maspack.collision

Class IntersectionContour

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractList<E>

java.util.ArrayList<IntersectionPoint>

maspack.collision.IntersectionContour

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Iterable<IntersectionPoint>, java.util.Collection<IntersectionPoint>, java.util.List<IntersectionPoint>, java.util.RandomAccess

public class IntersectionContour
extends java.util.ArrayList<IntersectionPoint>

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
Face	containingFace
boolean	isClosed
boolean	isContinuable
boolean	openMesh
double	singleFaceArea

Constructor Summary

Constructors

Constructor and Description
IntersectionContour()

Method Summary

Modifier and Type	Method and Description
void	computeCentroid(Vector3d centroid) Computes the centroid of this contour, rejecting points that are very close together.
double	computeLength() Computes the length of this contour
double	computePlanarArea() Computes the area of this contour with respect to a plane formed by computing the centroid and then summing the cross products of rays from the centroid to adjacent contour points.
double	computePlanarArea(Vector3d nrm, Point3d p0, boolean clockwiseContour) Computes the area of this contour projected onto a plane defined by a normal vector.
IntersectionContour	copy()
boolean	dividesMesh(PolygonalMesh mesh) Returns true if this contour divides the specified mesh into "inside" and "outside" regions.
int	findSegmentFaceStart(Face face, PolygonalMesh mesh) Returns an index at which the indicated face first appears as a segment face for the indicated mesh, or -1 if no such starting index is found, which means either that the segment face does not appear at all, or appears along the whole contour.
IntersectionPoint	firstFaceEntryPoint(PolygonalMesh mesh, Face face) Returns the point where the contour first enters the specified face on mesh.
IntersectionPoint	firstNonCoincidentPoint(double tol) Returns a point on the contour whose distance from the preceeding point is either null (for open contours), or whose distance from the preceeding point exceeds tol.
java.util.ArrayList<IntersectionPoint>	fitPlane(Vector3d areaVec, Vector3d centroid, double pointTol) Fits this contour to a plane by first computing the centroid, and then forming a normal by summing the cross products of adjacent rays between the centroid and the contour points.
java.util.ArrayList<IntersectionPoint>	getCornerPoints()
java.util.ArrayList<IntersectionPoint>	getCornerPoints(double tol) Return the subset of points that form the corners of this contour.
IntersectionPoint	getFirst() Returns the first point of this contour, or null if the contour is empty.
IntersectionPoint	getLast() Returns the last point of this contour, or null if the contour is empty.
IntersectionPoint	getNext(IntersectionPoint p) Returns the next intersection point after p on this contour.
IntersectionPoint	getPrev(IntersectionPoint p) Returns the previous intersection point after p on this contour.
IntersectionPoint	getWrapped(int idx) Get with wrapping implemented for closed contours.
int	getWrappedIndex(int idx) Takes an arbitrary index value for a contour point returns either its wrapped value (for closed contours), or checks its range and returns either the index itself or -1 if it is out of range (for open contours).
boolean	isClosed() Query if this contour is closed.
void	printCornerPoints(java.lang.String name, java.lang.String fmt, RigidTransform3d T)
void	reverse()

Methods inherited from class java.util.ArrayList

add, add, addAll, addAll, clear, clone, contains, ensureCapacity, forEach, get, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeIf, replaceAll, retainAll, set, size, sort, spliterator, subList, toArray, toArray, trimToSize

Methods inherited from class java.util.AbstractList

equals, hashCode

Methods inherited from class java.util.AbstractCollection

containsAll, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.List

containsAll, equals, hashCode

Methods inherited from interface java.util.Collection

parallelStream, stream

Field Detail

isClosed

public boolean isClosed

isContinuable

public boolean isContinuable

openMesh

public boolean openMesh

containingFace

public Face containingFace

singleFaceArea

public double singleFaceArea

Constructor Detail

IntersectionContour

public IntersectionContour()

Method Detail

isClosed

public boolean isClosed()

Query if this contour is closed.

Returns:

true if the contour is closed.

dividesMesh

public boolean dividesMesh(PolygonalMesh mesh)

Returns true if this contour divides the specified mesh into "inside" and "outside" regions. This will be true if

• the contour is closed;
• both end points of the contour lie on boundary edges of the mesh

Returns:

true if this contour divides the mesh

reverse

public void reverse()

getWrapped

public IntersectionPoint getWrapped(int idx)

Get with wrapping implemented for closed contours. If the contour is open and the index is out of bounds, null is returned.

Parameters:

idx - index of point to get

Returns:

point at index idx

getWrappedIndex

public int getWrappedIndex(int idx)

Takes an arbitrary index value for a contour point returns either its wrapped value (for closed contours), or checks its range and returns either the index itself or -1 if it is out of range (for open contours).

Parameters:

idx - index value to check

Returns:

wrapped value, or -1 is the contour is open and idx is out of range

computePlanarArea

public double computePlanarArea()

Computes the area of this contour with respect to a plane formed by computing the centroid and then summing the cross products of rays from the centroid to adjacent contour points.

Returns:

planar area

computeCentroid

public void computeCentroid(Vector3d centroid)

Computes the centroid of this contour, rejecting points that are very close together.

Parameters:

centroid - returns the centroid

computeLength

public double computeLength()

Computes the length of this contour

Returns:

contour length

computePlanarArea

public double computePlanarArea(Vector3d nrm,
                                Point3d p0,
                                boolean clockwiseContour)

Computes the area of this contour projected onto a plane defined by a normal vector. p0 provides a base point for area calculations.

getCornerPoints

public java.util.ArrayList<IntersectionPoint> getCornerPoints()

getCornerPoints

public java.util.ArrayList<IntersectionPoint> getCornerPoints(double tol)

Return the subset of points that form the corners of this contour.

printCornerPoints

public void printCornerPoints(java.lang.String name,
                              java.lang.String fmt,
                              RigidTransform3d T)

fitPlane

public java.util.ArrayList<IntersectionPoint> fitPlane(Vector3d areaVec,
                                                       Vector3d centroid,
                                                       double pointTol)

Fits this contour to a plane by first computing the centroid, and then forming a normal by summing the cross products of adjacent rays between the centroid and the contour points. This sum is returned in the optional argument areaVec.

When computing the centroid, points closer to each other than pointTol are ignored. The points that are actually used are collected into a separate list that is returned by this method.

Parameters:

areaVec - if non-null, returns the computed area vector. Normalizing this vector gives the normal for the plane, while the length of this vector gives twice the area of the contour with respect to the plane.

centroid - if non-null, returns the computed centroid.

pointTol - minimum distance between contour points used for computing the plane

Returns:

list of contours points with those closer than pointTol removed.

getFirst

public IntersectionPoint getFirst()

Returns the first point of this contour, or null if the contour is empty.

Returns:

first point of this contour, or null

getNext

public IntersectionPoint getNext(IntersectionPoint p)

Returns the next intersection point after p on this contour. If the contour is open and p is the last point, returns null.

getPrev

public IntersectionPoint getPrev(IntersectionPoint p)

Returns the previous intersection point after p on this contour. If the contour is open and p is the first point, returns null.

getLast

public IntersectionPoint getLast()

Returns the last point of this contour, or null if the contour is empty.

Returns:

last point of this contour, or null

findSegmentFaceStart

public int findSegmentFaceStart(Face face,
                                PolygonalMesh mesh)

Returns an index at which the indicated face first appears as a segment face for the indicated mesh, or -1 if no such starting index is found, which means either that the segment face does not appear at all, or appears along the whole contour.

firstFaceEntryPoint

public IntersectionPoint firstFaceEntryPoint(PolygonalMesh mesh,
                                             Face face)

Returns the point where the contour first enters the specified face on mesh. If the contour does not enter the face, or if it is entirely located on the face, the method returns -1.

If face is null, then the methods returns the first point where the contour first enters any face. For open contours, this is always the first point. If the contour is closed and entirely associated with one face, there is no entry index and the method returns null.

firstNonCoincidentPoint

public IntersectionPoint firstNonCoincidentPoint(double tol)

Returns a point on the contour whose distance from the preceeding point is either null (for open contours), or whose distance from the preceeding point exceeds tol. On closed contours, the latter is found by searching in reverse from the first point. If no such point is found (i.e., all points have a distance <= tol between them), null is returned.

copy

public IntersectionContour copy()