Appearance
Appearance is a dual purpose attribute. It defines rendering attributes for 0-dim geometries (points, vertices and sets of them).
It is also the "base" for line style, which defines rendering attributes for 1-dim geometries (lines, curves, edges, wires and sets of them)
and material (surfaces, faces, etc.).
Appearance can be accessed via IAppearance_DG Interface returned by IEntity_DG.GetAppearance(). Use IAppearance_DG.GetDimension() to determine the actual type of the appearance:
Appearance of mixed dimension compounds
IAppearance_DG.GetDimension() consides with the dimension returned by IGeometry_DG.GetDimension() called for geometry of the entity. An exception is the case of a compound shape with mixed dimension sub-shapes in a "BRep" geometry type. In the later case IGeometry_DG.GetDimension() returns eUd (unknown) and appearances for each dimension are stored in properties of the entity.
To access per dimension appearances for a mixed dimension compound, query IPropertyArray from IEntity_DG and use IPropertyArray.GetProperty(Property_name), where Property_name is:
And query the interface specifies in the above table from the returned object. See also IBRepCompundTest.MixedDimsTest_Apearance() in Samples\NET\C#\Tests\InterfaceTests sample project installed with the product.
IEntity_DG.GetAppearance() returns one of the per dimension appearances in the case. Which one, depends on the history of the entity. Use IAppearance_DG.GetDimension() to determine the case.
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