I am currently routing a multi layer board and the level of EMI shielding to be provided by the internal ground plane is critical. I don't want large gaps to be formed in the plane where two vias may be close to one another. I have been moving vias away from each other where possible but in some places there seems to be ample room for the plane to fill between vias but when I flood them it's not doing so. See the attached picture for an example of what I am talking about. Is there some setting where I can force it to fill more closely around the openings?