GLPIXELZOOM(3G) GLPIXELZOOM(3G)
NAME
glPixelZoom - specify the pixel zoom factors
C SPECIFICATION
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 * xfactor, yr + m * yfactor)
( xr + (n+1) * xfactor, yr + (m+1)*yfactor)
are candidates for replacement. Any pixel whose center lies on the bottom or left edge of this rect-angular rectangular
angular 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)
|