OpenMesh
ModNormalFlippingT.hh
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48//=============================================================================
49//
50// CLASS ModNormalFlipping
51//
52//=============================================================================
53
54
55#ifndef OPENMESH_DECIMATER_MODNORMALFLIPPING_HH
56#define OPENMESH_DECIMATER_MODNORMALFLIPPING_HH
57
58
59//== INCLUDES =================================================================
60
62
63//== NAMESPACES ===============================================================
64
65namespace OpenMesh { // BEGIN_NS_OPENMESH
66namespace Decimater { // BEGIN_NS_DECIMATER
67
68
69//== CLASS DEFINITION =========================================================
70
79template <typename MeshT>
80class ModNormalFlippingT : public ModBaseT< MeshT >
81{
82public:
83
84 DECIMATING_MODULE( ModNormalFlippingT, MeshT, NormalFlipping );
85
86public:
87
89 explicit ModNormalFlippingT( MeshT &_mesh) : Base(_mesh, true)
90 {
92 const bool mesh_has_normals = _mesh.has_face_normals();
93 _mesh.request_face_normals();
94
95 if (!mesh_has_normals)
96 {
97 omerr() << "Mesh has no face normals. Compute them automatically." << std::endl;
98 _mesh.update_face_normals();
99 }
100 }
101
102
104 {
105 Base::mesh().release_face_normals();
106 }
107
108
109public:
110
125 float collapse_priority(const CollapseInfo& _ci) override
126 {
127 // simulate collapse
128 Base::mesh().set_point(_ci.v0, _ci.p1);
129
130 // check for flipping normals
131 typename Mesh::ConstVertexFaceIter vf_it(Base::mesh(), _ci.v0);
132 typename Mesh::FaceHandle fh;
133 typename Mesh::Scalar c(1.0);
134
135 for (; vf_it.is_valid(); ++vf_it)
136 {
137 fh = *vf_it;
138 if (fh != _ci.fl && fh != _ci.fr)
139 {
140 typename Mesh::Normal n1 = Base::mesh().normal(fh);
141 typename Mesh::Normal n2 = Base::mesh().calc_face_normal(fh);
142
143 c = dot(n1, n2);
144
145 if (c < min_cos_)
146 break;
147 }
148 }
149
150 // undo simulation changes
151 Base::mesh().set_point(_ci.v0, _ci.p0);
152
153 return float( (c < min_cos_) ? Base::ILLEGAL_COLLAPSE : Base::LEGAL_COLLAPSE );
154 }
155
157 void set_error_tolerance_factor(double _factor) override {
158 if (_factor >= 0.0 && _factor <= 1.0) {
159 // the smaller the factor, the smaller max_deviation_ gets
160 // thus creating a stricter constraint
161 // division by error_tolerance_factor_ is for normalization
162 double max_normal_deviation_value = (max_deviation_ * 180.0/M_PI) * _factor / this->error_tolerance_factor_;
163 set_max_normal_deviation(max_normal_deviation_value);
164 this->error_tolerance_factor_ = _factor;
165 }
166 }
167
168
169public:
170
172 double max_normal_deviation() const { return max_deviation_ / M_PI * 180.0; }
173
179 void set_max_normal_deviation(double _d) {
180 max_deviation_ = _d / 180.0 * M_PI;
181 min_cos_ = cos(max_deviation_);
182 }
183
184private:
185
186 // maximum normal deviation
187 double max_deviation_, min_cos_;
188};
189
190
191//=============================================================================
192} // END_NS_DECIMATER
193} // END_NS_OPENMESH
194//=============================================================================
195#endif // OPENMESH_DECIMATER_MODNORMALFLIPPING_HH defined
196//=============================================================================
197
Base class for all decimation modules.
#define DECIMATING_MODULE(Classname, MeshT, Name)
Convenience macro, to be used in derived modules The macro defines the types.
Definition: ModBaseT.hh:149
Contains all the mesh ingredients like the polygonal mesh, the triangle mesh, different mesh kernels ...
Definition: MeshItems.hh:59
osg::Vec3f::ValueType dot(const osg::Vec3f &_v1, const osg::Vec3f &_v2)
Adapter for osg vector member computing a scalar product.
Definition: VectorAdapter.hh:176
Kernel::Scalar Scalar
Scalar type.
Definition: PolyMeshT.hh:110
Kernel::Normal Normal
Normal type.
Definition: PolyMeshT.hh:114
Kernel::ConstVertexFaceIter ConstVertexFaceIter
Circulator.
Definition: PolyMeshT.hh:176
Kernel::FaceHandle FaceHandle
Scalar type.
Definition: PolyMeshT.hh:139
Stores information about a halfedge collapse.
Definition: CollapseInfoT.hh:74
Mesh::FaceHandle fr
Right face.
Definition: CollapseInfoT.hh:87
Mesh::Point p0
Position of removed vertex.
Definition: CollapseInfoT.hh:84
Mesh::Point p1
Positions of remaining vertex.
Definition: CollapseInfoT.hh:85
Mesh::VertexHandle v0
Vertex to be removed.
Definition: CollapseInfoT.hh:82
Mesh::FaceHandle fl
Left face.
Definition: CollapseInfoT.hh:86
Base class for all decimation modules.
Definition: ModBaseT.hh:193
Decimating module to avoid flipping of faces.
Definition: ModNormalFlippingT.hh:81
double max_normal_deviation() const
get normal deviation
Definition: ModNormalFlippingT.hh:172
ModNormalFlippingT(MeshT &_mesh)
Constructor.
Definition: ModNormalFlippingT.hh:89
void set_error_tolerance_factor(double _factor) override
set the percentage of maximum normal deviation
Definition: ModNormalFlippingT.hh:157
float collapse_priority(const CollapseInfo &_ci) override
Compute collapse priority due to angular deviation of face normals before and after a collapse.
Definition: ModNormalFlippingT.hh:125
void set_max_normal_deviation(double _d)
Set normal deviation.
Definition: ModNormalFlippingT.hh:179

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