NAME
vtkLinearExtrusionFilter - sweep polygonal data creating a "skirt" from free edges and lines, and lines from vertices
SYNOPSIS
#include "/opt/vtk-c++/graphics/vtkLinearExtrusionFilter.h"
class VTK_EXPORT vtkLinearExtrusionFilter : public vtkPolyDataToPolyDataFilter
vtkLinearExtrusionFilter();
static vtkLinearExtrusionFilter *New() {return new vtkLinearExtrusionFilter;};
const char *GetClassName() {return "vtkLinearExtrusionFilter";};
void PrintSelf(ostream& os, vtkIndent indent);
void SetExtrusionType(int);
int GetExtrusionType();
void SetCapping(int);
int GetCapping();
void CappingOn();
void CappingOff();
void SetScaleFactor(float);
float GetScaleFactor();
void SetVector(float, float, float);
void SetVector(float *);
float *GetVector();
void GetVector(float data[3]);
void SetExtrusionPoint(float, float, float);
void SetExtrusionPoint(float *);
float *GetExtrusionPoint();
void GetExtrusionPoint(float data[3]);
DESCRIPTION
vtkLinearExtrusionFilter is a modelling filter. It takes polygonal data as input and generates polygonal data on output. The input dataset is swept according to some extrusion function and creates new polygonal primitives. These primitives form a "skirt" or swept surface. For example, sweeping a line results in a quadrilateral, and sweeping a triangle creates a "wedge".
There are a number of control parameters for this filter. You can control whether the sweep of a 2D object (i.e., polygon or triangle strip) is capped with the generating geometry via the "Capping" ivar. Also, you can extrude in the direction of a user specified vector, towards a point, or in the direction of vertex normals (normals must be provided - use vtkPolyDataNormals if necessary). The amount of extrusion is controlled by the "ScaleFactor" instance variable.
The skirt is generated by locating certain topological features. Free edges (edges of polygons or triangle strips only used by one polygon or triangle strips) generate surfaces. This is true also of lines or polylines. Vertices generate lines.
This filter can be used to create 3D fonts, 3D irregular bar charts, or to model 2 1/2D objects like punched plates. It also can be used to create solid objects from 2D polygonal meshes.
CAVEATS
Some polygonal objects have no free edges (e.g., sphere). When swept, this will result in two separate surfaces if capping is on, or no surface if capping is off.
SEE ALSO
vtkRotationalExtrusionFilter
DEFINED MACROS
VTK_VECTOR_EXTRUSION 1
VTK_NORMAL_EXTRUSION 2
VTK_POINT_EXTRUSION 3
SUMMARY
void SetExtrusionType(int)
Set/Get the type of extrusion.
void SetCapping(int)
Turn on/off the capping of the skirt.
void SetScaleFactor(float)
Set/Get extrusion scale factor,
void SetVector(float, float, float)
void SetVector(float *)
Set/Get extrusion vector. Only needs to be set if VectorExtrusion is turned on.
void SetExtrusionPoint(float, float, float)
void SetExtrusionPoint(float *)
Set/Get extrusion point. Only needs to be set if PointExtrusion is turned on. This is the point towards
which extrusion occurs.
vtkLinearExtrusionFilter()
Create object with normal extrusion type, capping on, scale factor=1.0, vector (0,0,1), and extrusion point (0,0,0).