dust3d/dust3d/base/vector2.h

277 lines
8.9 KiB
C++

/*
* Copyright (c) 2016-2021 Jeremy HU <jeremy-at-dust3d dot org>. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
* Vector2::isInPolygon contains code translated from https://wrf.ecse.rpi.edu/Research/Short_Notes/pnpoly.html
* Copyright (c) 1970-2003, Wm. Randolph Franklin
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimers.
* Redistributions in binary form must reproduce the above copyright notice in the documentation and/or other materials provided with the distribution.
* The name of W. Randolph Franklin may not be used to endorse or promote products derived from this Software without specific prior written permission.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#ifndef DUST3D_BASE_VECTOR2_H_
#define DUST3D_BASE_VECTOR2_H_
#include <vector>
#include <string>
#include <iostream>
#include <dust3d/base/math.h>
namespace dust3d
{
class Vector2;
inline Vector2 operator*(double number, const Vector2 &v);
inline Vector2 operator*(const Vector2 &v, double number);
inline Vector2 operator+(const Vector2 &a, const Vector2 &b);
inline Vector2 operator-(const Vector2 &a, const Vector2 &b);
class Vector2
{
public:
inline Vector2() :
m_data {0.0, 0.0}
{
}
inline Vector2(double x, double y) :
m_data {x, y}
{
}
inline double &operator[](size_t index)
{
return m_data[index];
}
inline const double &operator[](size_t index) const
{
return m_data[index];
}
inline const double &x() const
{
return m_data[0];
}
inline const double &y() const
{
return m_data[1];
}
inline void setX(double x)
{
m_data[0] = x;
}
inline void setY(double y)
{
m_data[1] = y;
}
inline const double *data() const
{
return &m_data[0];
}
inline void setData(double x, double y)
{
m_data[0] = x;
m_data[1] = y;
}
inline double lengthSquared() const
{
return x() * x() + y() * y();
}
inline double length() const
{
double length2 = x() * x() + y() * y();
return std::sqrt(length2);
}
inline Vector2 normalized() const
{
double length2 = x() * x() + y() * y();
double length = std::sqrt(length2);
if (Math::isZero(length))
return Vector2();
return Vector2(x() / length, y() / length);
}
inline void normalize()
{
double length2 = x() * x() + y() * y();
double length = std::sqrt(length2);
if (Math::isZero(length))
return;
m_data[0] = x() / length;
m_data[1] = y() / length;
}
inline bool isOnLeft(const Vector2 &a, const Vector2 &b) const
{
return ((b.x() - a.x()) * (y() - a.y()) - (b.y() - a.y()) * (x() - a.x())) > 0;
}
inline static double dotProduct(const Vector2 &a, const Vector2 &b)
{
return a.x() * b.x() + a.y() * b.y();
}
inline static Vector2 barycentricCoordinates(const Vector2 &a, const Vector2 &b, const Vector2 &c, const Vector2 &point)
{
auto v0 = c - a;
auto v1 = b - a;
auto v2 = point - a;
auto dot00 = dotProduct(v0, v0);
auto dot01 = dotProduct(v0, v1);
auto dot02 = dotProduct(v0, v2);
auto dot11 = dotProduct(v1, v1);
auto dot12 = dotProduct(v1, v2);
auto invDenom = 1.0 / (dot00 * dot11 - dot01 * dot01);
auto alpha = (dot11 * dot02 - dot01 * dot12) * invDenom;
auto beta = (dot00 * dot12 - dot01 * dot02) * invDenom;
return Vector2(alpha, beta);
}
inline static bool isInTriangle(const Vector2 &a, const Vector2 &b, const Vector2 &c, const Vector2 &point)
{
auto alphaAndBeta = barycentricCoordinates(a, b, c, point);
if (alphaAndBeta[0] < 0)
return false;
if (alphaAndBeta[1] < 0)
return false;
if ((1.0 - (alphaAndBeta[0] + alphaAndBeta[1])) < 0)
return false;
return true;
}
inline bool isInPolygon(const std::vector<Vector2> &polygon) const
{
bool inside = false;
int i, j;
for (i = 0, j = (int)polygon.size() - 1; i < (int)polygon.size(); j = i++) {
if (((polygon[i].y() > y()) != (polygon[j].y() > y())) &&
(x() < (polygon[j].x() - polygon[i].x()) * (y() - polygon[i].y()) / (polygon[j].y() - polygon[i].y()) + polygon[i].x())) {
inside = !inside;
}
}
return inside;
}
inline bool isInPolygon(const std::vector<Vector2> &polygonVertices, const std::vector<size_t> &polygonIndices) const
{
bool inside = false;
int i, j;
for (i = 0, j = (int)polygonIndices.size() - 1; i < (int)polygonIndices.size(); j = i++) {
if (((polygonVertices[polygonIndices[i]].y() > y()) != (polygonVertices[polygonIndices[j]].y() > y())) &&
(x() < (polygonVertices[polygonIndices[j]].x() - polygonVertices[polygonIndices[i]].x()) * (y() - polygonVertices[polygonIndices[i]].y()) / (polygonVertices[polygonIndices[j]].y() - polygonVertices[polygonIndices[i]].y()) + polygonVertices[polygonIndices[i]].x())) {
inside = !inside;
}
}
return inside;
}
inline Vector2 &operator+=(const Vector2 &other)
{
m_data[0] += other.x();
m_data[1] += other.y();
return *this;
}
inline bool isZero() const
{
return Math::isZero(m_data[0]) &&
Math::isZero(m_data[1]);
}
private:
double m_data[2] = {0.0};
};
inline Vector2 operator*(double number, const Vector2 &v)
{
return Vector2(number * v.x(), number * v.y());
}
inline Vector2 operator*(const Vector2 &v, double number)
{
return Vector2(number * v.x(), number * v.y());
}
inline Vector2 operator+(const Vector2 &a, const Vector2 &b)
{
return Vector2(a.x() + b.x(), a.y() + b.y());
}
inline Vector2 operator-(const Vector2 &a, const Vector2 &b)
{
return Vector2(a.x() - b.x(), a.y() - b.y());
}
inline Vector2 operator/(const Vector2 &v, double number)
{
return Vector2(v.x() / number, v.y() / number);
}
inline std::string to_string(const Vector2 &v)
{
return std::to_string(v.x()) + "," + std::to_string(v.y());
}
inline std::ostream &operator<<(std::ostream &os, const Vector2 &v)
{
os << v.x() << ',' << v.y();
return os;
}
inline bool operator==(const Vector2 &a, const Vector2 &b)
{
return Math::isEqual(a.x(), b.x()) &&
Math::isEqual(a.y(), b.y());
}
inline bool operator!=(const Vector2 &a, const Vector2 &b)
{
return !Math::isEqual(a.x(), b.x()) ||
!Math::isEqual(a.y(), b.y());
}
}
#endif