Index for Section 3G

Alphabetical listing for G

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glPixelZoom(3G)
NAME
  glPixelZoom - specify the pixel zoom factors

SYNOPSIS
  void glPixelZoom(
	  GLfloat xfactor,
	  GLfloat yfactor );

PARAMETERS
  xfactor, yfactor
      Specify the x and y zoom factors for pixel write operations.

DESCRIPTION
  glPixelZoom() specifies values for the x and y zoom factors. During the
  execution of glDrawPixels() or glCopyPixels(), if (xr , yr ) is the current
  raster position, and a given element is in the mth row and nth column of
  the pixel rectangle, then pixels whose centers are in the rectangle with
  corners at

       (xr + n cdot xfactor, yr + m . yfactor)
       (xr + (n+1) . xfactor, yr + (m+1) cdot yfactor)

  are candidates for replacement. Any pixel whose center lies on the bottom
  or left edge of this rectangular region is also modified.

  Pixel zoom factors are not limited to positive values. Negative zoom
  factors reflect the resulting image about the current raster position.

ERRORS
  GL_INVALID_OPERATION is generated if glPixelZoom() is executed between the
  execution of glBegin() and the corresponding execution of glEnd().

ASSOCIATED GETS
       glGet() with argument GL_ZOOM_X
       glGet() with argument GL_ZOOM_Y

SEE ALSO
  glCopyPixels(3) ,glDrawPixels(3)

Index for Section 3G

Alphabetical listing for G

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