Index for Section 3G

Alphabetical listing for G

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glScissor(3G)
NAME
  glScissor - define the scissor box

SYNOPSIS
  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 window, 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 arguments, 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 corners 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(), glViewport()

Index for Section 3G

Alphabetical listing for G

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