| /* | |
| * Copyright (C) 1999-2010 Anthony Lomax <anthony@alomax.net, http://www.alomax.net> | |
| * | |
| * This program is free software: you can redistribute it and/or modify | |
| * it under the terms of the GNU Lesser Public License as published by | |
| * the Free Software Foundation, either version 3 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 Lesser Public License for more details. | |
| * You should have received a copy of the GNU Lesser Public License | |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. | |
| */ | |
| /* Vector mathematics functions | |
| Anthony Lomax | |
| Nov 1992 | |
| */ | |
| /*** function to calculate dot product of 3-D vectors (A o B) */ | |
| double dot_product_3d(a1, a2, a3, b1, b2, b3) | |
| double a1, a2, a3, b1, b2, b3; | |
| { | |
| return(a1 * b1 + a2 * b2 + a3 * b3); | |
| } | |
| /*** function to calculate cross product of 3-D vectors (A X B) */ | |
| int cross_product_3d(a1, a2, a3, b1, b2, b3, p1, p2, p3) | |
| double a1, a2, a3, b1, b2, b3; | |
| double *p1, *p2, *p3; | |
| { | |
| *p1 = a2 * b3 - a3 * b2; | |
| *p2 = a3 * b1 - a1 * b3; | |
| *p3 = a1 * b2 - a2 * b1; | |
| return(0); | |
| } | |
| /*** function to calculate magnitude of 3-D vectors ||A|| */ | |
| double magnitude_3d(a1, a2, a3) | |
| double a1, a2, a3; | |
| { | |
| return(sqrt(a1 * a1 + a2 * a2 + a3 * a3)); | |
| } | |