line: add trivial line type

This commit is contained in:
Danny Robson 2015-02-19 13:28:56 +11:00
parent ae6745a66a
commit ebfa147cd2
4 changed files with 122 additions and 0 deletions

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@ -77,6 +77,8 @@ UTIL_FILES = \
json/tree.hpp \
lerp.cpp \
lerp.hpp \
line.cpp \
line.hpp \
log.cpp \
log.hpp \
log.ipp \
@ -239,6 +241,7 @@ TEST_BIN = \
test/hton \
test/ip \
test/json_types \
test/line \
test/maths \
test/maths_matrix \
test/matrix \

60
line.cpp Normal file
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@ -0,0 +1,60 @@
/*
* This file is part of libgim.
*
* libgim 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 3 of the License, or (at your option) any later
* version.
*
* libgim 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 libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#include "line.hpp"
#include "debug.hpp"
//-----------------------------------------------------------------------------
template <size_t S, typename T>
util::line<S,T>::line (util::point<S,T> _p,
util::vector<S,T> _d):
p (_p),
d (_d)
{
CHECK_EQ (d.magnitude2 (), 1);
}
///----------------------------------------------------------------------------
/// returns the distance alone the line in a line-plane intersection
///
/// returns inf if parallel
/// returns 0 if colinear
template <size_t S, typename T>
T
util::line<S,T>::intersect (plane<S,T> rhs) const
{
return dot (rhs.p - p, rhs.n) / dot (d, rhs.n);
}
//-----------------------------------------------------------------------------
template <size_t S, typename T>
util::point<S,T>
util::line<S,T>::at (T t) const
{
return p + d * t;
}
//-----------------------------------------------------------------------------
template struct util::line<2,float>;
template struct util::line<3,float>;

46
line.hpp Normal file
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@ -0,0 +1,46 @@
/*
* This file is part of libgim.
*
* libgim 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 3 of the License, or (at your option) any later
* version.
*
* libgim 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 libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#ifndef __UTIL_LINE_HPP
#define __UTIL_LINE_HPP
#include "point.hpp"
#include "vector.hpp"
#include "plane.hpp"
namespace util {
template <size_t S, typename T>
struct line {
line (util::point<S,T> place,
util::vector<S,T> direction);
T intersect (plane<S,T>) const;
util::point<S,T> at (T) const;
util::point<S,T> p;
util::vector<S,T> d;
};
typedef line<2,float> line2f;
typedef line<3,float> line3f;
}
#endif

13
test/line.cpp Normal file
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@ -0,0 +1,13 @@
#include "line.hpp"
#include "plane.hpp"
#include "debug.hpp"
int
main (void)
{
// trivial case: origin line facing z, plane at unit z facing -z.
util::line3f l ({0,0,0}, {0,0, 1});
util::plane3f p ({0,0,1}, {0,0,-1});
CHECK_EQ (l.intersect (p), 1);
}