MiGeometryHexahedronIjk Class Reference
[Geometry]

Generic geometry interface for hexahedron mesh Ijk. More...

#include <MeshVizXLM/mesh/geometry/MiGeometryHexahedronIjk.h>

Inheritance diagram for MiGeometryHexahedronIjk:

List of all members.

Public Member Functions
virtual void	getCellCoords (size_t i, size_t j, size_t k, MbVec3d &v0, MbVec3d &v1, MbVec3d &v2, MbVec3d &v3, MbVec3d &v4, MbVec3d &v5, MbVec3d &v6, MbVec3d &v7) const =0
virtual MiMeshIjk::StorageLayout	getStorageLayout () const

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Detailed Description

Generic geometry interface for hexahedron mesh Ijk.

Generic geometry interface representing a 3D grid of hexahedron cells, where each hexahedron is defined explicitly with 8 independent coordinates. Each hexahedron is accessible via 3 indices (i,j,k).

This type of geometry is typically used by the MiVolumeMeshVertexHexahedronIjk interface.

The vertices of each hexahedron are numbered as follows (see getCellCoords for more details):

                         J
                         |
                         |

                        n3----------n2
                        /|          /|
                      /  |        /  |
                    /    |      /    |
                  n7---------n6      |
                   |     |    |      |
                   |    n0----|-----n1    --- I
                   |    /     |     /
                   |  /       |   /
                   |/         | /
                  n4---------n5

                /
              /
            K
  

See related examples:

MyVolumeMeshVertexHexahedronIjk

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Member Function Documentation

virtual void MiGeometryHexahedronIjk::getCellCoords	(	size_t	i,
		size_t	j,
		size_t	k,
		MbVec3d &	v0,
		MbVec3d &	v1,
		MbVec3d &	v2,
		MbVec3d &	v3,
		MbVec3d &	v4,
		MbVec3d &	v5,
		MbVec3d &	v6,
		MbVec3d &	v7
	)			const [pure virtual]

Returns the coordinates of the hexahedron (i,j,k) cell.

The vertices of each hexahedron are numbered as follows :

• The first 4 vertices define the "bottom" face of the hexahedron. This face is on the logical IJ plane K=k.
• The last 4 vertices define the "top" face of the hexahedron. This face is on the logical IJ plane K=k+1.
  

  Vertices numbering

  Parameters:

  	i	[in] the id of this hexahedron on the axis I. 0 <= i < meshTopologyIjk.getNumCellsI().
  	j	[in] the id of this hexahedron on the axis J. 0 <= j < meshTopologyIjk.getNumCellsJ().
  	k	[in] the id of this hexahedron on the axis K. 0 <= k < meshTopologyIjk.getNumCellsK().
  	v0,v1,v2,v3,v4,v5,v6,v7	[out] the 8 vertices of the hexahedron (i,j,k).

virtual MiMeshIjk::StorageLayout MiGeometryHexahedronIjk::getStorageLayout

(

)

const [inline, virtual]

Hint about hexahedron organization in memory.

This information aims at optimizing the geometry traversal for extractors. Returns the geometry internal hexahedron layout in memory as 6 enum values covering all possible cases.

For example, LAYOUT_KJI means that:

• the hexahedron (i+1,j,k) is consecutive in memory to the hexahedron (i,j,k) and,
• the row of hexahedron (j+1,k) is consecutive in memory to the row of hexahedron (j,k) and,
• the slice of hexahedron (k+1) is consecutive in memory to the slice of hexahedron (k)

The fastest way to go through a hexahedron mesh with LAYOUT_KJI should be to perform the following triple loop:

    for each k with 0 <= k < numK
     for each j with 0 <= j < numJ
       for each i with 0 <= i < numI
         geometry.getCellCoords(i,j,k,n0, ... ,n7);
    

The default implementation returns LAYOUT_UNKNOWN meaning that the hexahedron storage organization is unknown, for instance when hexahedron are computed on the fly. In that case, extractors perform the hexahedron traversal in the way that minimizes the required memory for their algorithms.

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

• MeshVizXLM/mesh/geometry/MiGeometryHexahedronIjk.h