PolygonReduction Manual

Table of Contents

About

The PolygonReduction class allows to reduce the polygon count of a given PolygonObject while retaining its overall shape. The class gives access to the functionality used within the "Polygon Reduction" generator. It is defined in the lib_polygonreduction.h header file.

Allocation/Deallocation

A PolygonReduction object can be created with the usual tools, see Entity Creation and Destruction Manual (Cinema API).

  • PolygonReduction::Alloc(): Creates a new PolygonReduction object.
  • PolygonReduction::Free(): Deletes the given PolygonReduction object.

Init

A PolygonReduction object has to be initialized. It will pre-process the given PolygonObject.

  • PolygonReduction::PreProcess(): Pre-processes the PolygonObject defined in the given PolygonReductionData argument.

The PolygonReductionData argument has these members:

  • PolygonReductionData::_doc: The BaseDocument hosting the PolygonObject.
  • PolygonReductionData::_op: The target PolygonObject.
  • PolygonReductionData::_thread: The caller thread. If set to nullptr, the PolygonReduction object will pre-process the PolygonObject synchronously.
  • PolygonReductionData::_settings: A BaseContainer for further settings. See the parameter IDs in opolyreduxgen.h.
Note
In order to be able to abort the reduction operation and to retain the original mesh, it is advised to operate on a copy of the original PolygonObject.

If the PolygonReductionData::_thread member is set the pre-process is running asynchronously in a background thread.

  • PolygonReduction::IsPreprocessing(): Returns true if the pre-process is running.
  • PolygonReduction::StopPreprocessing(): Aborts preprocessing.
  • PolygonReduction::Reset(): Aborts preprocessing and frees all temporary data.
Note
This asynchronous mode may be used e.g. in a generator object.

After the pre-process the PolygonReduction object is ready:

  • PolygonReduction::IsValid(): Returns true if a valid object and a valid document are associated with the object.
  • PolygonReduction::GetData(): Returns the PolygonReductionData associated with the object.

Reduce

The linked PolygonObject can be reduced by defining the overall reduction strength or the target triangle, vertex or edge count.

  • PolygonReduction::GetMaxReductionStrengthLevel(): Returns the maximum reduction strength (1.0)
  • PolygonReduction::SetReductionStrengthLevel(): Sets the overall reduction strength.
  • PolygonReduction::GetReductionStrengthLevel(): Returns the current overall reduction strength.

The desired triangle count is defined with:

  • PolygonReduction::SetTriangleLevel(): Sets the desired triangle count.
Note
  • The desired triangle count must be between the Max and Min values retrieve with:
    • PolygonReduction::GetMaxTriangleLevel(): Returns the maximum number of triangles possible.
    • PolygonReduction::GetMinTriangleLevel(): Returns the minimum number of triangles possible.
  • The actual triangle count can be retrieve with:
    • PolygonReduction::GetTriangleLevel(): Returns the actual current triangle count.

The vertex count is defined with:

  • PolygonReduction::SetVertexLevel(): Sets the desired vertex count.
Note
  • The desired vertex count must be between the Max and Min values retrieve with:
    • PolygonReduction::GetMaxVertexLevel(): Returns the maximum number of vertices possible.
    • PolygonReduction::GetMinVertexLevel(): Returns the minimum number of vertices possible.
  • The actual vertex count can be retrieve with:
    • PolygonReduction::GetVertexLevel(): Returns the actual current vertex count.

Finally the edge count can be defined:

  • PolygonReduction::SetRemainingEdgesLevel(): Sets the desired edge count.
Note
  • The desired edge count must be less than the Max value retrieve with:
    • PolygonReduction::GetMaxRemainingEdgesLevel(): Returns the number of remaining edges.
  • The actual edge count can be retrieve with:
    • PolygonReduction::GetRemainingEdgesLevel(): Returns the actual edge count.

Further Reading