))

	;; b/w circles
    (with-primitive (build-pixels 100 100)
        (pdata-index-map! 
            (lambda (index colour)
                (let* ((x (quotient index 100)) 
                       (y (remainder index 100))
                       (d (vdist (vector 50 50 0) (vector x y 0)))
                       (v (floor (* 2 (sin (* d 0.3))))))
                    (vector v v v)))
            "c")
        (pixels-upload))


    (translate (vector 1.2 0 0))

	;; psychedelic mess
    (with-primitive (build-pixels 100 100)
        (pdata-index-map! 
            (lambda (index colour)
                (let* ((x (quotient index 100)) 
                       (y (remainder index 100))
                       (d (vdist (vector 50 50 0) (vector x y 0)))
                       (r (* (sin d) (cos (* y 0.5))))
                       (g (* (sin d) (cos (* x 0.3))))
                       (b (* (sin d) (cos (* y 0.2)))))

                    (vector r g b)))
            "c")
        (pixels-upload))


)