jv.geom

Class PuCleanMesh

java.lang.Object

jv.geom.PuCleanMesh

public class PuCleanMesh
extends java.lang.Object

Utility programs for identification of equal vertices and other cleaning operations.

Author:

Konrad Polthier, Ulrich Reitebuch

Version:

06.10.03, 3.00 created (kp) Class created from a subset of methods of jvx.geom.PwCleanMesh.
07.02.02, 2.00 revised (ur) IdentifyVertices and removeDegenerateElements maintain Neighbourhoods.
21.12.01, 1.90 revised (ur) Identify Vertices enabled for PointSet, Polygon and PolygonSet.
06.06.01, 1.70 revised (ur) RemoveDegenerateElements method improved.
15.06.00, 1.20 revised (kp) Added method identifyVertices().
27.04.00, 1.10 revised (kp) Method adapt() moved from PgElementSet into this workshop.
25.01.00, 1.00 created (ur) Original class jvx.geom.PwCleanMesh.

Constructor Summary

Constructors

Constructor and Description
PuCleanMesh()

Method Summary

Modifier and Type	Method and Description
static int	getNumDegenerateElements(PgElementSet geom) Count degenerated elements. degenerated are elements, which do not have pairwise distinct vertices or element with less than three vertices.
static int	identifyVertices(PgGeometry geom) Identify vertices which are identical.
static int	identifyVertices(PgPointSet geom, double eps) Identify vertices which are within an epsilon box of each other.
static int	identifyVertices(PgPointSet geom, double eps, boolean bMarked) Identify vertices which are within an epsilon box of each other.
static void	removeDegenerateElements(PgElementSet geom) Adapt triangulation to the following conventions: - the vertices of an element must be pairwise different

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PuCleanMesh

public PuCleanMesh()

Method Detail

identifyVertices

public static int identifyVertices(PgGeometry geom)

Identify vertices which are identical. Vertices are first sorted along the diagonal of the bounding box to accelerate the comparison.

Vertex normals are recomputed if previously available and a positive number of vertices were removed.

Method is applicable to PgPointSet and its subclasses.

Parameters:

geom - Geometry whose vertices shall be identified

Returns:

number of removed vertices

See Also:

identifyVertices(PgPointSet, double)

Author:

Konrad Polthier

Version:

25.10.04, 1.10 revised (kp) Recompute vertex normals if previously available.
06.10.03, 1.00 created (kp)

identifyVertices

public static int identifyVertices(PgPointSet geom,
                                   double eps)

Identify vertices which are within an epsilon box of each other. Vertices are first sorted along the diagonal of the bounding box to accelerate the comparison.

Parameters:

geom - Geometry whose vertices shall be identified

eps - tolerance of coordinate components, not distance

Returns:

number of removed vertices

See Also:

identifyVertices(PgGeometry), identifyVertices(PgPointSet, double, boolean)

Author:

Konrad Polthier

Version:

15.06.00, 1.00 created (kp) Method calls #identifyVertices(PgPointSet,double,false).

identifyVertices

public static int identifyVertices(PgPointSet geom,
                                   double eps,
                                   boolean bMarked)

Identify vertices which are within an epsilon box of each other. The new position of joined vertices is the average of the old ones. Vertices are first sorted along the diagonal of the bounding box to accelerate the comparison.

If flag bMarked is true then nearby vertices are identified only if both of the vertices are marked. This allows to perform identification only on a selected set of vertices.

Parameters:

geom - Geometry whose vertices shall be identified

eps - tolerance of coordinate components, not distance

bMarked - flag if identification is only performed on selected set of vertices

Returns:

number of removed vertices

See Also:

identifyVertices(PgPointSet, double)

Author:

Konrad Polthier

Version:

04.06.07, 2.20 revised (fk) New position of joined vertices is now average of old ones.
14.03.05, 2.10 revised (kp) Recompute vertex normals if initially existing.
13.08.04, 2.00 revised (kp) Additional parameter bMarked added.
20.03.03, 1.80 revised (ep) Check for (numVertices < 2).
19.05.02, 1.70 revised (kp) Sort vertices first along diagonal of bounding box.
20.12.01, 1.60 revised (ur) Extended to handle different types of geometries.
01.03.01, 1.50 revised (kp) Use heapsort to reduce complexity of method.
15.06.00, 1.00 created (kp)

getNumDegenerateElements

public static int getNumDegenerateElements(PgElementSet geom)

Count degenerated elements. degenerated are elements, which do not have pairwise distinct vertices or element with less than three vertices.

Author:

Ulrich Reitebuch

Version:

14.08.06, 1.00 created (ur)

removeDegenerateElements

public static void removeDegenerateElements(PgElementSet geom)

Adapt triangulation to the following conventions: - the vertices of an element must be pairwise different. - every element has at least three vertices.

Author:

Ulrich Reitebuch

Version:

14.08.06, 1.30 revised (ur) Maintain element textures, normals and vector fields.
30.01.02, 1.20 revised (ur) Maintain neighbourhood informations.
06.06.01, 1.10 revised (ur) Divide elements with not subsequent equal vertices.
25.01.00, 1.00 created (ur)