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GLSCISSOR(3G)                                                                                  GLSCISSOR(3G)



NAME
       glScissor - define the scissor box


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


PARAMETERS
       x, y Specify the lower left corner of the scissor box.  Initially (0, 0).

       width, height
            Specify  the width and height of the scissor box.  When a GL context is first attached to a win-dow, window,
            dow, width and height are set to the dimensions of that window.

DESCRIPTION
       glScissor defines a rectangle, called the scissor box, in window coordinates.  The  first  two  argu-ments, arguments,
       ments,  x  and  y,  specify the lower left corner of the box.  width and height specify the width and
       height of the box.

       To enable and disable the scissor test, call glEnable and glDisable  with  argument  GL_SCISSOR_TEST.
       The  test  is initially disabled.  While the test is enabled, only pixels that lie within the scissor
       box can be modified by drawing commands.  Window coordinates have integer values at the  shared  cor-ners corners
       ners  of frame buffer pixels.  glScissor(0,0,1,1) allows modification of only the lower left pixel in
       the window, and glScissor(0,0,0,0) doesn't allow modification of any pixels in the window.

       When the scissor test is disabled, it is as though the scissor box includes the entire window.

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

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

ASSOCIATED GETS
       glGet with argument GL_SCISSOR_BOX
       glIsEnabled with argument GL_SCISSOR_TEST

SEE ALSO
       glEnable(3G), glViewport(3G)




                                                                                               GLSCISSOR(3G)