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CSGBuilder

Creates Constructive Solid Geometry (CSG) from pairs of solid geometry features which are input through the A and B ports.

CSG is useful for representing complex solids by specifying the Boolean operations between simpler solids. For example, a wall with a window can be represented by taking the difference of the solid wall against the window. The CSGBuilder can be used to create a CSG solid that is comprised of relationships (order of Boolean operations or a hierarchy of Boolean operations) between the simpler solids.

Input Ports

  • A and B: Pairs of solid geometry features.

Output Ports

Each Boolean operator is output via its corresponding port:

ClosedUnion

Merges two objects into one.

ClosedDifference

Subtracts one object from another.

ClosedIntersection

The portion common to both objects.

Closed<Rejected>

Any features that do not have solid geometry, or extra features that come after the first feature with solid geometry in each group, are output through the <Rejected> port.

Parameters

ClosedGroup By

If any Group By attributes are given, then each group will be treated independently. This allows a single transformer to operate on multiple pairs of input features.

ClosedParallel Processing

Note: How parallel processing works with FME: see About Parallel Processing for detailed information.

This parameter determines whether or not the transformer should perform the work across parallel processes. If it is enabled, a process will be launched for each group specified by the Group By parameter.

Parallel Processing Levels

Parameter Number of Processes
No Parallelism 1
Minimal coresThe processor, or CPU, is the physical part of the computer that performs mathematical calculations. It is the most important part of a computer system. Traditional processors have only one core on the processor, meaning that at any given time, only one set of calculations is being performed. If a processor is dual-core, this means the single chip contains hardware for two processors, now called cores to distinguish them from the single chip, running simultaneously, side by side. (Source: http://www.ehow.com/facts_5730257_computer-core-processors_.html) / 2
Moderate exact number of cores
Aggressive cores x 1.5
Extreme cores x 2

For example, on a quad-core machine, minimal parallelism will result in two simultaneous FME processes. Extreme parallelism on an 8-core machine would result in 16 simultaneous processes.

You can experiment with this feature and view the information in the Windows Task Manager and the Workbench Log window.

ClosedInput Ordered

No: This is the default behavior. Processing will only occur in this transformer once all input is present.

By Group: This transformer will process input groups in order. Changes on the value of the Group By parameter on the input stream will trigger batch processing on the currently accumulating group. This will improve overall speed if groups are large/complex, but could cause undesired behavior if input groups are not truly ordered.

Related Transformers

CSG is the unevaluated model. The CSGEvaluator can be used to compute the equivalent boundary representation of the CSG solid.  

Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Transformer Categories

3D

Geometries

FME Licensing Level

FME Professional edition and above

Resources

See the definition of CSG at http://en.wikipedia.org/wiki/Constructive_solid_geometry.

 

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