Technodots hydra
From Adobe Labs
[edit]
Technodots source code
/*****************************************************************************
*
* Author: Joa Ebert
* http://blog.je2050.de
* Contact: j -at- je2050.de
*
*****************************************************************************/
kernel TechnoDots
< nameSpace: "popforge::ImageProcessing";
vendor: "Joa Ebert";
version: 1;
description: "Like a pixelate filter but using nice dots with spacing.";
>
{
parameter float spacing
<
minValue: 0.0;
maxValue: 16.0;
defaultValue: 2.0;
description: "Spacing between the dots.";
>;
parameter float radius
<
minValue: 1.0;
maxValue: 64.0;
defaultValue: 4.0;
description: "Radius of the dots.";
>;
parameter pixel4 fillColor
<
minValue: 0.0;
maxValue: 1.0;
defaultValue: 0.0;
description: "The fill or background color.";
>;
void evaluatePixel( in image4 source, out pixel4 result)
{
// xy0 = origin
// xy1 = translated
float2 xy0 = outCoord();
float2 xy1 = xy0;
// aabb of dot with spacing
float rs = radius * 2.0 + spacing;
// shift into square
xy1 -= mod( xy1, float2( rs, rs ) );
// put into the middle
xy1 += float2( radius );
// use constants
float a = length(xy0-xy1); // check if inside
float b = radius; // the radius
pixel4 c = fillColor;
pixel4 d = sampleNearest(source, xy1);
// no flash error with constant selection
result = ( a > b ) ? c : d;
/*
Smooth edges by Jan Van Coppenolle
pixel4 d = sampleNearest(source, xy1);
float o = smoothStep(b, b - 1.0, a);
result = c - c * o + d * o;
*/
}
}
