private static void StretchEdge(Edge edge, double length)
{
Vector2 directionNormalized = Vector2.Normalize(edge.GetDirection());
double lengthMultiplier = length - edge.Length;
Vector2 offset = directionNormalized * (float)lengthMultiplier;
edge.End.Position = edge.End.Position.Add(new Point((int)Math.Round(offset.X), (int)Math.Round(offset.Y)));
}
private static bool AreEdgesPerpendicular(Edge e1, Edge e2)
{
Vector2 dir1 = e1.GetDirection();
Vector2 dir2 = e2.GetDirection();
//normalizing in order to have length independent epsilon
return(Math.Abs(Vector2.Dot(Vector2.Normalize(dir1), Vector2.Normalize(dir2))) < RelationConstants.PerpendicularDotEpsilon);
}
private static void RotateNeighboursToPerpendicular(Edge first, Edge second)
{
var temp = new Edge(first.Begin, second.End);
var middle = temp.GetSplitVertex();
var oldPos = first.End.Position;
first.End.Position = middle.Position;
var direction = first.GetDirection();
var positionFirst = first.End.Position.Add(new Point(-(int)Math.Round(direction.Y), (int)Math.Round(direction.X)));
var positionSecond = first.End.Position.Add(new Point((int)Math.Round(direction.Y), -(int)Math.Round(direction.X)));
first.End.Position = positionFirst.DistanceSquaredTo(oldPos) > positionSecond.DistanceSquaredTo(oldPos) ? positionSecond : positionFirst;
}
private static void RotateToPerpendicular(Edge edge, Edge relationEdge)
{
var direction = relationEdge.GetDirection();
if (edge.Length < 3)
{
StretchEdge(edge, 4);
}
var perpFirst = new Vector2(-direction.Y, direction.X);
var perpSecond = new Vector2(direction.Y, -direction.X);
perpFirst = Vector2.Normalize(perpFirst) * (float)edge.Length;
perpSecond = Vector2.Normalize(perpSecond) * (float)edge.Length;
var posFirst = edge.Begin.Position.Add(new Point((int)Math.Round(perpFirst.X), (int)Math.Round(perpFirst.Y)));
var posSecond = edge.Begin.Position.Add(new Point((int)Math.Round(perpSecond.X), (int)Math.Round(perpSecond.Y)));
edge.End.Position = posFirst.DistanceSquaredTo(edge.End.Position) > posSecond.DistanceSquaredTo(edge.End.Position) ? posSecond : posFirst;
}