public void LoadSigma(SigmaGraphModel graph)
{
nodes = graph.Nodes?.Select(n => new V8NodeModel()
{
id = n.Id, x = n.X, y = n.Y, size = n.Size
}).ToArray() ?? new V8NodeModel[0];
edges = graph.Edges?.Select(e => new V8EdgeModel()
{
id = e.Id, source = e.Source, target = e.Target
}).ToArray() ?? new V8EdgeModel[0];
}
/// <summary>
/// Assumes layout has been already applied
/// Note: method mutates graph and graphLayout
/// </summary>
public void ImproveAppliedLayout(SigmaGraphModel graph, GraphLayout graphLayout, LayoutSettings layoutSettings, TimeSpan duration)
{
using (var engine = new V8ScriptEngine())
{
try
{
var v8Graph = new V8GraphModel();
v8Graph.LoadSigma(graph);
engine.AddHostObject("log", _log);
engine.Execute("var graph = " + JsonConvention.SerializeObject(v8Graph) + ";");
engine.Execute("var settings = " + JsonConvention.SerializeObject(layoutSettings) + ";");
engine.Execute("var duration = " + JsonConvention.SerializeObject(duration.TotalMilliseconds) + ";");
var baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
var forceAtlas2 = engine.Compile(File.ReadAllText($@"{baseDirectory}\App\Graph\Layout\ForceAtlas2.js"));
var serviceScript = engine.Compile(File.ReadAllText($@"{baseDirectory}\App\Graph\Layout\GraphLayoutService.js"));
engine.Execute(forceAtlas2);
engine.Execute(serviceScript);
var nodesJson = engine.Evaluate("JSON.stringify(nodes)").ToString();
var nodes = JsonConvention.DeserializeObject <V8NodeModel[]>(nodesJson);
for (int i = 0; i < nodes.Length; i++)
{
var node = graph.Nodes[i];
node.X = nodes[i].x;
node.Y = nodes[i].y;
var id = node.Entity;
if (id.HasValue)
{
graphLayout[id.Value] = new GraphLayout.Coords()
{
X = nodes[i].x,
Y = nodes[i].y
};
}
}
}
catch (ScriptEngineException e)
{
_log.Error("V8 exception: " + e.ErrorDetails);
throw;
}
}
}
private bool ApplyLayout(SigmaGraphModel graph, GraphLayout graphLayout)
{
var allNodesCovered = true;
var rnd = new Random();
foreach (var node in graph.Nodes)
{
GraphLayout.Coords coords;
// should we interpolate vertex position for group by clause
if (node.Props != null && node.Props.ContainsKey("members") &&
graph.Data != null && graph.Data.ContainsKey("grouped_vertices"))
{
if (InterpolateCoords(
node.Props["members"] as HashSet <int>,
graph.Data["grouped_vertices"] as List <PropertyVertexModel>,
graphLayout, rnd, out coords))
{
node.X = coords.X;
node.Y = coords.Y;
}
else
{
node.X = rnd.NextDouble();
node.Y = rnd.NextDouble();
allNodesCovered = false;
}
}
// no interpolation but layout available
else if (node.Entity.HasValue && graphLayout != null && graphLayout.TryGetValue(node.Entity.Value, out coords))
{
node.X = coords.X;
node.Y = coords.Y;
}
else
{
node.X = rnd.NextDouble();
node.Y = rnd.NextDouble();
allNodesCovered = false;
}
}
return(allNodesCovered);
}
/// <summary>
/// 1) jeśli nie layoutu ma to utwórz nowy layout, synchronicznie odpal layout i dodaj do bazy
/// 2) jeśli jest już layout to go wczytaj
/// 2a) jeśli któryś z węzłow nie ma współżędnych to synchronicznie odpal layout ale na krótkie 0.5 sekundy
/// 2b) zakolejkuj kolejny krok rozłożenia z niskim priorytetem
/// </summary>
public async Task LayoutGraph(SigmaGraphModel graph, LayoutTask layoutTask, TimeSpan?duration)
{
if (Guid.Empty.Equals(layoutTask.Query.NetworkId))
{
throw new ArgumentNullException(nameof(layoutTask.Query.NetworkId));
}
if (graph.Nodes == null)
{
return;
}
var networkId = layoutTask.Query.NetworkId;
var layout = await _repository.Db.Layouts.SingleOrDefaultAsync(l => l.NetworkId == networkId && l.Key == layoutTask.Query.LayoutKey);
// Ad 1
if (layout == null)
{
lock (LayoutLock)
{
// prevent entering here from many threads
layout = _repository.Db.Layouts.SingleOrDefault(
l => l.NetworkId == networkId && l.Key == layoutTask.Query.LayoutKey);
if (layout == null)
{
layout = new Entities.Layout()
{
Id = Guid.NewGuid(),
NetworkId = networkId,
Key = layoutTask.Query.LayoutKey
};
_repository.Db.Layouts.Add(layout);
_repository.Db.SaveChanges();
}
}
ApplyLayout(graph, null);
var graphLayout = new GraphLayout();
ImproveAppliedLayout(graph, graphLayout, layoutTask.Settings,
duration ?? _firstTimeLayoutDuration);
// save layout
layout.GraphLayout = graphLayout;
_repository.Db.SaveChanges();
}
else
// Ad 2
{
var graphLayout = layout.GraphLayout;
if (!ApplyLayout(graph, graphLayout))
{
// ad 2a
ImproveAppliedLayout(graph, graphLayout, layoutTask.Settings, duration ?? _missingNodesImproveLayoutDuration);
layout.GraphLayout = graphLayout;
await _repository.Db.SaveChangesAsync();
}
else
{
// ad 2b
if (Background == null)
{
ImproveAppliedLayout(graph, graphLayout, layoutTask.Settings, duration ?? _missingNodesImproveLayoutDuration);
layout.GraphLayout = graphLayout;
await _repository.Db.SaveChangesAsync();
}
else
{
_log.Debug("Scheduling background layout");
if (layoutTask.ModifyLayout)
{
Background.Execute(new ImproveLayoutCommand()
{
Task = layoutTask,
Duration = duration ?? _improveLayoutInBackgroundDuration
}, new BackgroundPrincipal(Auth.UserName));
}
}
}
}
}
