Boundable (Artisynth API documentation)

All Known Implementing Classes:

BSpline3dElement, Face, Feature, FemElement, FemElement3d, FemElement3dBase, FemNode3d, HalfEdge, HexElement, LineSegment, MFreeElement3d, MFreeModel3d.MFreeRestNode3d, MFreeNode3d, PyramidElement, QuadhexElement, QuadpyramidElement, QuadtetElement, QuadwedgeElement, ShellElement3d, ShellQuadElement, ShellTriElement, SubdivisionVertex3d, TetElement, Vertex3d, WedgeElement
```
public interface Boundable
```
Methods to be implemented by geometric elements that can be enclosed within a bounding volume tree.

Author:

lloyd

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`void`	`computeCentroid(Vector3d centroid)` Computed the centroid of this element.
`double`	`computeCovariance(Matrix3d C)` Computes the covariance of the element, assuming a uniform density of one.
`Point3d`	`getPoint(int idx)` Returns the `idx`-th point associated with this element.
`int`	`numPoints()` Returns the number of points associated with this element, if any, or zero otherwise.
`void`	`updateBounds(Vector3d min, Vector3d max)` Updates the axis-aligned bounds of this element.

- Method Detail
  - numPoints
```
int numPoints()
```
    Returns the number of points associated with this element, if any, or zero otherwise. If the element has points, then it's spatial extent is assumed to be enclosed within their convex hull. At present, elements that do not have points cannot be enclosed within oriented bounding box (OBB) trees.
    
    Returns:
    
    number of points associated with this element
  - getPoint
```
Point3d getPoint(int idx)
```
    Returns the idx-th point associated with this element.
    
    Parameters:
    
    idx - index of the point (must be on the range 0 to numPoints()).
    
    Returns:
    
    idx-th point associated with this element. Must not be modified.
  - computeCentroid
```
void computeCentroid(Vector3d centroid)
```
    Computed the centroid of this element.
    
    Parameters:
    
    centroid - returns the computed centroid value.
  - updateBounds
```
void updateBounds(Vector3d min,
                  Vector3d max)
```
    Updates the axis-aligned bounds of this element. The value in min and max should be decreased or increased, respectively, so that all spatial points associated with this element lie within the axis-aligned box defined by min and max.
    
    Parameters:
    
    min - minimum values to be updated
    
    max - maximum values to be updated
  - computeCovariance
```
double computeCovariance(Matrix3d C)
```
    Computes the covariance of the element, assuming a uniform density of one. The covariance is defined as
```
 int_V \rho x x^T dV,
 
```
    where \rho is the density, x is any spatial point within the element, and the integral is evaluated over the element's spatial extent. The method returns the element's spatial size, which for elements of dimension 3, 2, 1, or 0 will be a volume, area, length, or discrete value.
    Implementation of this method is optional, with non-implementation indicated by having the method return -1. Non-implementation may prevent the element from being enclosed within certain types of oriented bounding box (OBB) constructions.
    Parameters:
    
    C - returns the covariance
    
    Returns:
    
    spatial size of the element, or -1 if this method is not implemented.

Interface Boundable

Method Summary

Method Detail

numPoints

getPoint

computeCentroid

updateBounds

computeCovariance