glPixelZoom
[New
- Windows 95, OEM Service Release 2]
The glPixelZoom
function specifies the pixel zoom factors.
void glPixelZoom(
|
GLfloat xfactor, |
|
|
GLfloat yfactor |
|
|
); |
|
Parameters
xfactor,
yfactor
The x
and y zoom factors for pixel write operations.
Remarks
The glPixelZoom
function specifies values for the x and y zoom factors. During
the execution of glDrawPixels
or glCopyPixels,
if (x (r) , y (r)
) is the current raster position, and
a given element is in the nth row and mth column of the pixel
rectangle, then pixels whose centers are in the rectangle with corners at
{bml bm53.BMP}
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.
The following
functions retrieve information related to glPixelZoom:
glGet
with argument GL_ZOOM_X
glGet with
argument GL_ZOOM_Y
Error Codes
The following
are the error codes generated and their conditions.
|
Error
Code |
Condition |
|
GL_INVALID_OPERATION
|
glPixelZoom was called between a call to glBegin and the
corresponding call to glEnd. |
See Also