Index for Section 3G

Alphabetical listing for G

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glViewport(3G)
NAME
  glViewport - set the viewport

SYNOPSIS
  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[n]d, y[n]d) 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.

  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(3)

Index for Section 3G

Alphabetical listing for G

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