/*
* BioJava development code
*
* This code may be freely distributed and modified under the
* terms of the GNU Lesser General Public Licence. This should
* be distributed with the code. If you do not have a copy,
* see:
*
* http://www.gnu.org/copyleft/lesser.html
*
* Copyright for this code is held jointly by the individual
* authors. These should be listed in @author doc comments.
*
* For more information on the BioJava project and its aims,
* or to join the biojava-l mailing list, visit the home page
* at:
*
* http://www.biojava.org/
*
*/
package org.biojava.nbio.structure.symmetry.geometry;
import javax.vecmath.AxisAngle4d;
import javax.vecmath.Quat4d;
/**
* Represents an even coverage of quaternion space by 60 points. This grid is
* defined by the vertices of one half of a hexacosichoron (600-cell). It
* approximates all possible orientations to within 44.48 degrees.
* @author Peter
*/
// This would be better named HexacosichoronSampler, since it's sampling 4D space. -SB
public final class IcosahedralSampler {
private static Quat4d quat = new Quat4d();
// this class cannot be instantiated
private IcosahedralSampler() {
}
public static int getSphereCount() {
return orientations.length;
}
public static Quat4d getQuat4d(int index) {
Quat4d q = new Quat4d(orientations[index]); //ignores 5th element
return q;
}
public static void getAxisAngle(int index, AxisAngle4d axisAngle) {
quat.set(orientations[index]);
axisAngle.set(quat);
}
// # Orientation set c600v, number = 60, radius = 44.48 degrees
// # $Id: c600v.quat 6102 2006-02-21 19:45:40Z ckarney $
// # For more information, eee http://charles.karney.info/orientation/
// format quaternion
// The fifth column gives a weighting factor. Since the 600-cell is regular, all
// orientations cover an equal fraction of orientation space and have equal weight.
private static double[][] orientations = {
{1.000000000f, 0.000000000f, 0.000000000f, 0.000000000f, 1.000000f},
{0.000000000f, 1.000000000f, 0.000000000f, 0.000000000f, 1.000000f},
{0.000000000f, 0.000000000f, 1.000000000f, 0.000000000f, 1.000000f},
{0.000000000f, 0.000000000f, 0.000000000f, 1.000000000f, 1.000000f},
{0.000000000f, 0.500000000f, 0.309016994f, 0.809016994f, 1.000000f},
{0.000000000f, -0.500000000f, 0.309016994f, 0.809016994f, 1.000000f},
{0.000000000f, 0.500000000f, -0.309016994f, 0.809016994f, 1.000000f},
{-0.000000000f, -0.500000000f, -0.309016994f, 0.809016994f, 1.000000f},
{0.000000000f, 0.309016994f, 0.809016994f, 0.500000000f, 1.000000f},
{0.000000000f, -0.309016994f, 0.809016994f, 0.500000000f, 1.000000f},
{-0.000000000f, -0.309016994f, 0.809016994f, -0.500000000f, 1.000000f},
{0.000000000f, 0.309016994f, 0.809016994f, -0.500000000f, 1.000000f},
{0.000000000f, 0.809016994f, 0.500000000f, 0.309016994f, 1.000000f},
{-0.000000000f, 0.809016994f, -0.500000000f, -0.309016994f, 1.000000f},
{0.000000000f, 0.809016994f, -0.500000000f, 0.309016994f, 1.000000f},
{0.000000000f, 0.809016994f, 0.500000000f, -0.309016994f, 1.000000f},
{0.500000000f, 0.000000000f, 0.809016994f, 0.309016994f, 1.000000f},
{-0.500000000f, 0.000000000f, 0.809016994f, 0.309016994f, 1.000000f},
{-0.500000000f, -0.000000000f, 0.809016994f, -0.309016994f, 1.000000f},
{0.500000000f, 0.000000000f, 0.809016994f, -0.309016994f, 1.000000f},
{0.309016994f, 0.000000000f, 0.500000000f, 0.809016994f, 1.000000f},
{-0.309016994f, 0.000000000f, 0.500000000f, 0.809016994f, 1.000000f},
{0.309016994f, 0.000000000f, -0.500000000f, 0.809016994f, 1.000000f},
{-0.309016994f, -0.000000000f, -0.500000000f, 0.809016994f, 1.000000f},
{0.809016994f, 0.000000000f, 0.309016994f, 0.500000000f, 1.000000f},
{0.809016994f, -0.000000000f, -0.309016994f, -0.500000000f, 1.000000f},
{0.809016994f, 0.000000000f, -0.309016994f, 0.500000000f, 1.000000f},
{0.809016994f, 0.000000000f, 0.309016994f, -0.500000000f, 1.000000f},
{0.309016994f, 0.809016994f, 0.000000000f, 0.500000000f, 1.000000f},
{-0.309016994f, 0.809016994f, 0.000000000f, 0.500000000f, 1.000000f},
{-0.309016994f, 0.809016994f, -0.000000000f, -0.500000000f, 1.000000f},
{0.309016994f, 0.809016994f, 0.000000000f, -0.500000000f, 1.000000f},
{0.809016994f, 0.500000000f, 0.000000000f, 0.309016994f, 1.000000f},
{0.809016994f, -0.500000000f, -0.000000000f, -0.309016994f, 1.000000f},
{0.809016994f, -0.500000000f, 0.000000000f, 0.309016994f, 1.000000f},
{0.809016994f, 0.500000000f, 0.000000000f, -0.309016994f, 1.000000f},
{0.500000000f, 0.309016994f, 0.000000000f, 0.809016994f, 1.000000f},
{-0.500000000f, 0.309016994f, 0.000000000f, 0.809016994f, 1.000000f},
{0.500000000f, -0.309016994f, 0.000000000f, 0.809016994f, 1.000000f},
{-0.500000000f, -0.309016994f, -0.000000000f, 0.809016994f, 1.000000f},
{0.809016994f, 0.309016994f, 0.500000000f, 0.000000000f, 1.000000f},
{0.809016994f, -0.309016994f, -0.500000000f, -0.000000000f, 1.000000f},
{0.809016994f, -0.309016994f, 0.500000000f, 0.000000000f, 1.000000f},
{0.809016994f, 0.309016994f, -0.500000000f, 0.000000000f, 1.000000f},
{0.500000000f, 0.809016994f, 0.309016994f, 0.000000000f, 1.000000f},
{-0.500000000f, 0.809016994f, 0.309016994f, 0.000000000f, 1.000000f},
{-0.500000000f, 0.809016994f, -0.309016994f, -0.000000000f, 1.000000f},
{0.500000000f, 0.809016994f, -0.309016994f, 0.000000000f, 1.000000f},
{0.309016994f, 0.500000000f, 0.809016994f, 0.000000000f, 1.000000f},
{-0.309016994f, 0.500000000f, 0.809016994f, 0.000000000f, 1.000000f},
{0.309016994f, -0.500000000f, 0.809016994f, 0.000000000f, 1.000000f},
{-0.309016994f, -0.500000000f, 0.809016994f, -0.000000000f, 1.000000f},
{0.500000000f, 0.500000000f, 0.500000000f, 0.500000000f, 1.000000f},
{0.500000000f, -0.500000000f, -0.500000000f, -0.500000000f, 1.000000f},
{0.500000000f, -0.500000000f, 0.500000000f, 0.500000000f, 1.000000f},
{0.500000000f, 0.500000000f, -0.500000000f, 0.500000000f, 1.000000f},
{0.500000000f, 0.500000000f, 0.500000000f, -0.500000000f, 1.000000f},
{0.500000000f, 0.500000000f, -0.500000000f, -0.500000000f, 1.000000f},
{0.500000000f, -0.500000000f, 0.500000000f, -0.500000000f, 1.000000f},
{0.500000000f, -0.500000000f, -0.500000000f, 0.500000000f, 1.000000f},
};
}