load-opengl
300 dup display 2d animation

variable points
variable mask-matrix

: reset
  (( 1 -1)
   ( 1  1)
#   (-1  1)
   (-1 -1)) >matrix points ! ;

	 


: mask
   1 pack >matrix
   dup matrix:average 1. swap / *
   mask-matrix ! ;

(1 3 3 1)      # fractal..
mask reset

# the mask above gives irregular patterns.  in "Wavelets on Irregular
# Point Sets" by Ingrid Daubechies, Igor Guskov, Peter Schroeder and
# Wim Sweldens, i found i found (-1 9 9 -1), which does give smooth
# grids. 

# http://cm.bell-labs.com/who/wim/papers/royal/

: x
	points @
	  dup mask-matrix @ matrix:fir
	  matrix:interlace
	points ! ;

: drawit
    .3 scale
    points @ 1 pack "v" lineloop ;

' drawit is drawer


: randomize
	points @ matrix:normal points ! ;

: confused 
    reset
    (-1 9 9 -1) mask
    x x x x x x x x x x x x x
    randomize
    x x x x x
    .3 points *!
 ;
    


interactive