Module category: Tools

• MakeOctTree
  • Parameters
  • Input Ports
  • Output Ports
  • Examples

MakeOctTree

MakeOctTree generates octrees for unstructured grids and polygons. An object of class OctTree is generated for unstructured grids, whereis for Polygons a OctTreeP object is generated. In general you will never use this module except in 2 situations: when you are using more than one tracer module for the same data set, and when you want to change the default values which control octree construction.

It's available in version 5.2.2.

Parameters

Name	Type	Description
normal_size	scalar	The bounding box of the geometric domain is uniformly divided into several octrees (subdomains). The number of octrees is influenced by this parameter. Its meaning is as follows: if the grid were uniform, then the number of cells in each subdomain would be with good approximation the value of this parameter, as long as the total number of cells is of course high enough.
max_no_levels	scalar	The maximum number of levels in an octree.
min_small_enough	scalar	When an octree leaf contains less than some number of elements, leaf division is interrupted. This number is in general greater than the value of this parameter, but you may influence it through this parameter.
crit_level	scalar	From this level leaf division is interrupted if a would-be son-cell contains as many cells as the parent.
limit_fX	scalar	This parameter influences how the bounding box of the geometric object is subdivided into a number of subdomains for as many octrees. In particular this parameter limits the number of division in the X-dimension.
limit_fY	scalar	See comment for limit_fX. This parameter limits the number of division in the Y-dimension.
limit_fZ	scalar	See comment for limit_fX. This parameter limits the number of division in the Z-dimension.

Input Ports

Name	Type	Description
requiredinGrid	UnstructuredGrid Polygons	Input grid

Output Ports

Name	Type	Description
outputoutOctTree	OctTree OctTreeP	Output octree

Examples

This example illustrates how the use of this module may optimise an anlysis with two Tracer modules. The same pipeline might also be used without MakeOctTreeMap and the results would be the same.

Figure: covise/net/examples/MakeOctTree.net