/// <summary>
/// Finds the closest available position to <see cref="pos"/> in <see cref="spaceUsage"/> on the x axis <see cref="searchAxis"/>
/// </summary>
/// <param name="spaceUsage">layout object</param>
/// <param name="pos">position to look for</param>
/// <param name="searchAxis">x axis to look for</param>
/// <returns>closest position of pos in the searchAxis, null if cannot be found</returns>
protected XyPosition?FindClosest(NodeViewModel[,] spaceUsage, XyPosition pos, int searchAxis)
{
int height = spaceUsage.GetLength(1);
int?closestY = null;
int distance = int.MaxValue;
for (int i = 0; i < height; i++)
{
NodeViewModel model = spaceUsage[searchAxis, i];
if (model != null)
{
continue;
}
int testDistance = Math.Abs(pos.Y - i);
if (testDistance < distance)
{
distance = testDistance;
closestY = i;
}
}
if (closestY != null)
{
return(new XyPosition(searchAxis, closestY.Value));
}
return(null);
}
/// <summary>
/// Finds the closest available position to <see cref="origin"/> in <see cref="spaceUsage"/> for <see cref="destination"/>
/// </summary>
/// <param name="spaceUsage">layout object</param>
/// <param name="origin">node to start from</param>
/// <param name="destination">target node placement</param>
/// <returns>closest position of <see cref="destination"/> to <see cref="origin"/>, null if cannot be found</returns>
protected XyPosition?FindClosest(NodeViewModel[,] spaceUsage, NodeViewModel origin, NodeViewModel destination)
{
XyPosition pos = SpaceUsagePosition(spaceUsage, origin);
int originLevel = m_nodeColumnLookup[origin];
int destinationLevel = m_nodeColumnLookup[destination];
if (originLevel > destinationLevel)
{
return(FindClosest(spaceUsage, pos, pos.X - 1));
}
else if (originLevel < destinationLevel)
{
return(FindClosest(spaceUsage, pos, pos.X + 1));
}
return(null);
}
