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Io-language-graphics-and-sound-20080330-6.fc15.i686.rpm

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     <STRONG>NAME</STRONG>
	  <STRONG>glDepthRange</STRONG> - specify mapping of depth values from
	  normalized device coordinates	to window coordinates


     <STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
	  void <STRONG>glDepthRange</STRONG>( GLclampd <EM>zNear</EM>,
			     GLclampd <EM>zFar</EM> )


     <STRONG>PARAMETERS</STRONG>
	  <EM>zNear</EM>	 Specifies the mapping of the near clipping plane to
		 window	coordinates.  The initial value	is 0.

	  <EM>zFar</EM>	 Specifies the mapping of the far clipping plane to
		 window	coordinates.  The initial value	is 1.

     <STRONG>DESCRIPTION</STRONG>
	  After	clipping and division by <EM>w</EM>, depth coordinates range
	  from -1 to 1,	corresponding to the near and far clipping
	  planes.  <STRONG>glDepthRange</STRONG>	specifies a linear mapping of the
	  normalized depth coordinates in this range to	window depth
	  coordinates.	Regardless of the actual depth buffer
	  implementation, window coordinate depth values are treated
	  as though they range from 0 through 1	(like color
	  components).	Thus, the values accepted by <STRONG>glDepthRange</STRONG> are
	  both clamped to this range before they are accepted.

	  The setting of (0,1) maps the	near plane to 0	and the	far
	  plane	to 1.  With this mapping, the depth buffer range is
	  fully	utilized.

     <STRONG>NOTES</STRONG>
	  It is	not necessary that <EM>zNear</EM> be less than <EM>zFar</EM>.  Reverse
	  mappings such	as zNear=1, and	zFar=0 are acceptable.

     <STRONG>ERRORS</STRONG>
	  <STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glDepthRange</STRONG> is
	  executed between the execution of <STRONG>glBegin</STRONG> and	the
	  corresponding	execution of <STRONG>glEnd</STRONG>.

     <STRONG>ASSOCIATED</STRONG>	<STRONG>GETS</STRONG>
	  <STRONG>glGet</STRONG>	with argument <STRONG>GL_DEPTH_RANGE</STRONG>

     <STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
	  <STRONG>glDepthFunc</STRONG>, <STRONG>glPolygonOffset</STRONG>,	<STRONG>glViewport</STRONG>






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