73 lines
1.8 KiB
C++
73 lines
1.8 KiB
C++
/* ScummVM - Graphic Adventure Engine
|
|
*
|
|
* ScummVM 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 3 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, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* This code is based on the CRAB engine
|
|
*
|
|
* Copyright (c) Arvind Raja Yadav
|
|
*
|
|
* Licensed under MIT
|
|
*
|
|
*/
|
|
|
|
#ifndef CRAB_LINE_H
|
|
#define CRAB_LINE_H
|
|
|
|
#include "crab/vectors.h"
|
|
|
|
namespace Crab {
|
|
|
|
// Find if 2 lines intersect and store the point of intersection
|
|
template<typename T>
|
|
bool collideLine(const T &p0X, const T &p0Y, const T &p1X, const T &p1Y,
|
|
const T &p2X, const T &p2Y, const T &p3X, const T &p3Y,
|
|
T *x = nullptr, T *y = nullptr) {
|
|
Vector2D<T> s1, s2;
|
|
s1.x = p1X - p0X;
|
|
s1.y = p1Y - p0Y;
|
|
s2.x = p3X - p2X;
|
|
s2.y = p3Y - p2Y;
|
|
|
|
float d = (-s2.x * s1.y + s1.x * s2.y);
|
|
|
|
if (d != 0) {
|
|
float s, t;
|
|
s = (-s1.y * (p0X - p2X) + s1.x * (p0Y - p2Y)) / d;
|
|
t = (s2.x * (p0Y - p2Y) - s2.y * (p0X - p2X)) / d;
|
|
|
|
if (s >= 0 && s <= 1 && t >= 0 && t <= 1) {
|
|
// Collision detected
|
|
if (x != nullptr)
|
|
*x = p0X + (t * s1.x);
|
|
if (y != nullptr)
|
|
*y = p0Y + (t * s1.y);
|
|
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false; // No collision
|
|
}
|
|
|
|
} // End of namespace Crab
|
|
|
|
#endif // CRAB_LINE_H
|