XmDirectionMatchPartial compares d1 and d2 along the
direction component specified by dmask.
For example, if dmask equals XmVERTICAL_MASK, then
the function will compare only the vertical components of d1
and d2.
d1
Specifies an XmDirection value to check.
d2
Specifies an XmDirection value to check.
dmask
Specifies the direction component along which d1 and d2
are to be checked. Appropriate values for dmask are
XmHORIZONTAL_MASK,
XmVERTICAL_MASK,
and
XmPRECEDENCE_MASK.
RETURN VALUES
Returns True if the d1 and d2 match in the component
specified by dmask; otherwise, returns False.