NAME
gluBeginPolygon, gluEndPolygon
- delimit a polygon description
C SPECIFICATION
void gglluuBBeeggiinnPPoollyyggoonn(
GLUtesselator* _t_e_s_s )
void gglluuEEnnddPPoollyyggoonn(
GLUtesselator* _t_e_s_s )
delim $$
PARAMETERS
-
_t_e_s_s
-
Specifies the tessellation object (created with gglluuNNeewwTTeessss).
DESCRIPTION
gglluuBBeeggiinnPPoollyyggoonn and gglluuEEnnddPPoollyyggoonn delimit the definition of a
nonconvex polygon.
To define such a polygon, first call gglluuBBeeggiinnPPoollyyggoonn.
Then define the contours of the polygon
by calling
gglluuTTeessssVVeerrtteexx for each vertex
and gglluuNNeexxttCCoonnttoouurr to start each new contour.
Finally, call gglluuEEnnddPPoollyyggoonn
to signal the end of the definition.
See the gglluuTTeessssVVeerrtteexx and
gglluuNNeexxttCCoonnttoouurr reference pages for more details.
Once gglluuEEnnddPPoollyyggoonn is called, the polygon is tessellated, and the
resulting triangles are described through callbacks.
See gglluuTTeessssCCaallllbbaacckk for descriptions of the callback functions.
NOTES
This command is obsolete and is provided for backward compatibility
only. Calls to gglluuBBeeggiinnPPoollyyggoonn are mapped to
gglluuTTeessssBBeeggiinnPPoollyyggoonn
followed by
gglluuTTeessssBBeeggiinnCCoonnttoouurr. Calls to gglluuEEnnddPPoollyyggoonn are mapped
to gglluuTTeessssEEnnddCCoonnttoouurr followed by gglluuTTeessssEEnnddPPoollyyggoonn.
EXAMPLE
A quadrilateral with a triangular hole in it can be described like this:
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);
SEE ALSO
gglluuNNeewwTTeessss((33GG)), gglluuNNeexxttCCoonnttoouurr((33GG)), gglluuTTeessssCCaallllbbaacckk((33GG)), gglluuTTeessssVVeerrtteexx((33GG)),
gglluuTTeessssBBeeggiinnPPoollyyggoonn((33GG)), gglluuTTeessssBBeeggiinnCCoonnttoouurr((33GG))