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GLVIEWPORT(3G)                                   OpenGL 3.3                                   GLVIEWPORT(3G)



NAME
       glViewport - set the viewport

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

PARAMETERS
       x, y
           Specify the lower left corner of the viewport rectangle, in pixels. 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 dimensions of that window.

DESCRIPTION
       glViewport specifies the affine transformation of x and y from normalized device coordinates to
       window coordinates. Let x nd y nd be normalized device coordinates. Then the window coordinates x w y
       w are computed as follows:


       x w = x nd + 1 ^/ width 2 + x


       y w = y nd + 1 ^/ height 2 + 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.

ASSOCIATED GETS
       glGet() with argument GL_VIEWPORT


       glGet() with argument GL_MAX_VIEWPORT_DIMS

SEE ALSO
       glDepthRange()


COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software
       B License. For details, see http://oss.sgi.com/projects/FreeB/.



OpenGL 3.3                                       03/08/2011                                   GLVIEWPORT(3G)