/*******************************************************************************
* Breakout Cave Survey Visualizer
*
* Copyright (C) 2014 James Edwards
*
* jedwards8 at fastmail dot fm
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option) any later
* version.
*
* This program 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 program; if not, write to the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*******************************************************************************/
package org.andork.math3d;
public class RayIntersectsBoxTester {
public static boolean rayIntersects(float[] rayOrigin, float[] rayDirection, float[] rect) {
for (int d = 0; d < 3; d++) {
if (rayOrigin[d] <= rect[d] && rayDirection[d] < 0
|| rayOrigin[d] >= rect[d + 3] && rayDirection[d] > 0) {
return false;
}
}
for (int d0 = 0; d0 < 3; d0++) {
if (rayDirection[d0] == 0) {
if (rayOrigin[d0] < rect[d0] || rayOrigin[d0] > rect[d0 + 3]) {
return false;
}
continue;
}
float l0;
if (rayOrigin[d0] <= rect[d0]) {
l0 = rect[d0] - rayOrigin[d0];
} else if (rayOrigin[d0] >= rect[d0 + 3]) {
l0 = rect[d0 + 3] - rayOrigin[d0];
} else {
continue;
}
for (int i = 1; i < 3; i++) {
int d1 = (d0 + i) % 3;
float l1 = rayDirection[d1] * l0 / rayDirection[d0];
if (rayOrigin[d1] <= rect[d1 + 3] && rayOrigin[d1] + l1 > rect[d1 + 3] ||
rayOrigin[d1] >= rect[d1] && rayOrigin[d1] + l1 < rect[d1]) {
return false;
}
}
}
return true;
}
}