Constraints in FastIncrementalLayoutSettings

Hello!

I am trying to create layout for a graph using fast incremental algorithm, but can't make constraints work: they are not called at all during algorithm execution.

What am I doing wrong?

Code is as follows:

// creating settings object
var layoutSettings = new FastIncrementalLayoutSettings();

// creating and adding constraint
var c = new HorizontalSeparationConstraint(leftNode, rightNode, 200);
layoutSettings.AddStructuralConstraint(c);

// executing layout calculation
Microsoft.Msagl.Miscellaneous.LayoutHelpers.CalculateLayout(graph, layoutSettings, null);

I am sure that my node objects are in graph.

With a little research I have found that settings object is being copied before calculations through constructor public FastIncrementalLayoutSettings(FastIncrementalLayoutSettings previousSettings), and the collection of constraints are not being transferred into new object there. Meaning, there are no constraints present during calculations.

If I copy reference to the collection into new object, then I encounter exception:
hc.LeftNode.AlgorithmData has type AlgorithmDataNodeWrap, but is casted to FiNode in AxisSolver.AddStructuralConstraints() method, resulting in exception.

Am I using library in a wrong way or is there an actual bug?
I really need to get that constraints working.

Start by reproducing the provided example with FastIncrementalLayoutSettings and inspect the FastIncrementalLayoutSettings(FastIncrementalLayoutSettings previousSettings) constructor. Then trace AxisSolver.AddStructuralConstraints() and the constraint collection and node AlgorithmData types. Done means structural constraints are retained through layout calculation and execute without the reported cast exception.