Index for Section 3G

Alphabetical listing for G

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glDepthFunc(3G)
NAME
  glDepthFunc - specify the value used for depth buffer comparisons

SYNOPSIS
  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.
  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.

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(3)(), glEnable(3), glPolygonOffset(3)

Index for Section 3G

Alphabetical listing for G

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