NAME    [Toc]    [Back]

       glPixelZoom - specify the pixel zoom factors

SYNOPSIS    [Toc]    [Back]

       void glPixelZoom(
               GLfloat xfactor,
               GLfloat yfactor );

PARAMETERS    [Toc]    [Back]

       Specify  the  x  and y zoom factors for pixel write operations.

DESCRIPTION    [Toc]    [Back]

       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    [Toc]    [Back]

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

ASSOCIATED GETS    [Toc]    [Back]

       glGet() with argument GL_ZOOM_X
       glGet() with argument GL_ZOOM_Y

SEE ALSO    [Toc]    [Back]

       glCopyPixels(3) ,glDrawPixels(3)



                                                  glPixelZoom(3G)