Meshes a single triangle with the constraints that come from the intersections with the other triangles. More...

#include <geogram/mesh/mesh_surface_intersection_internal.h>

Inheritance diagram for GEO::MeshInTriangle:

Classes
class	Edge
	An edge of the mesh. More...

class	Vertex
	A vertex of the triangulation. More...

Public Types
typedef exact::vec3h	ExactPoint

Public Member Functions
	MeshInTriangle (MeshSurfaceIntersection &EM)

const Mesh &	mesh () const
	Gets the readonly initial mesh.

Mesh &	target_mesh ()
	Gets the target mesh.

void	set_dry_run (bool x)
	In dry run mode, the computed local triangulations are not inserted in the global mesh. This is for benchmarking. Default is off.

void	save_constraints (const std::string &filename)
	For debugging, save constraints to a file.

void	begin_facet (index_t f)

index_t	add_vertex (index_t f2, TriangleRegion R1, TriangleRegion R2)

void	add_edge (index_t f2, TriangleRegion AR1, TriangleRegion AR2, TriangleRegion BR1, TriangleRegion BR2)

void	commit ()
	Creates new vertices and new triangles in target mesh.

void	clear () override

void	save (const std::string &filename) const override
	Saves this CDT to a geogram mesh file.

Public Member Functions inherited from GEO::CDTBase2d
	CDTBase2d ()
	CDTBase2d constructor.

virtual	~CDTBase2d ()
	CDTBase2d destructor.

void	insert_constraint (index_t i, index_t j)
	Inserts a constraint.

void	remove_external_triangles (bool remove_internal_holes=false)
	Recursively removes all the triangles adjacent to the border, and keeps what's surrounded by constraints.

void	set_delaunay (bool delaunay)
	Specifies whether a constrained Delaunay triangulation should be constructed, or just a plain constrained triangulation.

index_t	nT () const
	Gets the number of triangles.

index_t	nv () const
	Gets the number of vertices.

index_t	ncnstr () const
	Gets the number of constraints.

index_t	Tv (index_t t, index_t lv) const
	Gets a vertex of a triangle.

index_t	Tv_find (index_t t, index_t v) const
	Finds the local index of a vertex in a triangle.

index_t	Tadj (index_t t, index_t le) const
	Gets a triangle adjacent to a triangle.

index_t	Tadj_find (index_t t1, index_t t2) const
	Finds the edge accross which a triangle is adjacent to another one.

index_t	vT (index_t v) const
	Gets a triangle incident to a given vertex.

index_t	Tedge_cnstr_first (index_t t, index_t le) const
	Gets the constraint associated with an edge.

index_t	edge_cnstr_next (index_t ecit) const
	Gets the successor of an edge constraint iterator.

index_t	edge_cnstr (index_t ecit) const
	Gets an edge constraint from an edge constraint iterator.

index_t	Tedge_cnstr_nb (index_t t, index_t le) const
	Gets the number of constraints associated with a triange edge.

bool	Tedge_is_Delaunay (index_t t, index_t le) const
	Tests whether a triangle edge is Delaunay.

void	check_consistency () const
	Checks both combinatorics and geometry, aborts on unconsistency.

Protected Member Functions
void	get_constraints (Mesh &M, bool with_edges=true) const
	For debugging, copies the constraints to a mesh.

vec3	mesh_vertex (index_t v) const

vec3	mesh_facet_vertex (index_t f, index_t lv) const

vec2	mesh_vertex_UV (index_t v) const

vec2	mesh_facet_vertex_UV (index_t f, index_t lv) const

void	log_err () const

Sign	orient2d (index_t v1, index_t v2, index_t v3) const override
	Tests the orientation of three vertices.

Sign	incircle (index_t v1, index_t v2, index_t v3, index_t v4) const override
	Tests the relative position of a point with respect to the circumscribed circle of a triangle.

index_t	create_intersection (index_t e1, index_t i, index_t j, index_t e2, index_t k, index_t l) override
	Given two segments that have an intersection, create the intersection.

void	get_edge_edge_intersection (index_t e1, index_t e2, ExactPoint &I) const
	Computes the intersection between two edges.

void	get_edge_edge_intersection_2D (index_t e1, index_t e2, ExactPoint &I) const
	Auxilliary function used by get_edge_edge_intersection() for the special case when the two edges are coplanar.

void	begin_insert_transaction () override

void	commit_insert_transaction () override

void	rollback_insert_transaction () override

Protected Member Functions inherited from GEO::CDTBase2d
index_t	insert (index_t v, index_t hint=NO_INDEX)
	Inserts a new point.

void	create_enclosing_triangle (index_t v1, index_t v2, index_t v3)
	Creates the combinatorics for a first large enclosing triangle.

void	create_enclosing_quad (index_t v1, index_t v2, index_t v3, index_t v4)
	Creates the combinatorics for a first large enclosing quad.

void	Tset_flag (index_t t, index_t flag)
	Sets a triangle flag.

void	Treset_flag (index_t t, index_t flag)
	Resets a triangle flag.

bool	Tflag_is_set (index_t t, index_t flag)
	Tests a triangle flag.

bool	Tis_in_list (index_t t) const
	Tests whether a triangle is in a DList.

void	insert_vertex_in_edge (index_t v, index_t t, index_t le, DList &S)
	Inserts a vertex in an edge.

void	insert_vertex_in_edge (index_t v, index_t t, index_t le)
	Inserts a vertex in an edge.

void	insert_vertex_in_triangle (index_t v, index_t t, DList &S)
	Inserts a vertex in a triangle.

index_t	find_intersected_edges (index_t i, index_t j, DList &Q)
	Finds the edges intersected by a constraint.

void	walk_constraint_v (CDT2d_ConstraintWalker &W)
	Used by find_intersected_edges()

void	walk_constraint_t (CDT2d_ConstraintWalker &W, DList &Q)
	Used by find_intersected_edges()

void	constrain_edges (index_t i, index_t j, DList &Q, DList &N)
	Constrains an edge by iteratively flipping the intersected edges.

void	Delaunayize_vertex_neighbors (index_t from_v)
	Restores Delaunay condition starting from the triangles incident to a given vertex.

void	Delaunayize_vertex_neighbors (index_t v, DList &S)
	Restores Delaunay condition starting from the triangles incident to a given vertex.

void	Delaunayize_new_edges (DList &N)
	Restores Delaunay condition for a set of edges after inserting a constrained edge.

void	Tset (index_t t, index_t v1, index_t v2, index_t v3, index_t adj1, index_t adj2, index_t adj3, index_t e1cnstr=NO_INDEX, index_t e2cnstr=NO_INDEX, index_t e3cnstr=NO_INDEX)
	Sets all the combinatorial information of a triangle and edge flags.

void	Trot (index_t t, index_t lv)
	Rotates indices in triangle t in such a way that a given vertex becomes vertex 0.

void	swap_edge (index_t t1, bool swap_t1_t2=false)
	Swaps an edge.

void	Tadj_set (index_t t, index_t le, index_t adj)
	Sets a triangle adjacency relation.

index_t	Topp (index_t t, index_t e=0) const
	Gets the neighboring triangle vertex opposite to a given vertex.

void	Tadj_back_connect (index_t t1, index_t le1, index_t prev_t2_adj_e2)
	After having changed connections from triangle to a neighbor, creates connections from neighbor to triangle.

index_t	Tnew ()
	Creates a new triangle.

void	Tset_edge_cnstr_first (index_t t, index_t le, index_t ecit)
	Sets the constraints list associated with an edge.

void	Tadd_edge_cnstr (index_t t, index_t le, index_t cnstr_id)
	Adds a constraint to a triangle edge.

void	Tadd_edge_cnstr_with_neighbor (index_t t, index_t le, index_t cnstr_id)
	Adds a constraint to a triangle edge and to the neighboring edge if it exists.

bool	Tedge_is_constrained (index_t t, index_t le) const
	Tests whether an edge is constrained.

void	for_each_T_around_v (index_t v, std::function< bool(index_t t, index_t lv)> doit)
	Calls a user-defined function for each triangle around a vertex.

index_t	locate (index_t v, index_t hint=NO_INDEX, Sign *orient=nullptr) const
	Locates a vertex.

bool	is_convex_quad (index_t t) const
	Tests whether triange t and its neighbor accross edge 0 form a strictly convex quad.

void	remove_marked_triangles ()
	Removes all the triangles that have the flag T_MARKED_FLAG set.

void	Tcheck (index_t t) const
	Consistency check for a triangle.

void	debug_Tcheck (index_t t) const
	Consistency check for a triangle in debug mode, ignored in release mode.

void	check_combinatorics () const
	Consistency combinatorial check for all the triangles.

void	debug_check_combinatorics () const
	Consistency combinatorial check for all the triangles in debug mode, ignored in release mode.

virtual void	check_geometry () const
	Consistency geometrical check for all the triangles.

void	debug_check_geometry () const
	Consistency geometrical check for all the triangles in debug mode, ignored in release mode.

void	debug_check_consistency () const
	Checks both combinatorics and geometry in debug mode, ignored in release mode, aborts on unconsistency.

bool	segment_segment_intersect (index_t u1, index_t u2, index_t v1, index_t v2) const
	Tests whether two segments have a frank intersection.

bool	segment_edge_intersect (index_t v1, index_t v2, index_t t, index_t le) const
	Tests whether an edge triangle and a segment have a frank intersection.

void	check_edge_intersections (index_t v1, index_t v2, const DList &Q)
	Checks that the edges stored in a DList exactly correspond to all edge intersections between a segment and the triangle edges.

index_t	eT (Edge E)
	Gets a triangle incident a a given edge.

index_t	locate_naive (index_t v, index_t hint=NO_INDEX, Sign *orient=nullptr) const
	Simpler version of locate() kept for reference.

void	constrain_edges_naive (index_t i, index_t j, DList &Q, vector< Edge > &N)
	Simpler version of constrain_edges() kept for reference.

void	Delaunayize_new_edges_naive (vector< Edge > &N)
	Simpler version of Delaunayize_new_edges() that uses a vector instead of a DList, kept for reference.

Additional Inherited Members
Protected Types inherited from GEO::CDTBase2d
enum	{ DLIST_S_ID =0 , DLIST_Q_ID =1 , DLIST_N_ID =2 , DLIST_NB =3 }
	Constants for list_id. More...

enum	{ T_MARKED_FLAG = DLIST_NB , T_VISITED_FLAG = DLIST_NB+1 }
	Constants for triangle flags. More...

typedef std::pair< index_t, index_t >	Edge

Static Protected Member Functions inherited from GEO::CDTBase2d
static index_t	find_3 (const index_t *T, index_t v)
	Finds the index of an integer in an array of three integers.

Protected Attributes inherited from GEO::CDTBase2d
index_t	nv_

index_t	ncnstr_

vector< index_t >	T_

vector< index_t >	Tadj_

vector< index_t >	v2T_

vector< uint8_t >	Tflags_

vector< index_t >	Tecnstr_first_

vector< index_t >	ecnstr_val_

vector< index_t >	ecnstr_next_

vector< index_t >	Tnext_

vector< index_t >	Tprev_

bool	delaunay_

Sign	orient_012_

bool	exact_incircle_

bool	exact_intersections_

Detailed Description

Meshes a single triangle with the constraints that come from the intersections with the other triangles.

Inherits CDTBase2d (constrained Delaunay triangulation), and redefines orient2d(), incircle2d() and create_intersection() using vectors with homogeneous coordinates stored as arithmetic expansions (vec2HE) or arbitrary-precision floating point numbers (vec2HEx) if compiled with Tessael's geogramplus extension package.

Definition at line 70 of file mesh_surface_intersection_internal.h.

Member Typedef Documentation

◆ ExactPoint

typedef exact::vec3h GEO::MeshInTriangle::ExactPoint

Definition at line 73 of file mesh_surface_intersection_internal.h.

Member Function Documentation

◆ begin_insert_transaction()

void GEO::MeshInTriangle::begin_insert_transaction ( )

overrideprotectedvirtual

Reimplemented from GEO::CDTBase2d.

◆ clear()

void GEO::MeshInTriangle::clear ( )

overridevirtual

See also: CDT2d::clear()

Reimplemented from GEO::CDTBase2d.

◆ commit_insert_transaction()

void GEO::MeshInTriangle::commit_insert_transaction ( )

overrideprotectedvirtual

Reimplemented from GEO::CDTBase2d.

◆ create_intersection()

index_t GEO::MeshInTriangle::create_intersection	(	index_t	e1,
		index_t	i,
		index_t	j,
		index_t	e2,
		index_t	k,
		index_t	l
	)

overrideprotectedvirtual

Given two segments that have an intersection, create the intersection.

The intersection is given both as the indices of segment extremities (i,j) and (k,l), that one can use to retreive the points in derived classes, and constraint indices E1 and E2, that derived classes may use to retreive symbolic information attached to the constraint

Parameters

[in]	e1	the index of the first edge, corresponding to the value of ncnstr() when insert_constraint() was called for that edge
[in]	i,j	the vertices of the first segment
[in]	e2	the index of the second edge, corresponding to the value of ncnstr() when insert_constraint() was called for that edge
[in]	k,l	the vertices of the second segment

Returns: the index of a newly created vertex that corresponds to the intersection between [i , j] and [k , l]

Implements GEO::CDTBase2d.

◆ get_edge_edge_intersection()

void GEO::MeshInTriangle::get_edge_edge_intersection	(	index_t	e1,
		index_t	e2,
		ExactPoint &	I
	)		const

protected

Computes the intersection between two edges.

Parameters

[in]	e1,e2	the two edges
[out]	I	the intersection

◆ get_edge_edge_intersection_2D()

void GEO::MeshInTriangle::get_edge_edge_intersection_2D	(	index_t	e1,
		index_t	e2,
		ExactPoint &	I
	)		const

protected

Auxilliary function used by get_edge_edge_intersection() for the special case when the two edges are coplanar.

Parameters

[in]	e1,e2	the two edges
[out]	I	the intersection

◆ incircle()

Sign GEO::MeshInTriangle::incircle	(	index_t	v1,
		index_t	v2,
		index_t	v3,
		index_t	v4
	)		const

overrideprotectedvirtual

Tests the relative position of a point with respect to the circumscribed circle of a triangle.

Parameters

[in]	v1,v2,v3	the three vertices of the triangle oriented anticlockwise
[in]	v4	the point to be tested

Return values

POSITIVE	if the point is inside the circle
ZERO	if the point is on the circle
NEGATIVE	if the point is outside the circle

Implements GEO::CDTBase2d.

◆ log_err()

void GEO::MeshInTriangle::log_err ( ) const

inlineprotected

Definition at line 340 of file mesh_surface_intersection_internal.h.

◆ mesh()

const Mesh & GEO::MeshInTriangle::mesh ( ) const

inline

Gets the readonly initial mesh.

Returns: a const reference to a copy of the initial mesh

Definition at line 261 of file mesh_surface_intersection_internal.h.

◆ mesh_facet_vertex()

vec3 GEO::MeshInTriangle::mesh_facet_vertex	(	index_t	f,
		index_t	lv
	)		const

inlineprotected

Definition at line 324 of file mesh_surface_intersection_internal.h.

◆ mesh_facet_vertex_UV()

vec2 GEO::MeshInTriangle::mesh_facet_vertex_UV	(	index_t	f,
		index_t	lv
	)		const

inlineprotected

Definition at line 334 of file mesh_surface_intersection_internal.h.

◆ mesh_vertex()

vec3 GEO::MeshInTriangle::mesh_vertex ( index_t v ) const

inlineprotected

Definition at line 320 of file mesh_surface_intersection_internal.h.

◆ mesh_vertex_UV()

vec2 GEO::MeshInTriangle::mesh_vertex_UV ( index_t v ) const

inlineprotected

Definition at line 329 of file mesh_surface_intersection_internal.h.

◆ orient2d()

Sign GEO::MeshInTriangle::orient2d	(	index_t	v1,
		index_t	v2,
		index_t	v3
	)		const

overrideprotectedvirtual

Tests the orientation of three vertices.

Parameters

[in] v1,v2,v3 the three vertices

Return values

POSITIVE	if they are in the trigonometric order
ZERO	if they are aligned
NEGATIVE	if they are in the anti-trigonometric order

Implements GEO::CDTBase2d.

◆ rollback_insert_transaction()

void GEO::MeshInTriangle::rollback_insert_transaction ( )

overrideprotectedvirtual

Reimplemented from GEO::CDTBase2d.

◆ save()

void GEO::MeshInTriangle::save ( const std::string & filename ) const

overridevirtual

Saves this CDT to a geogram mesh file.

Parameters

[in] filename where to save this CDT

Implements GEO::CDTBase2d.

◆ save_constraints()

void GEO::MeshInTriangle::save_constraints ( const std::string & filename )

inline

For debugging, save constraints to a file.

Parameters

[in] filename a mesh filename where to solve the constraints (.obj or .geogram)

Definition at line 287 of file mesh_surface_intersection_internal.h.

◆ set_dry_run()

void GEO::MeshInTriangle::set_dry_run ( bool x )

inline

In dry run mode, the computed local triangulations are not inserted in the global mesh. This is for benchmarking. Default is off.

Definition at line 278 of file mesh_surface_intersection_internal.h.

◆ target_mesh()

Mesh & GEO::MeshInTriangle::target_mesh ( )

inline

Gets the target mesh.

Returns: a reference to the target mesh

Definition at line 269 of file mesh_surface_intersection_internal.h.

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

geogram/mesh/mesh_surface_intersection_internal.h

Classes

Public Types

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ ExactPoint

Member Function Documentation

◆ begin_insert_transaction()

◆ clear()

◆ commit_insert_transaction()

◆ create_intersection()

◆ get_edge_edge_intersection()

◆ get_edge_edge_intersection_2D()

◆ incircle()

◆ log_err()

◆ mesh()

◆ mesh_facet_vertex()

◆ mesh_facet_vertex_UV()

◆ mesh_vertex()

◆ mesh_vertex_UV()

◆ orient2d()

◆ rollback_insert_transaction()

◆ save()

◆ save_constraints()

◆ set_dry_run()

◆ target_mesh()