GLDEPTHFUNC(3G)                 [FIXME: manual]                GLDEPTHFUNC(3G)

NAME
       glDepthFunc - specify the value used for depth buffer comparisons

C SPECIFICATION
       void glDepthFunc(GLenum func);

PARAMETERS
       func
           Specifies the depth comparison function. Symbolic constants
           GL_NEVER, GL_LESS, GL_EQUAL, GL_LEQUAL, GL_GREATER, GL_NOTEQUAL,
           GL_GEQUAL, and GL_ALWAYS are accepted. The initial value is
           GL_LESS.

DESCRIPTION
       glDepthFunc specifies the function used to compare each incoming pixel
       depth value with the depth value present in the depth buffer. The
       comparison is performed only if depth testing is enabled. (See
       glEnable() and

       glDisable of GL_DEPTH_TEST.)

       func specifies the conditions under which the pixel will be drawn. The
       comparison functions are as follows:

       GL_NEVER
           Never passes.

       GL_LESS
           Passes if the incoming depth value is less than the stored depth
           value.

       GL_EQUAL
           Passes if the incoming depth value is equal to the stored depth
           value.

       GL_LEQUAL
           Passes if the incoming depth value is less than or equal to the
           stored depth value.

       GL_GREATER
           Passes if the incoming depth value is greater than the stored depth
           value.

       GL_NOTEQUAL
           Passes if the incoming depth value is not equal to the stored depth
           value.

       GL_GEQUAL
           Passes if the incoming depth value is greater than or equal to the
           stored depth value.

       GL_ALWAYS
           Always passes.

       The initial value of func is GL_LESS. Initially, depth testing is
       disabled. If depth testing is disabled or if no depth buffer exists, it
       is as if the depth test always passes.

NOTES
       Even if the depth buffer exists and the depth mask is non-zero, the
       depth buffer is not updated if the depth test is disabled. In order to
       unconditionally write to the depth buffer, the depth test should be
       enabled and set to GL_ALWAYS.

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

ASSOCIATED GETS
       glGet() with argument GL_DEPTH_FUNC

       glIsEnabled() with argument GL_DEPTH_TEST

VERSION SUPPORT

       +------------+-----------------------------------------------------------------------+
       |            |                            OpenGL Version                             |
       +------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |Function /  | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5 |
       |Feature     |     |     |     |     |     |     |     |     |     |     |     |     |
       |Name        |     |     |     |     |     |     |     |     |     |     |     |     |
       +------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |glDepthFunc | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> |
       +------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

SEE ALSO
       glDepthRange(), glEnable(), glPolygonOffset()

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. Copyright (C) 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
       Copyright (C) 1991-2006 Silicon Graphics, Inc.
       Copyright (C) 2010-2014 Khronos Group

[FIXME: source]                   05/21/2022                   GLDEPTHFUNC(3G)