Courses/CS 461/Winter 2006/Rick Strom/Week One/HW1 - Water

From CSWiki

;; stromwater.nlogo
;; by Rick Strom
;;
;; a 2D water simulation (ripples)
;; see Information tab for info on this

patches-own [ height  
              prev-height
              next-height ]
              
globals [ x y ]

to setup
  ca
  ask patches [
    set height 0
    set next-height 0
    set prev-height 0
    set pcolor height + 93
  ] 
end

to go
  if continuous-drops [ add-drop ]

  ask patches [
    ; calculate the next-height values
    set next-height (
      (((
        height-of patch-at   0  1 + 
        height-of patch-at   1  0 + 
        height-of patch-at   0 -1 +
        height-of patch-at  -1  0 
      ) / 2) - prev-height) * damping
    )      
  ]
  
  ask patches [
   ; copy over next-height values
   set prev-height height
   set height next-height
   set pcolor height + 93
  ]
end

to add-drop
 ; we just randomly choose a patch and set its value to 100 (white-blue)
 set x random(2 * screen-edge-x) - screen-edge-x
 set y random(2 * screen-edge-y) - screen-edge-y 
 
 set height-of patch-at x y 20
 set pcolor-of patch-at x y height-of patch-at x y + 93
end