bionic (3) glFrontFace.3G.gz

Provided by: opengl-4-man-doc_1.0~svn33624-1_all bug

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

VERSION SUPPORT

       ┌────────────┬───────────────────────────────────────────────────────────────────────┐
       │            │                OpenGL Version                                         │
       ├────────────┼─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┤
       │Function2.02.13.03.13.23.34.04.14.24.34.44.5 │
       │/           │     │     │     │     │     │     │     │     │     │     │     │     │
       │Feature     │     │     │     │     │     │     │     │     │     │     │     │     │
       │Name        │     │     │     │     │     │     │     │     │     │     │     │     │
       ├────────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │glFrontFace │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
       └────────────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┘

SEE ALSO

       glCullFace(),

       Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2014 Khronos Group. This document is
       licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.

       Copyright © 1991-2006 Silicon Graphics, Inc.
       Copyright © 2010-2014 Khronos Group

[FIXME: source]                                    01/03/2018                                    GLFRONTFACE(3G)