/* Copyright (C) 2011 Garrett Fleenor
This library 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 3.0 of the License, or (at
your option) any later version.
This library 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 (COPYING.txt) for more details.
You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation,
Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
This is a port of libnoise ( http://libnoise.sourceforge.net/index.html ). Original implementation by Jason Bevins
*/
package net.royawesome.jlibnoise.model;
import net.royawesome.jlibnoise.Utils;
import net.royawesome.jlibnoise.exception.NoModuleException;
import net.royawesome.jlibnoise.module.Module;
/**
* Model that defines the surface of a sphere.
*
* @image html modelsphere.png
*
* This model returns an output value from a noise module given the
* coordinates of an input value located on the surface of a sphere.
*
* To generate an output value, pass the (latitude, longitude)
* coordinates of an input value to the GetValue() method.
*
* This model is useful for creating: - seamless textures that can be
* mapped onto a sphere - terrain height maps for entire planets
*
* This sphere has a radius of 1.0 unit and its center is located at the
* origin.
*/
public class Sphere {
Module module;
/**
* Constructor
*
* @param module The noise module that is used to generate the output
* values.
*/
public Sphere(Module module) {
if (module == null)
throw new IllegalArgumentException("module cannot be null");
this.module = module;
}
/**
* Returns the noise module that is used to generate the output values.
*
* @returns A reference to the noise module.
* @pre A noise module was passed to the SetModule() method.
*/
public Module getModule() {
return module;
}
/**
* Sets the noise module that is used to generate the output values.
*
* @param module The noise module that is used to generate the output
* values.
*
* This noise module must exist for the lifetime of this object,
* until you pass a new noise module to this method.
*/
public void setModule(Module module) {
if (module == null)
throw new IllegalArgumentException("module cannot be null");
this.module = module;
}
/**
* Returns the output value from the noise module given the (latitude,
* longitude) coordinates of the specified input value located on the
* surface of the sphere.
*
* @param lat The latitude of the input value, in degrees.
* @param lon The longitude of the input value, in degrees.
* @return The output value from the noise module.
* @pre A noise module was passed to the SetModule() method.
*
* This output value is generated by the noise module passed to the
* SetModule() method.
*
* Use a negative latitude if the input value is located on the
* southern hemisphere.
*
* Use a negative longitude if the input value is located on the
* western hemisphere.
*/
public double getValue(double lat, double log) {
if (module == null)
throw new NoModuleException();
double[] vec = Utils.LatLonToXYZ(lat, log);
return module.GetValue(vec[0], vec[1], vec[2]);
}
}