GDGetScale returns the current scale of the given screen graphics device.
pascal OSErr GDGetScale(GDHandle gdh,Fixed *scale,short *flags)
gdh A handle to a screen graphics device.
scale Pointer to a fixed point field to hold the scale result.
flags Pointer to a short integer. It returns the status parameter flags for the video driver. For now, 0 is always returned in this field.
Errors:
cDevErr Not a screen device.
controlErr Video driver can not respond to this call.
See also: QuickTime Tech Note QT4.