glDepthFunc(3G)		       OpenGL Reference		       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 default value is
	   GL_LESS.


DESCRIPTION
     glDepthFunc specifies the function	used to	compare	each incoming pixel z
     value with	the z 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	z value	is less	than the
			 stored	z value.

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

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

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

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

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

     GL_ALWAYS		 Always	passes.

     The default value of func is GL_LESS.  Initially, depth testing is
     disabled.







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glDepthFunc(3G)		       OpenGL Reference		       glDepthFunc(3G)



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

     GL_INVALID_OPERATION is generated if glDepthFunc is executed between the
     execution of glBegin and the corresponding	execution of glEnd.

ASSOCIATED GETS
     glGet with	argument GL_DEPTH_FUNC
     glIsEnabled with argument GL_DEPTH_TEST


SEE ALSO
     glDepthRange, glEnable










































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