jiBubbles.osl

#include <stdosl.h>

/*
 Simple bubbles shader for shaders.xyz beer foam challenge.
 
 Author: Julius Ihle
 Version: 1.0
*/


shader jiBubbles(
		color Position = 0,
                point offset = 0,
                int seed = 0,
                int maxNum = 10,
                float minSize = 0.5,
                float maxSize = 1.5,
                float gamma = 1,
                point spread = 1,
                output color outRGB = 0
)

{
    //point Pos = transform("world",P) - offset;
    color Pos = Position - offset;
  
    float bubbles = 0;
    
    for (float i = 0.0; i < maxNum ; ++i) {
        color randPos = cellnoise(i,seed) * spread - (spread/2);
        float randSize = minSize + cellnoise(i,seed+847) * (maxSize - minSize) / 1;
        bubbles = max( bubbles, 1-( pow( clamp(distance(randPos,Pos/randSize),0,1), gamma)) );         
        outRGB = bubbles;           
    }
    

}