Decimate Wireframe

Control for reducing the quantity of data in a wireframe model

Decimate Wireframe

To access this dialog:

  • Activate the Structure ribbon and select Operations | Decimate

The Decimate Wireframe dialog is used to select a wireframe object, define decimation parameters, reduce amount of data in a wireframe by reducing the number of edge and wireframe faces.

Read some decimation guidelines here...

Field Details:

Wireframe Name: displays the name ofthe wireframe object to be decimated. Note that you can use the Pick button to interactively select a wireframe object in the Design window (note that, due to the nature of the decimation command, only entire objects can be selected - you cannot perform a decimation on part of a wireframe).

Face Count: displays the number of faces in the selected wireframe.

Decimation Method: select either the faster, Quadratic Decimation (default), and the more accurate, Measured Decimation method.

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The Quadratic method is adequate in most circumstances.

 

Reduction Targets: enable the extent of the decimation process to be controlled.

  • Reduce By: % simplifies the wireframe until the requested percentage reduction has been achieved.  The precise reduction may not exactly match the requested amount.

  • Maximum Error: tick the box to apply a maximum error limit for the decimation algorithm; the reduction will continue until the removal of candidate vertices would produce a greater error than that specified (in world data units). It is a tolerance which limits the distance by which a face can move when a point is deleted.

For wireframes where dimensions are relatively small, like an underground mine design, use a very small tolerance.

 

Feature Preservation Weighting: defines what constitutes a feature and defines how important different features are.

  • Feature Edge Weight: enter a feature preserve weighting value for features defined by the corresponding (following) Feature Edge angle setting. Feature Edge Angle).

    This facility could be used to preserve bench boundaries, for example.

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A weighting of 0.0 will attach no importance to that feature and it will probably be lost; a value of 1.0 will try to preserve the feature; a weighting value of ; increasing the number means that those edges become increasingly less preferable for removable by the decimation algorithm. Choosing a large number e.g. 99999, should ensure that these edges are preserved (but may slow down processing, or prevent the algorithm from reaching its target reduction).

  • Feature Edge: the angle defining what are to be classed as feature -iIt has a sharper angle than the specified Feature Edge angle.

  • Boundary Edge Weight: controls the preservation of open edges. Weighting values operate in the same way as described in the notes above.

Output: select either In-Place i.e update the selected object (performing an 'in place' update) or New Object (default) i.e. create a new object to store the decimated data set.

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  • If the New Object option is selected, a new object using the naming format Decimated: Wireframe Name is created, where Wireframe Name is the name of the wireframe object selected for decimation.

  • In-place updating cannot be undone.