quality.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_ALGORITHMS_MESH_UPDATE_QUALITY_H
#define VCL_ALGORITHMS_MESH_UPDATE_QUALITY_H
 
#include <vclib/algorithms/mesh/stat.h>
 
#include <vclib/algorithms/core.h>
#include <vclib/mesh.h>
 
namespace vcl {
 
template<uint ELEM_ID, MeshConcept MeshType, typename QualityType>
void setPerElementQuality(MeshType& mesh, QualityType quality)
{
    requirePerElementComponent<ELEM_ID, CompId::QUALITY>(mesh);
 
    std::ranges::fill(
        mesh.template elements<ELEM_ID>() | vcl::views::quality, quality);
}
 
template<uint ELEM_ID, MeshConcept MeshType, typename QualityType>
void clampPerElementQuality(MeshType& mesh, QualityType minQ, QualityType maxQ)
{
    requirePerElementComponent<ELEM_ID, CompId::QUALITY>(mesh);
 
    for (auto&& q : mesh.template elements<ELEM_ID>() | vcl::views::quality) {
        q = std::clamp(q, minQ, maxQ);
    }
}
 
template<uint ELEM_ID, MeshConcept MeshType, typename QualityType>
void normalizePerElementQuality(
    MeshType&   mesh,
    QualityType minQ = 0,
    QualityType maxQ = 1)
{
    requirePerElementComponent<ELEM_ID, CompId::QUALITY>(mesh);
 
    QualityType range   = maxQ - minQ;
    auto [eMinQ, eMaxQ] = elementQualityMinMax<ELEM_ID>(mesh);
 
    for (auto&& q : mesh.template elements<ELEM_ID>() | vcl::views::quality) {
        q = minQ + range * ((q - eMinQ) / (eMaxQ - eMinQ));
    }
}
 
template<MeshConcept MeshType, typename QualityType>
void setPerVertexQuality(MeshType& mesh, QualityType quality)
{
    setPerElementQuality<ElemId::VERTEX>(mesh, quality);
}
 
template<FaceMeshConcept MeshType, typename QualityType>
void setPerFaceQuality(MeshType& mesh, QualityType quality)
{
    setPerElementQuality<ElemId::FACE>(mesh, quality);
}
 
template<MeshConcept MeshType, typename QualityType>
void clampPerVertexQuality(MeshType& mesh, QualityType minQ, QualityType maxQ)
{
    clampPerElementQuality<ElemId::VERTEX>(mesh, minQ, maxQ);
}
 
template<FaceMeshConcept MeshType, typename QualityType>
void clampPerFaceQuality(MeshType& mesh, QualityType minQ, QualityType maxQ)
{
    clampPerElementQuality<ElemId::FACE>(mesh, minQ, maxQ);
}
 
template<MeshConcept MeshType, typename QualityType>
void normalizePerVertexQuality(
    MeshType&   mesh,
    QualityType minQ = 0,
    QualityType maxQ = 1)
{
    normalizePerElementQuality<ElemId::VERTEX>(mesh, minQ, maxQ);
}
 
template<FaceMeshConcept MeshType, typename QualityType>
void normalizePerFaceQuality(
    MeshType&   mesh,
    QualityType minQ = 0,
    QualityType maxQ = 1)
{
    normalizePerElementQuality<ElemId::FACE>(mesh, minQ, maxQ);
}
 
template<FaceMeshConcept MeshType>
void setPerVertexQualityFromVertexValence(MeshType& m)
{
    requirePerVertexQuality(m);
 
    using VertexType = MeshType::VertexType;
    using FaceType   = MeshType::FaceType;
 
    setPerVertexQuality(m, 0);
 
    for (FaceType& f : m.faces()) {
        for (VertexType* v : f.vertices()) {
            v->quality() += 1;
        }
    }
}
 
template<FaceMeshConcept MeshType>
void setPerFaceQualityFromFaceArea(MeshType& m)
{
    requirePerFaceQuality(m);
 
    using FaceType = MeshType::FaceType;
 
    for (FaceType& f : m.faces()) {
        f.quality() = faceArea(f);
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureGaussian(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
 
    for (VertexType& v : m.vertices()) {
        v.quality() = v.principalCurvature().maxValue() *
                      v.principalCurvature().minValue();
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureMean(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
 
    for (VertexType& v : m.vertices()) {
        v.quality() = (v.principalCurvature().maxValue() +
                       v.principalCurvature().minValue()) /
                      2;
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureMinValue(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
 
    for (VertexType& v : m.vertices()) {
        v.quality() = v.principalCurvature().minValue();
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureMaxValue(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
 
    for (VertexType& v : m.vertices()) {
        v.quality() = v.principalCurvature().maxValue();
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureShapeIndex(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
    using ScalarType = VertexType::PrincipalCurvatureType::ScalarType;
 
    for (VertexType& v : m.vertices()) {
        ScalarType k1 = v.principalCurvature().maxValue();
        ScalarType k2 = v.principalCurvature().minValue();
        if (k1 < k2)
            std::swap(k1, k2);
        v.quality() = (2.0 / M_PI) * std::atan2(k1 + k2, k1 - k2);
    }
}
 
template<MeshConcept MeshType>
void setPerVertexQualityFromPrincipalCurvatureCurvedness(MeshType& m)
{
    requirePerVertexQuality(m);
    requirePerVertexPrincipalCurvature(m);
 
    using VertexType = MeshType::VertexType;
    using ScalarType = VertexType::PrincipalCurvatureType::ScalarType;
 
    for (VertexType& v : m.vertices()) {
        ScalarType k1 = v.principalCurvature().maxValue();
        ScalarType k2 = v.principalCurvature().minValue();
 
        v.quality() = std::sqrt((k1 * k1 + k2 * k2) / 2.0);
    }
}
 
} // namespace vcl
 
#endif // VCL_ALGORITHMS_MESH_UPDATE_QUALITY_H