/// <summary>
/// Sets the new z-order value stored for <paramref name="key"/>.
/// </summary>
/// <remarks>
/// An <see cref="IUndoUnit"/> for the changed z-order is added as well if undo is
/// <see cref="GraphExtensions.IsUndoEngineEnabled">enabled</see>.
/// </remarks>
public void SetZOrder(INode key, int newZOrder)
{
var master = MasterOf(key);
int oldZOrder = 0;
zOrders.TryGetValue(master, out oldZOrder);
if (oldZOrder != newZOrder)
{
if (MasterGraph.IsUndoEngineEnabled())
{
MasterGraph.AddUndoUnit("Undo Z-order Change", "Redo Z-order Change",
() => {
SetZOrderCore(master, oldZOrder);
Update(master);
}, () => {
SetZOrderCore(master, newZOrder);
Update(master);
});
}
SetZOrderCore(master, newZOrder);
OnZOrderChanged(key, newZOrder, oldZOrder);
}
}
private static IBend CreateBends([NotNull] IGraph graph, [NotNull] IEdge edge, int segmentIndex, double ratio,
[NotNull] IListEnumerable <IPoint> pathPoints)
{
//Create 3 bends and adjust the neighbors
//The first bend we need to touch is at startIndex
var startIndex = segmentIndex * 3;
//This holds the new coordinates left and right of the split point
//We don't actually need all of them, but this keeps the algorithm more straightforward.
var left = new PointD[4];
var right = new PointD[4];
//Determine the new control points to cleanly split the curve
GetCubicSplitPoints(ratio,
new[] {
pathPoints[startIndex].ToPointD(), pathPoints[startIndex + 1].ToPointD(),
pathPoints[startIndex + 2].ToPointD(), pathPoints[startIndex + 3].ToPointD()
}, left, right);
//Previous control point - does always exist as a bend, given our precondition
var previousBend = edge.Bends[startIndex];
//Next control point - also always exists given the precondition for bend counts (i.e. there have to be at least two)
var nextBend = edge.Bends[startIndex + 1];
//We create the three new bends between previous bend and next bend and adjust these two.
//We don't have to adjust more bends, since we just have a cubic curve.
IBend bendToMove;
var engine = graph.GetUndoEngine();
//Wrap everything into a single compound edit, so that everything can be undone in a single unit
using (var edit = graph.BeginEdit("Create Bezier Bend", "Create Bezier Bend")) {
try {
//Adjust the previous bend - given the split algorithm, its coordinate is in left[1]
//(left[0] is actually kept unchanged from the initial value)
var oldPrevLocation = previousBend.Location.ToPointD();
var newPrevLocation = left[1];
graph.SetBendLocation(previousBend, newPrevLocation);
// Add unit to engine
graph.AddUndoUnit("Set bend location", "Set bend location",
() => graph.SetBendLocation(previousBend, oldPrevLocation),
() => graph.SetBendLocation(previousBend, newPrevLocation));
//Insert the new triple, using the values from left and right in order
graph.AddBend(edge, left[2], startIndex + 1);
bendToMove = graph.AddBend(edge, left[3], startIndex + 2);
//right[0] == left[3], so right[1] is the next new control point
graph.AddBend(edge, right[1], startIndex + 3);
//Adjust the next bend
var oldNextLocation = nextBend.Location.ToPointD();
var newNextLocation = right[2];
graph.SetBendLocation(nextBend, newNextLocation);
// Add unit to engine
graph.AddUndoUnit("Set bend location", "Set bend location",
() => graph.SetBendLocation(nextBend, oldNextLocation),
() => graph.SetBendLocation(nextBend, newNextLocation));
} catch {
//Cancel the edit in case anything goes wrong.
edit.Cancel();
throw;
}
}
return(bendToMove);
}