i use the 'group as mask' funciton, (held in modify-mask) to make a shape. it works perfeclty. i.e when you place a vector over any object and then select the vecotor plus the object and then clcik the 'group as mask' any part of the object that was not covered by the vector will be masked ( in other words, no longer visible).
my question is this; how do i reverse the process. i.e i want the part that is covered by the vecotor object to be masked and the part not covered by the vector object to be visible
Here you go: First, ungroup the mask (Modify > Ungroup). Then select the top vector object and, in the Path panel, choose Invert Paths (the first option in the second row of the Alter Paths section). Now reselect both objects and choose Modify > Mask > Group As Mask.