Slow attribute updates in large attack graphs

[tobi18991]

For large attack graphs, e.g., 30 nodes, 100 edges, it takes a long time until the whole graph was updated.

The problem lies in the AttributeRenderer.recalculateAllCells() method. It starts a recursive call to refresh cell attributes from EVERY cell. Hence, many cells are updated several times even though (theoretically) one call would be sufficient.

To fix this issue, a mechanism to mark already visited nodes would be needed and a node's attributes shall only be updated when ALL children were already updated.

Tips for implementation: The root of the mxGraph structure is NOT the root of the (visible) graph.