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HLRBRep


HLRBRep_Algo Class Reference

A framework to compute a shape as seen in a projection plane. This is done by
calculating the visible and the hidden parts of the shape.
HLRBRep_Algo works with three types of entity:
- shapes to be visualized
- edges in these shapes (these edges are
the basic entities which will be visualized or hidden), and
- faces in these shapes which hide the edges.
HLRBRep_Algo is based on the principle of comparing each edge of the shape to be
visualized with each of its faces, and calculating the visible and the hidden parts of each edge.
For a given projection, HLRBRep_Algo calculates a set of lines characteristic of the
object being represented. It is also used in conjunction with the
HLRBRep_HLRToShape extraction utilities, which reconstruct a new, simplified shape
from a selection of calculation results. This new shape is made up of edges, which
represent the shape visualized in the projection.
HLRBRep_Algo takes the shape itself into account whereas HLRBRep_PolyAlgo
works with a polyhedral simplification of the shape. When you use HLRBRep_Algo, you
obtain an exact result, whereas, when you use HLRBRep_PolyAlgo, you reduce
computation time but obtain polygonal segments. In the case of complicated
shapes, HLRBRep_Algo may be time-consuming.
An HLRBRep_Algo object provides a framework for:
- defining the point of view
- identifying the shape or shapes to be visualized
- calculating the outlines
- calculating the visible and hidden lines of the shape.
Warning
- Superimposed lines are not eliminated by this algorithm.
- There must be no unfinished objects inside the shape you wish to visualize.
- Points are not treated.
- Note that this is not the sort of algorithm used in generating shading, which
calculates the visible and hidden parts of each face in a shape to be visualized by
comparing each face in the shape with every other face in the same shape.
.

#include <HLRBRep_Algo.hxx>

Inheritance diagram for HLRBRep_Algo:

Inheritance graph
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Public Member Functions

Standard_EXPORT HLRBRep_Algo ()
 Constructs an empty framework for the
calculation of visible and hidden lines of a shape in a projection.
Use the function:
- Projector to define the point of view
- Add to select the shape or shapes to be visualized
- Update to compute the outlines of the shape, and
- Hide to compute the visible and hidden lines of the shape.
.
Standard_EXPORT HLRBRep_Algo (const Handle(HLRBRep_Algo)&A)
Standard_EXPORT void Add (const TopoDS_Shape &S, const Handle(MMgt_TShared)&SData, const Standard_Integer nbIso=0)
 add the Shape <s>.

Standard_EXPORT void Add (const TopoDS_Shape &S, const Standard_Integer nbIso=0)
 Adds the shape S to this framework, and
specifies the number of isoparameters nbiso desired in visualizing S.
You may add as many shapes as you wish. Use the function Add once for each shape.
.
Standard_EXPORT Standard_Integer Index (const TopoDS_Shape &S)
 return the index of the Shape <s> and
return 0 if the Shape <s> is not found.

Standard_EXPORT void OutLinedShapeNullify ()
 nullify all the results of OutLiner from HLRTopoBRep.

Standard_EXPORT const Handle (Standard_Type)&DynamicType() const

Constructor & Destructor Documentation

Standard_EXPORT HLRBRep_Algo::HLRBRep_Algo  ) 
 

Standard_EXPORT HLRBRep_Algo::HLRBRep_Algo const Handle(HLRBRep_Algo)&  A  ) 
 


Member Function Documentation

Standard_EXPORT void HLRBRep_Algo::Add const TopoDS_Shape &  S,
const Standard_Integer  nbIso = 0
 

Standard_EXPORT void HLRBRep_Algo::Add const TopoDS_Shape &  S,
const Handle(MMgt_TShared)&  SData,
const Standard_Integer  nbIso = 0
 

Standard_EXPORT const HLRBRep_Algo::Handle Standard_Type   )  const
 

Reimplemented from HLRBRep_InternalAlgo.

Standard_EXPORT Standard_Integer HLRBRep_Algo::Index const TopoDS_Shape &  S  ) 
 

Standard_EXPORT void HLRBRep_Algo::OutLinedShapeNullify  ) 
 


The documentation for this class was generated from the following file:
Generated on Mon Aug 25 13:42:03 2008 for OpenCASCADE by  doxygen 1.4.1