public class Zoombox : ContentControl

{

    private Canvas container = null;

    private ScaleTransform zoom = null;

    private TranslateTransform pan = null;

    public Zoombox()

    {

        this.DefaultStyleKey = typeof(Zoombox);

        ZoomMargin = 10;

    }

    public override void OnApplyTemplate()

    {

        base.OnApplyTemplate();

        container = (Canvas)GetTemplateChild("Container");

        zoom = (ScaleTransform)GetTemplateChild("Zoom");

        pan = (TranslateTransform)GetTemplateChild("Pan");

    }

    public void ZoomTo(Rect rect)

    {

        rect.X = rect.X - ZoomMargin / 2;

        rect.Y = rect.Y - ZoomMargin / 2;

        rect.Width = rect.Width + ZoomMargin;

        rect.Height = rect.Height + ZoomMargin;

        double factor = Math.Min(container.ActualWidth / rect.Width, container.ActualHeight / rect.Height);

        zoom.ScaleY = zoom.ScaleX = factor;

        pan.X = (container.ActualWidth - rect.Width * factor) / 2 - rect.X * factor;

        pan.Y = (container.ActualHeight - rect.Height * factor) / 2 - rect.Y * factor;

    }

    public void ZoomTo(Rect rect, TimeSpan duration)

    {

        ZoomTo(rect, duration, null);

    }

    public void ZoomTo(Rect rect, TimeSpan duration, IEasingFunction func)

    {

        rect.X = rect.X - ZoomMargin / 2;

        rect.Y = rect.Y - ZoomMargin / 2;

        rect.Width = rect.Width + ZoomMargin;

        rect.Height = rect.Height + ZoomMargin;

        double factor = Math.Min(container.ActualWidth / rect.Width, container.ActualHeight / rect.Height);

        double panx = (container.ActualWidth - rect.Width * factor) / 2 - rect.X * factor;

        double pany = (container.ActualHeight - rect.Height * factor) / 2 - rect.Y * factor;

        Storyboard sb = new Storyboard();

        DoubleAnimation zoomx_anim = new DoubleAnimation() { To = factor, Duration = duration, EasingFunction = func };

        Storyboard.SetTarget(zoomx_anim, zoom);

        Storyboard.SetTargetProperty(zoomx_anim, new PropertyPath("ScaleX"));

        DoubleAnimation zoomy_anim = new DoubleAnimation() { To = factor, Duration = duration, EasingFunction = func };

        Storyboard.SetTarget(zoomy_anim, zoom);

        Storyboard.SetTargetProperty(zoomy_anim, new PropertyPath("ScaleY"));

        DoubleAnimation panx_anim = new DoubleAnimation() { To = panx, Duration = duration, EasingFunction = func };

        Storyboard.SetTarget(panx_anim, pan);

        Storyboard.SetTargetProperty(panx_anim, new PropertyPath("X"));

        DoubleAnimation pany_anim = new DoubleAnimation() { To = pany, Duration = duration, EasingFunction = func };

        Storyboard.SetTarget(pany_anim, pan);

        Storyboard.SetTargetProperty(pany_anim, new PropertyPath("Y"));

        sb.Children.Add(zoomx_anim);

        sb.Children.Add(zoomy_anim);

        sb.Children.Add(panx_anim);

        sb.Children.Add(pany_anim);

        sb.Begin();

    }

    public double ZoomCache

    {

        get

        {

            if (((UIElement)Content).CacheMode == null)

                return 0;

            else

                return ((BitmapCache)((UIElement)Content).CacheMode).RenderAtScale;

        }

        set

        {

            if (value == 0)

                ((UIElement)Content).CacheMode = null;

            else

                ((UIElement)Content).CacheMode = new BitmapCache() { RenderAtScale = value };

        }

    }

    public double ZoomMargin { get; set; }

}