/// <summary>
/// Gets an <see cref="IBoundsProvider"/> implementation that can yield
/// this arrow's bounds if painted at the given location using the
/// given direction for the given edge.
/// </summary>
/// <param name="edge">The edge this arrow belongs to</param>
/// <param name="atSource">Whether this will be the source arrow</param>
/// <param name="anchor">The anchor point for the tip of the arrow</param>
/// <param name="directionVector">The direction the arrow is pointing in</param>
/// <returns>
/// an implementation of the <see cref="IBoundsProvider"/> interface that can
/// subsequently be used to query the bounds. Clients will always call
/// this method before using the implementation and may not cache the instance returned.
/// This allows for applying the flyweight design pattern to implementations.
/// </returns>
public IBoundsProvider GetBoundsProvider(IEdge edge, bool atSource, PointD anchor, PointD directionVector)
{
// Get the edge's thickness
MySimpleEdgeStyle style = edge.Style as MySimpleEdgeStyle;
if (style != null)
{
Thickness = style.PathThickness;
}
this.anchor = anchor;
this.direction = directionVector;
return(this);
}
/// <summary>
/// Gets an <see cref="IVisualCreator"/> implementation that will paint
/// this arrow at the given location using the given direction
/// for the given edge.
/// </summary>
/// <param name="edge">The edge this arrow belongs to</param>
/// <param name="atSource">Whether this will be the source arrow</param>
/// <param name="anchor">The anchor point for the tip of the arrow</param>
/// <param name="direction">The direction the arrow is pointing in</param>
/// <returns>
/// Itself as a flyweight.
/// </returns>
public IVisualCreator GetVisualCreator(IEdge edge, bool atSource, PointD anchor, PointD direction)
{
// Get the edge's thickness
MySimpleEdgeStyle style = edge.Style as MySimpleEdgeStyle;
if (style != null)
{
thickness = style.PathThickness;
}
else
{
thickness = Thickness;
}
this.anchor = anchor;
this.direction = direction.Normalized;
return(this);
}
/// <summary>
/// Configures the thickness to use for the next visual creation.
/// </summary>
/// <param name="edge">The edge to read the thickness from.</param>
private void ConfigureThickness(IEdge edge)
{
// Get the edge's thickness
MySimpleEdgeStyle style = edge.Style as MySimpleEdgeStyle;
double oldThickness = thickness;
if (style != null)
{
thickness = style.PathThickness;
}
else
{
thickness = Thickness;
}
// see if the old arrow figure needs to be invalidated...
if (thickness != oldThickness)
{
arrowFigure = null;
}
}