Specifies a vertex on a polygon.
OpenGL C bindings library: libGL.a
void gluTessVertex(GLUtriangulator Obj *tobj, GLdouble Vertex, void *Data)
The gluTessVertex subroutine describes a vertex on a polygon that the user is defining. Successive gluTessVertex calls describe a closed contour. For example, to describe a quadrilateral, the gluTessVertex subroutine must be called four times.
This subroutine can only be called between gluBeginPolygon and gluEndPolygon.
The Data parameter normally points to a structure containing the vertex location, as well as other vertex-specific attributes (such as color and normal). This pointer is passed back to the user through the GLU_VERTEX callback after tessellation. (See the gluTessCallback subroutine for details on defining callbacks for a tessellation object.)
|tobj||Specifies the tessellation object created with the gluNewTess subroutine.|
|Vertex||Specifies the location of the vertex.|
|Data||Specifies an opaque pointer that is passed back to the user with the vertex callback (as specified by the gluTessCallback subroutine).|
|/usr/include/GL/gl.h||Contains C language constraints, variable type definitions, and ANSI function prototypes for OpenGL.|
A quadrilateral with a triangle hole in it can be described as follows:
gluBeginPolygon(tobj); gluTessVertex(tobj, v1, v1); gluTessVertex(tobj, v2, v2); gluTessVertex(tobj, v3, v3); gluTessVertex(tobj, v4, v4); gluNextContour(tobj, GLU_INTERIOR); gluTessVertex(tobj, v5, v5); gluTessVertex(tobj, v6, v6); gluTessVertex(tobj, v7, v7); gluEndPolygon(tobj);
The gluBeginPolygon subroutine, gluNewTess subroutine, gluNextContour subroutine, gluTessCallback subroutine.