Hi Stoyan,

Our users have managed to create a diagram that is very quickly throwing an out of memory exception as soon as it is zoomed out using the mouse wheel.

Here's the call stack:

************** Exception Text **************
System.OutOfMemoryException: Out of memory.
   at System.Drawing.Graphics.CheckErrorStatus(Int32 status)
   at System.Drawing.Graphics.DrawPath(Pen pen, GraphicsPath path)
   at MindFusion.Drawing.GdiGraphics.DrawPath(Pen pen, GraphicsPath path)
   at MindFusion.Diagramming.ShapeNode.DrawOutline(DrawParams dp)
   at MindFusion.Diagramming.ShapeNode.DrawShape(IGraphics graphics, RectangleF rc, Boolean shadow, Brush mfBrush, Pen mfPen, RenderOptions options)
   at MindFusion.Diagramming.ShapeNode.DrawShadow(IGraphics graphics, RenderOptions options)
   at MindFusion.Diagramming.Diagram.DrawItemWithShadow(IGraphics graphics, DiagramItem item, Boolean relatedItems)
   at MindFusion.Diagramming.Diagram.DrawItems(IGraphics graphics, RectangleF clipRect, Boolean modfBackBuf)
   at MindFusion.Diagramming.Diagram.Draw(IGraphics graphics, RenderOptions options, RectangleF clipRect, Boolean noModifiedItems)
   at MindFusion.Diagramming.WinForms.DiagramView.DrawDiagram(IGraphics graphics, RectangleF clip, Boolean noModifiedItems)
   at MindFusion.Diagramming.WinForms.DiagramView.OnPaint(PaintEventArgs pe)
   at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer)
   at System.Windows.Forms.Control.WmPaint(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
 

I know that I'm not providing a lot of info but any idea what can cause this and/or what to look for?

EDIT: Actually I can zoom without the exception as long as i want between 200% and 50% but as soon as I try to set the zoom level to 40% i get the out of memory exception.
EDIT2: Setting the zoom level to 39% or to 41% works but setting it to 40% immediately generates the exception!!

Yes indeed it's crashing on the drawing of a node that has

ShapeNode.Pen.Width = 0;
                ShapeNode.Pen.DashStyle = DashStyle.Dash; 

If I set

diagramView.SmoothingMode = SmoothingMode.None; 

it no longer crashes, so its definitely what you were suggesting above. What is strange is that I have many other nodes with the same properties on this diagram and only this specific node is generating the exception. Is is something related to the size of the node?

I have also found the property CatchGdiPlusExceptions (BTW the documentation is incorrect for this property in the CHM, you may want to fix it) but as you said setting it to true doesn't fix the issue.

On the PM page you can find updated version that catches these exceptions for nodes too. We can't see any adverse effect from catching and ignoring them, the borders still seem to be drawn correctly and there isn't any obvious memory usage spike. Our theory is that GDI+ native code returns some status code that's not interpreted correctly by the .NET wrapper class, and the wrapper unnecessarily throws a CLR out-of-mem exception for that code.

I hope that helps,
Stoyan

You can find updated .cs files on the PM page. Search for this line to find the relevant changes:

if (options.CatchGdiPlusExceptions)

Regarding moving to the new styling system, you can find some information here (check the Beware of Null ... part):
http://www.mindfusion.eu/onlinehelp/flowchartnet/index.htm?Changes_in_Control_s_...

So if you have code like this:
node.Pen.Color = Color.Black;
node.Pen.Width = 3;

you can replace it with
node.Pen = new Pen(Color.Black, 3);

or create node.Style and set Stroke and StrokeThickness in the Style.

When custom drawing, do not use Pen, Brush and Font directly, but EffectivePen, EffectiveBrush and EffectiveFont to get values resolved first from local properties if set, then styles and finally themes.

I hope that helps,
Stoyan