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GLVIEWPORT()							  GLVIEWPORT()

NAME
       glViewport - set	the viewport

C SPECIFICATION
       void glViewport(	GLint x,
			GLint y,
			GLsizei	width,
			GLsizei	height )

       delim $$

PARAMETERS
       x, y Specify  the  lower	left corner of the viewport rectangle, in pix-
	    els. The initial value is (0,0).

       width, height
	    Specify the	width and height of the	viewport.  When	a  GL  context
	    is first attached to a window, width and height are	set to the di-
	    mensions of	that window.

DESCRIPTION
       glViewport specifies the	affine transformation of $x$ and $y$ from nor-
       malized	device coordinates to window coordinates.  Let ($x sub nd$, $y
       sub nd$)	be normalized device coordinates.  Then	the window coordinates
       ($x sub w$, $y sub w$) are computed as follows:

	 x sub w ~=~ ( x sub nd	+ 1 ) left ( "width" over 2 right ) ~+~	"x"

	 y sub w ~=~ ( y sub nd	+ 1 ) left ( "height" over 2 right ) ~+~ "y"

       Viewport	 width and height are silently clamped to a range that depends
       on the implementation.  To query	this range, call glGet	with  argument
       GL_MAX_VIEWPORT_DIMS.

ERRORS
       GL_INVALID_VALUE	is generated if	either width or	height is negative.

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

ASSOCIATED GETS
       glGet with argument GL_VIEWPORT
       glGet with argument GL_MAX_VIEWPORT_DIMS

SEE ALSO
       glDepthRange

								  GLVIEWPORT()

NAME | C SPECIFICATION | PARAMETERS | DESCRIPTION | ERRORS | ASSOCIATED GETS | SEE ALSO

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