scummvm/math/line3d.cpp
2021-04-05 23:08:48 +02:00

96 lines
2.7 KiB
C++

/* ResidualVM - A 3D game interpreter
*
* ResidualVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include "math/line3d.h"
namespace Math {
Line3d::Line3d() {
}
Line3d::Line3d(const Vector3d &b, const Vector3d &e) :
_begin(b), _end(e) {
}
Line3d::Line3d(const Line3d &other) {
*this = other;
}
Math::Vector3d Line3d::begin() const {
return _begin;
}
Math::Vector3d Line3d::end() const {
return _end;
}
Math::Vector3d Line3d::middle() const {
return (_begin + _end) / 2.f;
}
bool Line3d::intersectLine2d(const Line3d &other, Math::Vector3d *pos, bool useXZ) {
float denom, nume_a, nume_b;
if (useXZ) {
denom = ((other._end.z() - other._begin.z()) * (_end.x() - _begin.x())) -
((other._end.x() - other._begin.x()) * (_end.z() - _begin.z()));
nume_a = ((other._end.x() - other._begin.x()) * (_begin.z() - other._begin.z())) -
((other._end.z() - other._begin.z()) * (_begin.x() - other._begin.x()));
nume_b = ((_end.x() - _begin.x()) * (_begin.z() - other._begin.z())) -
((_end.z() - _begin.z()) * (_begin.x() - other._begin.x()));
} else {
denom = ((other._end.y() - other._begin.y()) * (_end.x() - _begin.x())) -
((other._end.x() - other._begin.x()) * (_end.y() - _begin.y()));
nume_a = ((other._end.x() - other._begin.x()) * (_begin.y() - other._begin.y())) -
((other._end.y() - other._begin.y()) * (_begin.x() - other._begin.x()));
nume_b = ((_end.x() - _begin.x()) * (_begin.y() - other._begin.y())) -
((_end.y() - _begin.y()) * (_begin.x() - other._begin.x()));
}
if (denom == 0.0f) {
return false;
}
float ua = nume_a / denom;
float ub = nume_b / denom;
if (ua < 0 || ua > 1 || ub < 0 || ub > 1)
return false;
// Get the intersection point.
if (pos)
*pos = _begin + ua * (_end - _begin);
return true;
}
Line3d& Line3d::operator=(const Line3d &other) {
_begin = other._begin;
_end = other._end;
return *this;
}
}