geom/line: add basic line class

This commit is contained in:
Danny Robson 2018-04-20 15:04:54 +10:00
parent e7b12e7792
commit 56a73275c1
4 changed files with 95 additions and 0 deletions

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@ -233,6 +233,8 @@ list (
geom/frustum.hpp geom/frustum.hpp
geom/iostream.cpp geom/iostream.cpp
geom/iostream.hpp geom/iostream.hpp
geom/line.hpp
geom/line.cpp
geom/ops.hpp geom/ops.hpp
geom/plane.cpp geom/plane.cpp
geom/plane.hpp geom/plane.hpp
@ -496,6 +498,8 @@ if (TESTS)
geom/aabb geom/aabb
geom/ellipse geom/ellipse
geom/frustum geom/frustum
geom/line
geom/plane
geom/ray geom/ray
geom/sphere geom/sphere
hash/checksum hash/checksum

0
geom/line.cpp Normal file
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63
geom/line.hpp Normal file
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@ -0,0 +1,63 @@
/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2018 Danny Robson <danny@nerdcruft.net>
*/
#pragma once
#include "../point.hpp"
#include "../vector.hpp"
namespace util::geom {
// an line of infinite extent that passes though 'base'.
//
// direction should be normalised
template <size_t S, typename T>
struct line {
line () = default;
line (util::point<S,T> a, util::point<S,T> b):
line (a, normalised (b - a))
{ ; }
line (util::point<S,T> _base, util::vector<S,T> _direction):
base (_base),
direction (_direction)
{
CHECK (is_normalised (direction));
}
util::point<S,T> base;
util::vector<S,T> direction;
};
using line2f = line<2,float>;
using line3f = line<3,float>;
template <size_t S, typename T>
T
distance2 (line<S,T> l, point<S,T> p)
{
const auto t = dot (p - l.base, l.direction);
return distance2 (p, l.base + l.direction * t);
}
template <size_t S, typename T>
T
distance (line<S,T> l, point<S,T> p)
{
return std::sqrt (distance2 (l, p));
}
};

28
test/geom/line.cpp Normal file
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#include "tap.hpp"
#include "geom/line.hpp"
int
main (int, char**)
{
util::TAP::logger tap;
static struct {
util::point3f origin;
util::vector3f direction;
util::point3f q;
float distance;
const char *message;
} TESTS[] = {
{ { 0, 0, 0 }, { 1, 0, 0}, { 0, 0, 0 }, 0, "origin line, origin point" } ,
{ { 0, 1, 0 }, { 1, 0, 0}, { 0, 0, 0 }, 1, "+x line, unit distance" },
};
for (auto const& t: TESTS) {
util::geom::line3f l { t.origin, t.direction };
auto d = distance2 (l, t.q);
tap.expect_eq (d, t.distance, "%!", t.message);
}
return tap.status ();
}