ZTwisterFunc.java

/*
  JWildfire - an image and animation processor written in Java 
  Copyright (C) 1995-2011 Andreas Maschke

  This is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser 
  General Public License as published by the Free Software Foundation; either version 2.1 of the 
  License, or (at your option) any later version.
 
  This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without 
  even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License along with this software; 
  if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jwildfire.create.tina.variation;

import static org.jwildfire.base.mathlib.MathLib.cos;
import static org.jwildfire.base.mathlib.MathLib.pow;
import static org.jwildfire.base.mathlib.MathLib.sin;

import org.jwildfire.create.tina.base.XForm;
import org.jwildfire.create.tina.base.XYZPoint;

public class ZTwisterFunc extends VariationFunc {
  private static final long serialVersionUID = 1L;

  private static final String PARAM_TWIST = "twist";
  private static final String PARAM_BASE = "base";
  private static final String[] paramNames = { PARAM_TWIST, PARAM_BASE };

  private double twist = 4.2;
  private double base = Math.E;

  @Override
  public void transform(FlameTransformationContext pContext, XForm pXForm, XYZPoint pAffineTP, XYZPoint pVarTP, double pAmount) {
    // ztwister by dark-beam, http://jwildfire.org/forum/viewtopic.php?f=23&t=1500&p=2891#p2891
    double ez = twist * pVarTP.z;
    if (base != 1.0) {
      ez = pow(base, ez) - 1;
    }
    double sinz = sin(ez);
    double cosz = cos(ez);
    double nx = pAffineTP.x * cosz - pAffineTP.y * sinz;
    double ny = pAffineTP.x * sinz + pAffineTP.y * cosz;

    pVarTP.x += pAmount * nx;
    pVarTP.y += pAmount * ny;
    if (pContext.isPreserveZCoordinate()) {
  pVarTP.z += pAmount * pAffineTP.z;
}
  }

  @Override
  public String[] getParameterNames() {
    return paramNames;
  }

  @Override
  public Object[] getParameterValues() {
    return new Object[] { twist, base };
  }

  @Override
  public void setParameter(String pName, double pValue) {
    if (PARAM_TWIST.equalsIgnoreCase(pName))
      twist = pValue;
    else if (PARAM_BASE.equalsIgnoreCase(pName))
      base = pValue;
    else
      throw new IllegalArgumentException(pName);
  }

  @Override
  public String getName() {
    return "ztwister";
  }

}