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Diffstat (limited to 'nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/frontface.gl')
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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/frontface.gl b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/frontface.gl new file mode 100644 index 000000000..ace895ad6 --- /dev/null +++ b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/frontface.gl @@ -0,0 +1,83 @@ +_C_ License Applicability. Except to the extent portions of this file are +_C_ made subject to an alternative license as permitted in the SGI Free +_C_ Software License B, Version 1.1 (the "License"), the contents of this +_C_ file are subject only to the provisions of the License. You may not use +_C_ this file except in compliance with the License. You may obtain a copy +_C_ of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 +_C_ Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: +_C_ +_C_ http://oss.sgi.com/projects/FreeB +_C_ +_C_ Note that, as provided in the License, the Software is distributed on an +_C_ "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS +_C_ DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND +_C_ CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A +_C_ PARTICULAR PURPOSE, AND NON-INFRINGEMENT. +_C_ +_C_ Original Code. The Original Code is: OpenGL Sample Implementation, +_C_ Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, +_C_ Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. +_C_ Copyright in any portions created by third parties is as indicated +_C_ elsewhere herein. All Rights Reserved. +_C_ +_C_ Additional Notice Provisions: The application programming interfaces +_C_ established by SGI in conjunction with the Original Code are The +_C_ OpenGL(R) Graphics System: A Specification (Version 1.2.1), released +_C_ April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version +_C_ 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X +_C_ Window System(R) (Version 1.3), released October 19, 1998. This software +_C_ was created using the OpenGL(R) version 1.2.1 Sample Implementation +_C_ published by SGI, but has not been independently verified as being +_C_ compliant with the OpenGL(R) version 1.2.1 Specification. +_C_ +_C_ The first character in this file must be an '_'! +_C_ Anything on a line after _C_ is ignored +_define(_filters,eqn)_C_ +_C_ eqn is automatically replaced with neqn for nroff +_header(FrontFace,define front- and back-facing polygons) +_names(FrontFace) +.EQ +delim $$ +.EN +.SH PARAMETERS +_phead(_param1) +Specifies the orientation of front-facing polygons. +_const(CW) and _const(CCW) are accepted. +The initial value is _const(CCW). +.SH 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 _cmnd(Enable) +and _cmnd(Disable) with argument _const(CULL_FACE). +.P +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. +_cmnd specifies whether polygons with clockwise winding in window coordinates, +or counterclockwise winding in window coordinates, +are taken to be front-facing. +Passing _const(CCW) to _param1 selects counterclockwise polygons as +front-facing; +_const(CW) selects clockwise polygons as front-facing. +By default, counterclockwise polygons are taken to be front-facing. +.SH ERRORS +_const(INVALID_ENUM) is generated if _param1 is not an accepted value. +.P +_const(INVALID_OPERATION) is generated if _cmnd +is executed between the execution of _cmnd(Begin) +and the corresponding execution of _cmnd(End). +.SH ASSOCIATED GETS +_cmnd(Get) with argument _const(FRONT_FACE) +.SH SEE ALSO +_cmnd(CullFace), +_cmnd(LightModel) |