Subversion Repositories Kolibri OS

--BRUSH Scene: Amigaball 1.0

--

--Draws the famous 'Amiga ball' in the brush.

--

--by Richard Fhager

--http://hem.fyristorg.com/dawnbringer/

-- Copyright 2010 Richard Fhager

--

-- This program is free software; you can redistribute it and/or

-- modify it under the terms of the GNU General Public License

-- as published by the Free Software Foundation; version 2

-- of the License. See 

-- This script was adopted from Evalion, a Javascript codecrafting/imageprocessing project

--http://goto.glocalnet.net/richard_fhager/evalion/evalion.html

w, h = getbrushsize()

if (w<64 or h<64) then

  setbrushsize(64,64)

  w=64

  h=64

end

for y = 0, h - 1, 1 do

  for x = 0, w - 1, 1 do

   -- Fractionalize image dimensions

   ox = x / w;

   oy = y / h;

   -- Ball

   Xr = ox-0.5; Yr = oy-0.5;

   W = (1 - 2*math.sqrt(Xr*Xr + Yr*Yr));

   -- 'FishEye' distortion / Fake 3D

   F = (math.cos((ox-0.5)*math.pi)*math.cos((oy-0.5)*math.pi))*0.65;

   ox = ox - (ox-0.5)*F;

   oy = oy - (oy-0.5)*F;

   -- Checkers

   V = ((math.floor(0.25+ox*10)+math.floor(1+oy*10)) % 2) * 255 * W;

   -- Specularities

   SPEC1 = math.max(0,(1-5*math.sqrt((ox-0.45)*(ox-0.45)+(oy-0.45)*(oy-0.45)))*112);

   SPEC2 = math.max(0,(1-15*math.sqrt((ox-0.49)*(ox-0.49)+(oy-0.48)*(oy-0.48)))*255);

   r = W * 255 + SPEC1 + SPEC2

   g = V + SPEC1 + SPEC2

   b = V + SPEC1 + SPEC2

   putbrushpixel(x, y, matchcolor(r,g,b));

  end

end