OpenGL man pages
gluTessVertex.3gl (GLU version 1.2 and later)
gluTessVertex - specify a vertex on a polygon
void gluTessVertex( GLUtesselator *tess,
void *data )
tess Specifies the tessellation object (created with gluNewTess).
coords Specifies the location of the vertex.
data Specifies an opaque pointer passed back to the user with the vertex
callback (as specified by gluTessCallback).
gluTessVertex describes a vertex on a polygon that the user is defining.
Successive gluTessVertex calls describe a closed contour. For example, if
the user wants to describe a quadrilateral, then gluTessVertex should be
called four times. gluTessVertex can only be called between
gluTessBeginContour and gluTessEndContour.
data normally points to a structure containing the vertex location, as well
as other per-vertex attributes such as color and normal. This pointer is
passed back to the user through the GLU_TESS_VERTEX or GLU_TESS_VERTEX_DATA
callback after tessellation (see the gluTessCallback reference page).
A quadrilateral with a triangular hole in it can be described as follows:
gluTessVertex(tobj, v1, v1);
gluTessVertex(tobj, v2, v2);
gluTessVertex(tobj, v3, v3);
gluTessVertex(tobj, v4, v4);
gluTessVertex(tobj, v5, v5);
gluTessVertex(tobj, v6, v6);
gluTessVertex(tobj, v7, v7);
gluTessBeginPolygon, gluNewTess, gluTessBeginContour, gluTessCallback,
gluTessProperty, gluTessNormal, gluTessEndPolygon
Fri Dec 6 11:18:03 EST 1996
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