private Transform CalcEdgeTransform(int edgeIndex)
{
ShapeEdge edge = this.shape.Structure.Edges[edgeIndex];
Vector pos1 = this.shape.VertexPositions[edge.Index1];
Vector pos2 = this.shape.VertexPositions[edge.Index2];
Vector middlePos = 0.5 * (pos1 + pos2);
double edgeLength = pos1.DistanceToPoint(pos2);
double angle = Vector.AngleBetween(Vector.UnitX, pos2 - pos1);
TransformGroup result = new TransformGroup();
result.Children.Add(new TranslateTransform(-0.5, -0.5));
result.Children.Add(new ScaleTransform(edgeLength, this.shape.EdgeWidths[edgeIndex]));
result.Children.Add(new RotateTransform(MathHelper.ToDegrees(angle)));
result.Children.Add(new TranslateTransform(middlePos.X, middlePos.Y));
return(result);
}
