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BRep Surfaces

BRep Surfaces are used to define geometry of BRep faces. A BRep Surface can be thought of as a mapping of a rectangle in u,v plane into 3D space. Quite often the equations allow extending of definition of the surface outside of the rectangle.

Programmatically general attributes of a BRep surface are represented by IUVSurface_DG interface.

Parameter range for BSpline Surfaces can be accessed via IUVSurface_DG.GetParameterRange()

Surfaces can be closed in one (cylinder) or both (torus) directions. See IUVSurface_DG.IsClosed()

Surfaces can be infinite in one (cylinder) or both (plane) directions. A surface is infinite in u direction if its u range, as returned by IUVSurface_DG.GetParameterRange() is infinite (greater than 1.0E+307).

Specific types of surfaces supported in this release are:

Surface Type Interface to query
eSurfTypeBSpline IBSplineSurface_DG
eSurfTypeBezier IBezierSurface_DG
eSurfTypePlane IPlane_DG
eSurfTypeCone ICone_DG
eSurfTypeSphere ISphere_DG
eSurfTypeTorus ITorus_DG
eSurfTypeSurfaceOfRevolution ISurfaceOfRevolution_DG

The surface types here are enumerated by ESurfaceType_DG

The actual type of a surface can be determined using  IUVSurface_DG.GetSurfaceType() method.

Surfaces listed in the above table can be created new using call
IObjectGenerator_DG.Create("IBSplineSurface_DG") as IBSplineSurface_DG;
or similar.