3 * Additional vector routines.
6 // Written by Curtis Olson, started December 1997.
8 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
10 // This library is free software; you can redistribute it and/or
11 // modify it under the terms of the GNU Library General Public
12 // License as published by the Free Software Foundation; either
13 // version 2 of the License, or (at your option) any later version.
15 // This library is distributed in the hope that it will be useful,
16 // but WITHOUT ANY WARRANTY; without even the implied warranty of
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 // Library General Public License for more details.
20 // You should have received a copy of the GNU Library General Public
21 // License along with this library; if not, write to the
22 // Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 // Boston, MA 02111-1307, USA.
33 # error This library requires C++
40 #include <simgear/compiler.h>
46 * Map a vector onto a plane.
47 * @param normal (in) normal vector for the plane
48 * @param v0 (in) a point on the plane
49 * @param vec (in) the vector to map onto the plane
50 * @param result (out) the result vector
52 inline void sgmap_vec_onto_cur_surface_plane( sgVec3 normal,
59 // calculate a vector "u1" representing the shortest distance from
60 // the plane specified by normal and v0 to a point specified by
61 // "vec". "u1" represents both the direction and magnitude of
62 // this desired distance.
64 // u1 = ( (normal <dot> vec) / (normal <dot> normal) ) * normal
68 ( sgScalarProductVec3(normal, vec) /
69 sgScalarProductVec3(normal, normal)
73 // printf(" vec = %.2f, %.2f, %.2f\n", vec[0], vec[1], vec[2]);
74 // printf(" v0 = %.2f, %.2f, %.2f\n", v0[0], v0[1], v0[2]);
75 // printf(" u1 = %.2f, %.2f, %.2f\n", u1[0], u1[1], u1[2]);
77 // calculate the vector "v" which is the vector "vec" mapped onto
78 // the plane specified by "normal" and "v0".
82 sgAddVec3(tmp, v0, vec);
83 sgSubVec3(v, tmp, u1);
84 // printf(" v = %.2f, %.2f, %.2f\n", v[0], v[1], v[2]);
86 // Calculate the vector "result" which is "v" - "v0" which is a
87 // directional vector pointing from v0 towards v
91 sgSubVec3(result, v, v0);
92 // printf(" result = %.2f, %.2f, %.2f\n",
93 // result[0], result[1], result[2]);
98 * Copy and negate a vector.
99 * @param dst (out) result vector
100 * @param src (in) input vector
102 inline void sgCopyNegateVec4( sgVec4 dst, sgVec4 src )
104 dst [ 0 ] = -src [ 0 ] ;
105 dst [ 1 ] = -src [ 1 ] ;
106 dst [ 2 ] = -src [ 2 ] ;
107 dst [ 3 ] = -src [ 3 ] ;
111 * Given a point p, and a line through p0 with direction vector d,
112 * find the closest point (p1) on the line (float version).
113 * @param p1 (out) closest point to p on the line
114 * @param p (in) original point
115 * @param p0 (in) point on the line
116 * @param d (in) vector defining line direction
118 void sgClosestPointToLine( sgVec3 p1, const sgVec3 p, const sgVec3 p0,
122 * Given a point p, and a line through p0 with direction vector d,
123 * find the closest point (p1) on the line (double version).
124 * @param p1 (out) closest point to p on the line
125 * @param p (in) original point
126 * @param p0 (in) point on the line
127 * @param d (in) vector defining line direction
129 void sgdClosestPointToLine( sgdVec3 p1, const sgdVec3 p, const sgdVec3 p0,
133 * Given a point p, and a line through p0 with direction vector d,
134 * find the shortest distance (squared) from the point to the line (float
136 * @param p (in) original point
137 * @param p0 (in) point on the line
138 * @param d (in) vector defining line direction
139 * @return shortest distance (squared) from p to line
141 double sgClosestPointToLineDistSquared( const sgVec3 p, const sgVec3 p0,
145 * Given a point p, and a line through p0 with direction vector d,
146 * find the shortest distance (squared) from the point to the line (double
148 * @param p (in) original point
149 * @param p0 (in) point on the line
150 * @param d (in) vector defining line direction
151 * @return shortest distance (squared) from p to line
153 double sgdClosestPointToLineDistSquared( const sgdVec3 p, const sgdVec3 p0,
159 * <li> sgMakeMatTrans4( sgMat4 sgTrans, sgVec3 trans )
160 * <li> sgPostMultMat4( sgMat4 src, sgTRANS );
162 * @param src starting sgMat4 matrix
163 * @param trans translation vector
165 void sgPostMultMat4ByTransMat4( sgMat4 src, const sgVec3 trans );
168 #endif // _VECTOR_HXX