segment.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
 *                                                                           *
 * Copyright(C) 2021-2025                                                    *
 * Visual Computing Lab                                                      *
 * ISTI - Italian National Research Council                                  *
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 * All rights reserved.                                                      *
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 * This program is free software; you can redistribute it and/or modify      *
 * it under the terms of the Mozilla Public License Version 2.0 as published *
 * by the Mozilla 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              *
 * Mozilla Public License Version 2.0                                        *
 * (https://www.mozilla.org/en-US/MPL/2.0/) for more details.                *
 ****************************************************************************/
 
#ifndef VCL_SPACE_CORE_SEGMENT_H
#define VCL_SPACE_CORE_SEGMENT_H
 
#include "point.h"
 
namespace vcl {
 
template<PointConcept PointT>
class Segment
{
    PointT mPoint0;
    PointT mPoint1;
 
public:
    using PointType = PointT;
 
    using ScalarType = PointT::ScalarType;
 
    static const uint DIM = PointT::DIM;
 
    Segment() {}
 
    Segment(const PointT& p0, const PointT& p1) : mPoint0(p0), mPoint1(p1) {}
 
    PointT& p0() { return mPoint0; }
 
    const PointT& p0() const { return mPoint0; }
 
    PointT& p1() { return mPoint1; }
 
    const PointT& p1() const { return mPoint1; }
 
    PointT midPoint() const { return (mPoint0 + mPoint1) / 2.0; }
 
    PointT direction() const { return mPoint1 - mPoint0; }
 
    PointT normalizedDirection() const
    {
        return (mPoint1 - mPoint0).normalize();
    }
 
    ScalarType length() const { (mPoint0 - mPoint1).norm(); }
 
    ScalarType squaredLength() const { (mPoint0 - mPoint1).squaredNorm(); }
 
    void flip() { std::swap(mPoint0, mPoint1); }
 
    bool operator==(const Segment<PointT>& s) const = default;
 
    bool operator!=(const Segment<PointT>& s) const = default;
 
    Segment<PointT> operator+(const Segment<PointT>& s) const
    {
        return Segment<PointT>(mPoint0 + s.mPoint0, mPoint1 + s.mPoint1);
    }
 
    Segment<PointT> operator-(const Segment<PointT>& s) const
    {
        return Segment<PointT>(mPoint0 - s.mPoint0, mPoint1 - s.mPoint1);
    }
 
    Segment<PointT> operator*(const ScalarType& s) const
    {
        return Segment<PointT>(mPoint0 * s, mPoint1 * s);
    }
 
    Segment<PointT> operator/(const ScalarType& s) const
    {
        return Segment<PointT>(mPoint0 / s, mPoint1 / s);
    }
 
    Segment<PointT>& operator+=(const Segment<PointT>& s) const
    {
        mPoint0 += s.mPoint0;
        mPoint1 += s.mPoint1;
        return *this;
    }
 
    Segment<PointT>& operator-=(const Segment<PointT>& s) const
    {
        mPoint0 -= s.mPoint0;
        mPoint1 -= s.mPoint1;
        return *this;
    }
 
    Segment<PointT>& operator*=(const ScalarType& s) const
    {
        mPoint0 *= s;
        mPoint1 *= s;
        return *this;
    }
 
    Segment<PointT>& operator/=(const ScalarType& s) const
    {
        mPoint0 /= s;
        mPoint1 /= s;
        return *this;
    }
};
 
/* Specialization Aliases */
 
template<typename S>
using Segment2 = Segment<Point2<S>>;
 
using Segment2i = Segment<Point2i>;
using Segment2f = Segment<Point2f>;
using Segment2d = Segment<Point2d>;
 
template<typename S>
using Segment3 = Segment<Point3<S>>;
 
using Segment3i = Segment<Point3i>;
using Segment3f = Segment<Point3f>;
using Segment3d = Segment<Point3d>;
 
/* Concepts */
 
template<typename T>
concept SegmentConcept = std::derived_from< // same type or derived type
    std::remove_cvref_t<T>,
    Segment<typename RemoveRef<T>::PointType>>;
 
template<typename T>
concept Segment2Concept = SegmentConcept<T> && RemoveRef<T>::DIM == 2;
 
template<typename T>
concept Segment3Concept = SegmentConcept<T> && RemoveRef<T>::DIM == 3;
 
} // namespace vcl
 
#endif // VCL_SPACE_CORE_SEGMENT_H