/// <summary>
/// Low-level draw method used by other rendering methods.
/// </summary>
/// <param name="visitor">the draw visitor</param>
/// <param name="bounds">a bound rendering element</param>
/// <param name="zoom">if the diagram is zoomed at all</param>
/// <param name="viewBounds">the view bounds - the root will be centered in the bounds</param>
protected void Draw(IDrawVisitor visitor, double zoom, Bounds bounds, Rect viewBounds)
{
var modelScale = zoom * model.GetScale();
var zoomToFit = Math.Min(viewBounds.Width / (bounds.Width * modelScale), viewBounds.Height / (bounds.Height * modelScale));
var transform = Matrix.Identity;
// setup up transform
transform.TranslatePrepend(viewBounds.CenterX(), viewBounds.CenterY());
transform.ScalePrepend(modelScale, -modelScale);
// default is shrink only unless specified
if (model.GetFitToScreen() || zoomToFit < 1)
{
transform.ScalePrepend(zoomToFit, zoomToFit);
}
transform.TranslatePrepend(-(bounds.MinX + bounds.MaxX) / 2, -(bounds.MinY + bounds.MaxY) / 2);
// not always needed
var fontManager = new WPFFontManager
{
Zoom = zoomToFit
};
visitor.RendererModel = model;
visitor.FontManager = fontManager;
visitor.Visit(bounds.Root, new MatrixTransform(transform));
}
public virtual void AcceptDrawVisitor(int x, int y, IDrawVisitor visitor)
{
visitor.Visit(this, x, y);
}
