/// <summary>
/// unlinks a target from a source. Either src or target has this shape as owner
/// </summary>
/// <param name="src">the link source</param>
/// <param name="target">the link target</param>
public override void OnUnlink(ShapeLink src, ShapeLink target)
{
base.OnUnlink(src, target);
// perform the unlinking on the engine objects
if (target.OwnerShape == this)
{
ConstraintShape constraint = src.OwnerShape as ConstraintShape;
if (constraint != null && HasEngineInstance() && constraint.HasEngineInstance()) // at least the engine instance of the constraint can be null
{
EnginePGroup.RemoveConstraint(constraint._engineInstance as EngineInstanceConstraint);
}
}
}
/// <summary>
/// Perform the actual linking. Either src or target has this shape as owner
/// </summary>
/// <param name="src">the link source</param>
/// <param name="target">the link target</param>
public override void OnLink(ShapeLink src, ShapeLink target)
{
base.OnLink(src, target); // adds to collections
if (HasEngineInstance())
{
EnginePGroup.OnLinksChanged();
}
// perform the linking on the engine objects
if (target.OwnerShape == this)
{
ConstraintShape constraint = src.OwnerShape as ConstraintShape;
if (constraint != null && HasEngineInstance() && constraint.HasEngineInstance()) // at least the engine instance of the constraint can be null
{
EnginePGroup.AddConstraint(constraint._engineInstance as EngineInstanceConstraint);
}
}
}