Sha256: 742e5a8d475637d0ebb1e3f0329644367e233275993fc0562aafd657deb075c8
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Size: 1.54 KB
Versions: 6
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Stored size: 1.54 KB
Contents
package org.sunflow.core.gi;
import org.sunflow.core.GIEngine;
import org.sunflow.core.Options;
import org.sunflow.core.Scene;
import org.sunflow.core.ShadingState;
import org.sunflow.image.Color;
import org.sunflow.math.Vector3;
/**
* This is a quick way to get a bit of ambient lighting into your scene with
* hardly any overhead. It's based on the formula found here:
*
* @link http://www.cs.utah.edu/~shirley/papers/rtrt/node7.html#SECTION00031100000000000000
*/
public class FakeGIEngine implements GIEngine {
private Vector3 up;
private Color sky;
private Color ground;
@Override
public Color getIrradiance(ShadingState state, Color diffuseReflectance) {
float cosTheta = Vector3.dot(up, state.getNormal());
float sin2 = (1 - cosTheta * cosTheta);
float sine = sin2 > 0 ? (float) Math.sqrt(sin2) * 0.5f : 0;
if (cosTheta > 0) {
return Color.blend(sky, ground, sine);
} else {
return Color.blend(ground, sky, sine);
}
}
@Override
public Color getGlobalRadiance(ShadingState state) {
return Color.BLACK;
}
@Override
public boolean init(Options options, Scene scene) {
up = options.getVector("gi.fake.up", new Vector3(0, 1, 0)).normalize();
sky = options.getColor("gi.fake.sky", Color.WHITE).copy();
ground = options.getColor("gi.fake.ground", Color.BLACK).copy();
sky.mul((float) Math.PI);
ground.mul((float) Math.PI);
return true;
}
}
Version data entries
6 entries across 6 versions & 1 rubygems