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GLFRONTFACE(3G)                                  OpenGL 3.3                                  GLFRONTFACE(3G)



NAME
       glFrontFace - define front- and back-facing polygons

C SPECIFICATION
       void glFrontFace(GLenum mode);

PARAMETERS
       mode
           Specifies the orientation of front-facing polygons.  GL_CW and GL_CCW are accepted. The initial
           value is GL_CCW.

DESCRIPTION
       In a scene composed entirely of opaque closed surfaces, back-facing polygons are never visible.
       Eliminating these invisible polygons has the obvious benefit of speeding up the rendering of the
       image. To enable and disable elimination of back-facing polygons, call glEnable() and glDisable()
       with argument GL_CULL_FACE.

       The projection of a polygon to window coordinates is said to have clockwise winding if an imaginary
       object following the path from its first vertex, its second vertex, and so on, to its last vertex,
       and finally back to its first vertex, moves in a clockwise direction about the interior of the
       polygon. The polygon's winding is said to be counterclockwise if the imaginary object following the
       same path moves in a counterclockwise direction about the interior of the polygon.  glFrontFace
       specifies whether polygons with clockwise winding in window coordinates, or counterclockwise winding
       in window coordinates, are taken to be front-facing. Passing GL_CCW to mode selects counterclockwise
       polygons as front-facing; GL_CW selects clockwise polygons as front-facing. By default,
       counterclockwise polygons are taken to be front-facing.

ERRORS
       GL_INVALID_ENUM is generated if mode is not an accepted value.

ASSOCIATED GETS
       glGet() with argument GL_FRONT_FACE

SEE ALSO
       glCullFace(),


COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software
       B License. For details, see http://oss.sgi.com/projects/FreeB/.



OpenGL 3.3                                       03/08/2011                                  GLFRONTFACE(3G)