@Override
	@SuppressWarnings("unchecked")
	public void mouseReleased(MouseEvent e) {
		VisualizationViewer<V, E> vv = (VisualizationViewer<V, E>) e.getSource();
		if (e.getModifiersEx() == this.addToSelectionModifiers) {
			if (down != null) {
				Point2D out = e.getPoint();

				if (vertex == null && heyThatsTooClose(down, out, 5) == false) {
					pickContainedVertices(vv, down, out, false);
				}
			}
		}
		else {

			// Mouse released without the 'add to selection' modifiers. See if we have been dragging
			if (down != null) {
				// check to see if we were dragging (no vertex picked and a large enough rectangle)
				Point2D out = e.getPoint();
				if (vertex == null && heyThatsTooClose(down, out, 5) == false) {
					pickContainedVertices(vv, down, out, true);
				}
			}

		}

		down = null;
		vertex = null;
		edge = null;
		rect.setFrame(0, 0, 0, 0);
		vv.removePostRenderPaintable(lensPaintable);
		vv.repaint();
	}
If the mouse is dragging a rectangle, pick the
Vertices contained in that rectangle

clean up settings from mousePressed
Ghidra/Framework/Graph/src/main/java/ghidra/graph/viewer/event/mouse/JungPickingGraphMousePlugin.java