/*
* Open Source Physics software is free software as described near the bottom of this code file.
*
* For additional information and documentation on Open Source Physics please see:
* <http://www.opensourcephysics.org/>
*/
package org.opensourcephysics.display3d.simple3d.utils;
public class EllipsoidUtils extends ShapeUtils {
static public double[][][] createStandardEllipsoid(int nr, int nu, int nv, double angleu1, double angleu2, double anglev1, double anglev2, boolean top, boolean bottom, boolean left, boolean right) {
int totalN = nu*nv;
if(Math.abs(anglev2-anglev1)<180) {
if(bottom) {
totalN += nr*nu;
}
if(top) {
totalN += nr*nu;
}
}
if(Math.abs(angleu2-angleu1)<360) {
if(left) {
totalN += nr*nv;
}
if(right) {
totalN += nr*nv;
}
}
double[][][] data = new double[totalN][4][3];
// Compute sines and cosines
double[] cosu = new double[nu+1], sinu = new double[nu+1];
double[] cosv = new double[nv+1], sinv = new double[nv+1];
for(int u = 0; u<=nu; u++) {
double angle = ((nu-u)*angleu1+u*angleu2)*TO_RADIANS/nu;
cosu[u] = Math.cos(angle);
sinu[u] = Math.sin(angle);
}
for(int v = 0; v<=nv; v++) {
double angle = ((nv-v)*anglev1+v*anglev2)*TO_RADIANS/nv;
cosv[v] = Math.cos(angle)/2; // /2 because the size is the diameter
sinv[v] = Math.sin(angle)/2;
}
// Now compute the tiles
int tile = 0;
double[] center = new double[] {0, 0, 0};
{ // Tiles along the z axis
for(int v = 0; v<nv; v++) {
for(int u = 0; u<nu; u++, tile++) { // This ordering is important for the computations below (see ref)
for(int k = 0; k<3; k++) {
data[tile][0][k] = (cosu[u]*vectorx[k]+sinu[u]*vectory[k])*cosv[v]+sinv[v]*vectorz[k];
data[tile][1][k] = (cosu[u+1]*vectorx[k]+sinu[u+1]*vectory[k])*cosv[v]+sinv[v]*vectorz[k];
data[tile][2][k] = (cosu[u+1]*vectorx[k]+sinu[u+1]*vectory[k])*cosv[v+1]+sinv[v+1]*vectorz[k];
data[tile][3][k] = (cosu[u]*vectorx[k]+sinu[u]*vectory[k])*cosv[v+1]+sinv[v+1]*vectorz[k];
}
}
}
}
// Note : the computations below are valid only for the given vectorx, vectory and vectorz
if(Math.abs(anglev2-anglev1)<180) { // No need to close top or bottom is the sphere is 'round' enough
if(bottom) { // Tiles at bottom
center[2] = sinv[0];
// int ref=0; // not used
for(int u = 0; u<nu; u++) {
for(int i = 0; i<nr; i++, tile++) {
for(int k = 0; k<3; k++) {
data[tile][0][k] = ((nr-i)*center[k]+i*data[u][0][k])/nr; // should be ref+u
data[tile][1][k] = ((nr-i-1)*center[k]+(i+1)*data[u][0][k])/nr; // should be ref+u
data[tile][2][k] = ((nr-i-1)*center[k]+(i+1)*data[u][1][k])/nr; // should be ref+u
data[tile][3][k] = ((nr-i)*center[k]+i*data[u][1][k])/nr; // should be ref+u
}
}
}
}
if(top) { // Tiles at top
center[2] = sinv[nv];
int ref = nu*(nv-1);
for(int u = 0; u<nu; u++) {
for(int i = 0; i<nr; i++, tile++) {
for(int k = 0; k<3; k++) {
data[tile][0][k] = ((nr-i)*center[k]+i*data[ref+u][3][k])/nr;
data[tile][1][k] = ((nr-i-1)*center[k]+(i+1)*data[ref+u][3][k])/nr;
data[tile][2][k] = ((nr-i-1)*center[k]+(i+1)*data[ref+u][2][k])/nr;
data[tile][3][k] = ((nr-i)*center[k]+i*data[ref+u][2][k])/nr;
}
}
}
}
}
if(Math.abs(angleu2-angleu1)<360) { // No need to close left or right if the sphere is 'round' enough
// System.out.println ("Computing lateral tiles");
double[] nextCenter = new double[] {0, 0, 0};
if(right) { // Tiles at right
int ref = 0;
for(int j = 0; j<nv; j++, ref += nu) {
center[2] = sinv[j];
nextCenter[2] = sinv[j+1];
for(int i = 0; i<nr; i++, tile++) {
for(int k = 0; k<3; k++) {
data[tile][0][k] = ((nr-i)*center[k]+i*data[ref][0][k])/nr;
data[tile][1][k] = ((nr-i-1)*center[k]+(i+1)*data[ref][0][k])/nr;
data[tile][2][k] = ((nr-i-1)*nextCenter[k]+(i+1)*data[ref][3][k])/nr;
data[tile][3][k] = ((nr-i)*nextCenter[k]+i*data[ref][3][k])/nr;
}
}
}
}
if(left) { // Tiles at left
int ref = nu-1;
for(int j = 0; j<nv; j++, ref += nu) {
center[2] = sinv[j];
nextCenter[2] = sinv[j+1];
for(int i = 0; i<nr; i++, tile++) {
for(int k = 0; k<3; k++) {
data[tile][0][k] = ((nr-i)*center[k]+i*data[ref][1][k])/nr;
data[tile][1][k] = ((nr-i-1)*center[k]+(i+1)*data[ref][1][k])/nr;
data[tile][2][k] = ((nr-i-1)*nextCenter[k]+(i+1)*data[ref][2][k])/nr;
data[tile][3][k] = ((nr-i)*nextCenter[k]+i*data[ref][2][k])/nr;
}
}
}
}
}
return data;
}
}
/*
* Open Source Physics software is free software; you can redistribute
* it and/or modify it under the terms of the GNU General Public License (GPL) as
* published by the Free Software Foundation; either version 2 of the License,
* or(at your option) any later version.
* Code that uses any portion of the code in the org.opensourcephysics package
* or any subpackage (subdirectory) of this package must must also be be released
* under the GNU GPL license.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston MA 02111-1307 USA
* or view the license online at http://www.gnu.org/copyleft/gpl.html
*
* Copyright (c) 2007 The Open Source Physics project
* http://www.opensourcephysics.org
*/