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fgPointLine() rewritten into fgPointLineSquared() ... this ultimately saves

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us from doing a sqrt().
This commit is contained in:
curt 1998-07-24 21:34:38 +00:00
parent fca7a8fa47
commit 6dd8a1525c
2 changed files with 22 additions and 16 deletions
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22
Math/vector.cxx
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@ -81,10 +81,10 @@ void map_vec_onto_cur_surface_plane(MAT3vec normal, MAT3vec v0, MAT3vec vec,
// 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) {
// find the shortest distance (squared) from the point to the line
double fgPointLineSquared(MAT3vec p, MAT3vec p0, MAT3vec d) {
MAT3vec u, u1, v;
double ud, dd, tmp, dist;
double ud, dd, tmp;
// u = p - p0
MAT3_SUB_VEC(u, p, p0);
@ -101,18 +101,20 @@ double fgPointLine(MAT3vec p, MAT3vec p0, MAT3vec d) {
// original point, p.
MAT3_SUB_VEC(v, u, u1);
dist = sqrt(MAT3_DOT_PRODUCT(v, v));
return( dist );
return ( MAT3_DOT_PRODUCT(v, v) );
}
/* $Log$
/* 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 1.2 1998/07/24 21:34:38 curt
/* fgPointLine() rewritten into fgPointLineSquared() ... this ultimately saves
/* us from doing a sqrt().
/*
* 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!
*

16
Math/vector.hxx
View File

@ -41,19 +41,23 @@ void map_vec_onto_cur_surface_plane(MAT3vec normal, MAT3vec v0, MAT3vec vec,
MAT3vec result);
// 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);
// find the shortest distance (squared) from the point to the line
double fgPointLineSquared(MAT3vec p, MAT3vec p0, MAT3vec d);
#endif /* _VECTOR_HXX */
/* $Log$
/* 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 1.2 1998/07/24 21:34:38 curt
/* fgPointLine() rewritten into fgPointLineSquared() ... this ultimately saves
/* us from doing a sqrt().
/*
* 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 1.4 1998/04/21 17:03:51 curt
* Prepairing for C++ integration.
*