Description

A triangle mesh with connectivity info: vertices can be shared between faces.

#include <ChTriangleMeshConnected.h>

Inheritance diagram for chrono::geometry::ChTriangleMeshConnected:

Collaboration diagram for chrono::geometry::ChTriangleMeshConnected:

Classes
class	ChRefineEdgeCriterion
	Class to be used optionally in RefineMeshEdges(). More...

Public Member Functions
	ChTriangleMeshConnected (const ChTriangleMeshConnected &source)

virtual ChTriangleMeshConnected *	Clone () const override
	"Virtual" copy constructor (covariant return type).

std::vector< ChVector< double > > &	getCoordsVertices ()

std::vector< ChVector< double > > &	getCoordsNormals ()

std::vector< ChVector2< double > > &	getCoordsUV ()

std::vector< ChColor > &	getCoordsColors ()

std::vector< ChVector< int > > &	getIndicesVertexes ()

std::vector< ChVector< int > > &	getIndicesNormals ()

std::vector< ChVector< int > > &	getIndicesUV ()

std::vector< ChVector< int > > &	getIndicesColors ()

std::vector< int > &	getIndicesMaterials ()

bool	LoadWavefrontMesh (const std::string &filename, bool load_normals=true, bool load_uv=false)
	Load a Wavefront OBJ file into this triangle mesh.

virtual void	addTriangle (const ChVector<> &vertex0, const ChVector<> &vertex1, const ChVector<> &vertex2) override
	Add a triangle to this triangle mesh, by specifying the three coordinates. More...

virtual void	addTriangle (const ChTriangle &atriangle) override
	Add a triangle to this triangle mesh, by specifying a ChTriangle.

int	getNumVertices () const
	Get the number of vertices in this mesh.

int	getNumNormals () const
	Get the number of normals in this mesh.

virtual int	getNumTriangles () const override
	Get the number of triangles already added to this mesh.

virtual ChTriangle	getTriangle (int index) const override
	Access the n-th triangle in mesh.

virtual void	Clear () override
	Clear all data.

virtual void	GetBoundingBox (ChVector<> &cmin, ChVector<> &cmax, const ChMatrix33<> &rot) const override
	Compute bounding box along the directions defined by the given rotation matrix.

void	ComputeMassProperties (bool bodyCoords, double &mass, ChVector<> &center, ChMatrix33<> &inertia)
	Compute barycenter, mass, inertia tensor.

const std::string &	GetFileName () const
	Get the filename of the triangle mesh.

virtual void	Transform (const ChVector<> displ, const ChMatrix33<> rotscale) override
	Transform all vertexes, by displacing and rotating (rotation via matrix, so also scaling if needed).

bool	ComputeNeighbouringTriangleMap (std::vector< std::array< int, 4 >> &tri_map) const
	Create a map of neighboring triangles, vector [Ti TieA TieB TieC] (the free sides have triangle id = -1). More...

bool	ComputeWingedEdges (std::map< std::pair< int, int >, std::pair< int, int >> &winged_edges, bool allow_single_wing=true) const
	Create a winged edge structure, map of {key, value} as {{edgevertexA, edgevertexB}, {triangleA, triangleB}}. More...

int	RepairDuplicateVertexes (const double tolerance=1e-18)
	Connect overlapping vertexes. More...

bool	MakeOffset (const double offset)
	Offset the mesh, by a specified value, orthogonally to the faces. More...

std::pair< int, int >	GetTriangleEdgeIndexes (const ChVector< int > &face_indices, int nedge, bool unique)
	Return the indexes of the two vertexes of the i-th edge of the triangle. More...

bool	SplitEdge (int itA, int itB, int neA, int neB, int &itA_1, int &itA_2, int &itB_1, int &itB_2, std::vector< std::array< int, 4 >> &tri_map, std::vector< std::vector< double > * > &aux_data_double, std::vector< std::vector< int > * > &aux_data_int, std::vector< std::vector< bool > * > &aux_data_bool, std::vector< std::vector< ChVector<>> * > &aux_data_vect)
	Split a given edge by inserting a vertex in the middle: from two triangles one gets four triangles. More...

void	RefineMeshEdges (std::vector< int > &marked_tris, double edge_maxlen, ChRefineEdgeCriterion criterion, std::vector< std::array< int, 4 >> atri_map, std::vector< std::vector< double > * > &aux_data_double, std::vector< std::vector< int > * > &aux_data_int, std::vector< std::vector< bool > * > &aux_data_bool, std::vector< std::vector< ChVector<>> * > &aux_data_vect)
	Performs mesh refinement using Rivara LEPP long-edge bisection algorithm. More...

virtual GeometryType	GetClassType () const override
	Get the class type as unique numerical ID (faster than using ChronoRTTI mechanism). More...

virtual void	ArchiveOUT (ChArchiveOut &marchive) override
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIN (ChArchiveIn &marchive) override
	Method to allow de-serialization of transient data from archives.

Public Member Functions inherited from chrono::geometry::ChTriangleMesh
virtual void	Transform (const ChVector<> displ, const ChQuaternion<> mquat=ChQuaternion<>(1, 0, 0, 0))
	Transform all vertexes, by displacing and rotating (rotation via matrix, so also scaling if needed)

virtual int	GetManifoldDimension () const override
	This is a surface.

Public Member Functions inherited from chrono::geometry::ChGeometry
	ChGeometry (const ChGeometry &source)

void	InflateBoundingBox (ChVector<> &cmin, ChVector<> &cmax, const ChMatrix33<> &rot) const
	Enlarge the given existing bounding box with the bounding box of this object.

virtual double	GetBoundingSphereRadius () const
	Returns the radius of a bounding sphere for this geometry. More...

virtual ChVector	Baricenter () const
	Compute center of mass.

virtual void	Update ()
	Generic update of internal data.

Static Public Member Functions
static std::shared_ptr< ChTriangleMeshConnected >	CreateFromWavefrontFile (const std::string &filename, bool load_normals=true, bool load_uv=false)
	Create and return a ChTriangleMeshConnected from a Wavefront OBJ file. More...

static void	WriteWavefront (const std::string &filename, const std::vector< ChTriangleMeshConnected > &meshes)
	Write the specified meshes in a Wavefront .obj file.

static ChTriangleMeshConnected	Merge (std::vector< ChTriangleMeshConnected > &meshes)
	Utility function for merging multiple meshes.

Public Attributes
std::vector< ChVector< double > >	m_vertices

std::vector< ChVector< double > >	m_normals

std::vector< ChVector2< double > >	m_UV

std::vector< ChColor >	m_colors

std::vector< ChVector< int > >	m_face_v_indices

std::vector< ChVector< int > >	m_face_n_indices

std::vector< ChVector< int > >	m_face_uv_indices

std::vector< ChVector< int > >	m_face_col_indices

std::vector< int >	m_face_mat_indices

std::string	m_filename
	file string if loading an obj file

Additional Inherited Members
Public Types inherited from chrono::geometry::ChGeometry
enum	GeometryType { NONE, SPHERE, BOX, CYLINDER, TRIANGLE, CAPSULE, CONE, LINE, LINE_ARC, LINE_BEZIER, LINE_CAM, LINE_PATH, LINE_POLY, LINE_SEGMENT, ROUNDED_BOX, ROUNDED_CYLINDER, ROUNDED_CONE, TRIANGLEMESH, TRIANGLEMESH_CONNECTED, TRIANGLEMESH_SOUP }
	Enumeration of geometric objects.

Member Function Documentation

◆ addTriangle()

void chrono::geometry::ChTriangleMeshConnected::addTriangle	(	const ChVector<> &	vertex0,
		const ChVector<> &	vertex1,
		const ChVector<> &	vertex2
	)

overridevirtual

Add a triangle to this triangle mesh, by specifying the three coordinates.

This is disconnected - no vertex sharing is used even if it could be.

Implements chrono::geometry::ChTriangleMesh.

◆ ComputeNeighbouringTriangleMap()

bool chrono::geometry::ChTriangleMeshConnected::ComputeNeighbouringTriangleMap ( std::vector< std::array< int, 4 >> & tri_map ) const

Create a map of neighboring triangles, vector [Ti TieA TieB TieC] (the free sides have triangle id = -1).

Return false if some edge has more than 2 neighboring triangles

◆ ComputeWingedEdges()

bool chrono::geometry::ChTriangleMeshConnected::ComputeWingedEdges	(	std::map< std::pair< int, int >, std::pair< int, int >> &	winged_edges,
		bool	allow_single_wing = `true`
	)		const

Create a winged edge structure, map of {key, value} as {{edgevertexA, edgevertexB}, {triangleA, triangleB}}.

If allow_single_wing = false, only edges with at least 2 triangles are returned. Else, also boundary edges with 1 triangle (the free side has triangle id = -1). Return false if some edge has more than 2 neighboring triangles.

◆ CreateFromWavefrontFile()

std::shared_ptr< ChTriangleMeshConnected > chrono::geometry::ChTriangleMeshConnected::CreateFromWavefrontFile	(	const std::string &	filename,
		bool	load_normals = `true`,
		bool	load_uv = `false`
	)

static

Create and return a ChTriangleMeshConnected from a Wavefront OBJ file.

If an error occurrs during loading, an empty shared pointer is returned.

◆ GetClassType()

virtual GeometryType chrono::geometry::ChTriangleMeshConnected::GetClassType ( ) const

inlineoverridevirtual

Get the class type as unique numerical ID (faster than using ChronoRTTI mechanism).

Each inherited class must return an unique ID.

Reimplemented from chrono::geometry::ChTriangleMesh.

◆ GetTriangleEdgeIndexes()

std::pair< int, int > chrono::geometry::ChTriangleMeshConnected::GetTriangleEdgeIndexes	(	const ChVector< int > &	face_indices,
		int	nedge,
		bool	unique
	)

Return the indexes of the two vertexes of the i-th edge of the triangle.

If unique=true, swap the pair so that 1st < 2nd, to permit test sharing with other triangle.

Parameters

face_indices	indices of a triangular face
nedge	number of edge: 0, 1, 2
unique	swap?

◆ MakeOffset()

bool chrono::geometry::ChTriangleMeshConnected::MakeOffset ( const double offset )

Offset the mesh, by a specified value, orthogonally to the faces.

The offset can be inward or outward. Note: self-collisions and inverted faces resulting from excessive offsets are NOT trimmed; so this is mostly meant to be a fast tool for making small offsets.

◆ RefineMeshEdges()

void chrono::geometry::ChTriangleMeshConnected::RefineMeshEdges	(	std::vector< int > &	marked_tris,
		double	edge_maxlen,
		ChRefineEdgeCriterion *	criterion,
		std::vector< std::array< int, 4 >> *	atri_map,
		std::vector< std::vector< double > * > &	aux_data_double,
		std::vector< std::vector< int > * > &	aux_data_int,
		std::vector< std::vector< bool > * > &	aux_data_bool,
		std::vector< std::vector< ChVector<>> * > &	aux_data_vect
	)

Performs mesh refinement using Rivara LEPP long-edge bisection algorithm.

Given a conforming, non-degenerate triangulation, it construct a locally refined triangulation with a prescribed resolution. This algorithm, for increasing resolution, tends to produce triangles with bounded angles even if starting from skewed/skinny triangles in the coarse mesh. Based on "Multithread parallelization of Lepp-bisection algorithms" M.-C. Rivara et al., Applied Numerical Mathematics 62 (2012) 473�488 The auxiliary buffers are used for refinement and assumed to be indexed like the vertex buffer.

Parameters

marked_tris	indexes of triangles to refine (also surrounding triangles might be affected by refinements)
edge_maxlen	maximum length of edge (small values give higher resolution)
criterion	criterion for computing lenght (or other merit function) of edge, if null uses default (euclidean length)
atri_map	optional triangle connectivity map
aux_data_double	auxiliary buffer
aux_data_int	auxiliary buffer
aux_data_bool	auxiliary buffer
aux_data_vect	auxiliary buffer

◆ RepairDuplicateVertexes()

int chrono::geometry::ChTriangleMeshConnected::RepairDuplicateVertexes ( const double tolerance = 1e-18 )

Connect overlapping vertexes.

This can beused to attempt to repair a mesh with 'open edges' to transform it into a watertight mesh. Say, if a cube is modeled with 6 faces with 4 distinct vertexes each, it might display properly, but for some algorithms, ex. collision detection, topological information might be needed, hence adjacent faces must be connected. Return the number of merged vertexes.

Parameters

tolerance when vertexes are closer than this value, they are merged

◆ SplitEdge()

bool chrono::geometry::ChTriangleMeshConnected::SplitEdge	(	int	itA,
		int	itB,
		int	neA,
		int	neB,
		int &	itA_1,
		int &	itA_2,
		int &	itB_1,
		int &	itB_2,
		std::vector< std::array< int, 4 >> &	tri_map,
		std::vector< std::vector< double > * > &	aux_data_double,
		std::vector< std::vector< int > * > &	aux_data_int,
		std::vector< std::vector< bool > * > &	aux_data_bool,
		std::vector< std::vector< ChVector<>> * > &	aux_data_vect
	)

Split a given edge by inserting a vertex in the middle: from two triangles one gets four triangles.

It also interpolate normals, colors, uv. It also used and modifies the triangle neighboring map. If the two triangles do not share an edge, returns false. The auxiliary buffers are used for interpolation and assumed to be indexed like the vertex buffer.

Parameters

itA	triangle A index,
itB	triangle B index, -1 if not present (free edge on A)
neA	n.edge on tri A: 0,1,2
neB	n.edge on tri B: 0,1,2
itA_1	returns the index of split triangle A, part1
itA_2	returns the index of split triangle A, part2
itB_1	returns the index of split triangle B, part1
itB_2	returns the index of split triangle B, part2
tri_map	triangle neighbouring map
aux_data_double	auxiliary buffers
aux_data_int	auxiliary buffers
aux_data_bool	auxiliary buffers
aux_data_vect	auxiliary buffers

The documentation for this class was generated from the following files:

/builds/uwsbel/chrono/src/chrono/geometry/ChTriangleMeshConnected.h
/builds/uwsbel/chrono/src/chrono/geometry/ChTriangleMeshConnected.cpp

Description

Classes

Public Member Functions

Static Public Member Functions

Public Attributes

Additional Inherited Members

Member Function Documentation

◆ addTriangle()

◆ ComputeNeighbouringTriangleMap()

◆ ComputeWingedEdges()

◆ CreateFromWavefrontFile()

◆ GetClassType()

◆ GetTriangleEdgeIndexes()

◆ MakeOffset()

◆ RefineMeshEdges()

◆ RepairDuplicateVertexes()

◆ SplitEdge()