principal_curvature.h

/*****************************************************************************
 * VCLib                                                                     *
 * Visual Computing Library                                                  *
 *                                                                           *
 * Copyright(C) 2021-2025                                                    *
 * Visual Computing Lab                                                      *
 * ISTI - Italian National Research Council                                  *
 *                                                                           *
 * All rights reserved.                                                      *
 *                                                                           *
 * 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_PRINCIPAL_CURVATURE_H
#define VCL_SPACE_CORE_PRINCIPAL_CURVATURE_H
 
#include "point.h"
 
namespace vcl {
 
template<typename Scalar>
class PrincipalCurvature
{
    Point3<Scalar> mDir1, mDir2;
    Scalar         mK1 = 0, mK2 = 0;
 
public:
    using ScalarType = Scalar;
 
    PrincipalCurvature() {}
 
    template<typename S>
    auto cast() const
    {
        if constexpr (std::is_same<Scalar, S>::value) {
            return *this;
        }
        else {
            PrincipalCurvature<S> tmp;
            tmp.maxDir()   = mDir1.template cast<S>();
            tmp.minDir()   = mDir2.template cast<S>();
            tmp.maxValue() = mK1;
            tmp.minValue() = mK2;
            return tmp;
        }
    }
 
    const Point3<Scalar>& maxDir() const { return mDir1; }
 
    Point3<Scalar>& maxDir() { return mDir1; }
 
    const Point3<Scalar>& minDir() const { return mDir2; }
 
    Point3<Scalar>& minDir() { return mDir2; }
 
    const Scalar& maxValue() const { return mK1; }
 
    Scalar& maxValue() { return mK1; }
 
    const Scalar& minValue() const { return mK2; }
 
    Scalar& minValue() { return mK2; }
 
    void serialize(std::ostream& os) const
    {
        mDir1.serialize(os);
        mDir1.serialize(os);
        vcl::serialize(os, mK1);
        vcl::serialize(os, mK2);
    }
 
    void deserialize(std::istream& is)
    {
        mDir1.deserialize(is);
        mDir2.deserialize(is);
        vcl::deserialize(is, mK1);
        vcl::deserialize(is, mK2);
    }
};
 
/* Specialization Aliases */
 
using PrincipalCurvaturef = PrincipalCurvature<float>;
 
using PrincipalCurvatured = PrincipalCurvature<double>;
 
/* Concepts */
 
template<typename T>
concept PrincipalCurvatureConcept =
    std::derived_from< // same type or derived type
        std::remove_cvref_t<T>,
        PrincipalCurvature<typename RemoveRef<T>::ScalarType>>;
 
} // namespace vcl
 
#endif // VCL_SPACE_CORE_PRINCIPAL_CURVATURE_H