glPixelZoom(3)

NAME

       glPixelZoom - specify the pixel zoom factors

C SPECIFICATION

       void glPixelZoom( GLfloat xfactor,
                         GLfloat yfactor )

       delim $$

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  $m$th  row  and
       $n$th  column  of the pixel rectangle, then pixels whose centers are in
       the rectangle with corners at

               ($xr ~+~ n cdot "xfactor"$, $yr ~+~ m cdot "yfactor"$)

           ($xr ~+~ (n+1) cdot "xfactor"$, $yr ~+~ (m+1) cdot "yfactor"$)

       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(3G), glDrawPixels(3G)

                                                               GLPIXELZOOM(3G)