/*
* Copyright (c) 2012 matheusdev
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package org.matheusdev.noises.noise2;
import org.matheusdev.interpolation.FloatInterpolation;
import org.matheusdev.util.FastRand;
import org.matheusdev.util.vecs.Vec2i;
/**
* @author matheusdev
*
*/
public class SimplexNoiseLayerLazy2 implements Noise2 {
protected final long seed;
protected final int density;
protected final FastRand rand;
protected final FloatInterpolation interpolator;
public SimplexNoiseLayerLazy2(final int density, final FloatInterpolation interpolator) {
this(new FastRand().randLong(), density, interpolator);
}
public SimplexNoiseLayerLazy2(final long seed, final int density, final FloatInterpolation interpolator) {
this.density = density;
this.seed = seed;
this.rand = new FastRand();
this.interpolator = interpolator;
}
public float get(float x, float y) {
// Bugfix thanks to "marcuiulian13"
// TODO: Optimize flooring algorithm...
final int cellX0 = (int) Math.floor(x / density);
final int cellY0 = (int) Math.floor(y / density);
final int cellX1 = (int) Math.floor(x / density) + 1;
final int cellY1 = (int) Math.floor(y / density) + 1;
final float value00 = getRand(cellX0, cellY0).randBool() ? -1f : 1f;
final float value10 = getRand(cellX1, cellY0).randBool() ? -1f : 1f;
final float value11 = getRand(cellX1, cellY1).randBool() ? -1f : 1f;
final float value01 = getRand(cellX0, cellY1).randBool() ? -1f : 1f;
final float relativeX = x - (cellX0 * density);
final float relativeY = y - (cellY0 * density);
final float timeX = relativeX / density;
final float timeY = relativeY / density;
final float interpolationHoriz0 =
interpolator.interpolate(
timeX, value00, 0, value10, 1);
final float interpolationHoriz1 =
interpolator.interpolate(
timeX, value01, 0, value11, 1);
final float interpolationVert =
interpolator.interpolate(
timeY, interpolationHoriz0, 0f, interpolationHoriz1, 1f);
return interpolationVert;
}
private static long hashWang(long key) {
key = (~key) + (key << 21); // key = (key << 21) - key - 1;
key = key ^ (key >>> 24);
key = (key + (key << 3)) + (key << 8); // key * 265
key = key ^ (key >>> 14);
key = (key + (key << 2)) + (key << 4); // key * 21
key = key ^ (key >>> 28);
key = key + (key << 31);
return key;
}
private FastRand getRand(int x, int y) {
rand.setSeed(hashWang((x << 17) ^ y) + seed);
return rand;
}
}