polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx

Updated fg_geodesy comments to reflect that routines expect and produce meters.
1998-07-08 14:40:07 +00:00
parent 4205c0a38d
commit dbcecbd3b8
7 changed files with 128 additions and 66 deletions
--- a/Math/vector.cxx
+++ b/Math/vector.cxx
@@ -0,0 +1,130 @@
+/**************************************************************************
+ * vector.c -- additional vector routines
+ *
+ * Written by Curtis Olson, started December 1997.
+ *
+ * Copyright (C) 1997  Curtis L. Olson  - curt@infoplane.com
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id$
+ * (Log is kept at end of this file)
+ **************************************************************************/
+
+
+#include <math.h>
+#include <stdio.h>
+
+#include <Include/fg_types.h>
+
+#include "vector.hxx"
+
+#include "mat3.h"
+
+
+/* Map a vector onto the plane specified by normal */
+void map_vec_onto_cur_surface_plane(MAT3vec normal, MAT3vec v0, MAT3vec vec,
+				    MAT3vec result)
+{
+    MAT3vec u1, v, tmp;
+
+    /* calculate a vector "u1" representing the shortest distance from
+     * the plane specified by normal and v0 to a point specified by
+     * "vec".  "u1" represents both the direction and magnitude of
+     * this desired distance. */
+
+    /* u1 = ( (normal <dot> vec) / (normal <dot> normal) ) * normal */
+
+    MAT3_SCALE_VEC( u1,
+		    normal,
+		    ( MAT3_DOT_PRODUCT(normal, vec) /
+		      MAT3_DOT_PRODUCT(normal, normal)
+		      )
+		    );
+
+    /*
+    printf("  vec = %.2f, %.2f, %.2f\n", vec[0], vec[1], vec[2]);
+    printf("  v0 = %.2f, %.2f, %.2f\n", v0[0], v0[1], v0[2]);
+    printf("  u1 = %.2f, %.2f, %.2f\n", u1[0], u1[1], u1[2]);
+    */
+
+    /* calculate the vector "v" which is the vector "vec" mapped onto
+       the plane specified by "normal" and "v0". */
+
+    /* v = v0 + vec - u1 */
+
+    MAT3_ADD_VEC(tmp, v0, vec);
+    MAT3_SUB_VEC(v, tmp, u1);
+    /* printf("  v = %.2f, %.2f, %.2f\n", v[0], v[1], v[2]); */
+
+    /* Calculate the vector "result" which is "v" - "v0" which is a
+     * directional vector pointing from v0 towards v */
+
+    /* result = v - v0 */
+
+    MAT3_SUB_VEC(result, v, v0);
+    /* printf("  result = %.2f, %.2f, %.2f\n", 
+       result[0], result[1], result[2]); */
+}
+
+
+// Given a point p, and a line through p0 with direction vector d,
+// find the shortest distance from the point to the line
+double fgPointLine(MAT3vec p, MAT3vec p0, MAT3vec d) {
+    MAT3vec u, u1, v;
+    double ud, dd, tmp, dist;
+    
+    // u = p - p0
+    MAT3_SUB_VEC(u, p, p0);
+
+    // calculate the projection, u1, of u along d.
+    // u1 = ( dot_prod(u, d) / dot_prod(d, d) ) * d;
+    ud = MAT3_DOT_PRODUCT(u, d);
+    dd = MAT3_DOT_PRODUCT(d, d);
+    tmp = ud / dd;
+
+    MAT3_SCALE_VEC(u1, d, tmp);;
+
+    // v = u - u1 = vector from closest point on line, p1, to the
+    // original point, p.
+    MAT3_SUB_VEC(v, u, u1);
+
+    dist = sqrt(MAT3_DOT_PRODUCT(v, v));
+
+    return( dist );
+}
+
+
+/* $Log$
+/* Revision 1.1  1998/07/08 14:40:10  curt
+/* polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx
+/* Updated fg_geodesy comments to reflect that routines expect and produce
+/*   meters.
+/*
+ * Revision 1.3  1998/05/07 23:04:28  curt
+ * Added a blank formating line!
+ *
+ * Revision 1.2  1998/01/19 19:27:13  curt
+ * Merged in make system changes from Bob Kuehne <rpk@sgi.com>
+ * This should simplify things tremendously.
+ *
+ * Revision 1.1  1997/12/22 04:13:17  curt
+ * Initial revision.
+ * */
+
+
+
+
+