I am maintaining a VS2008 C# WinForms app which uses Nevron Chart 2009.1 (v9.7.1.12). I've received a new dev machine running Win7 32-bit; previously I was using XP. After reinstalling all my dev tools I have noticed that the chart control is not fully functional when the app is recompiled under Win7. All was well under XP and no code mods have been made. I suspect it may be something to do with licensing and/or Win7 user permissions, as I found I had to run the License Key Manager as administrator in order to install my license key (otherwise I got an exception when I hit Save).

At runtime, the chart is rendered and my data is plotted OK but when the app tries to change the chart's BoundsMode or Projection property in response to a button click, nothing happens. In particular, it does not change to a 3D view when the projection is set to PerspectiveTilted. I can step through the code in the debugger and no exception is generated. It's as if the code has simply not been executed. Running VS and/or the app as administrator makes no difference.

I can't find anything in the KB about Win7-specific issues.

What am I missing?

Hi Michael,

In general even older versions of the control are compatible with 64bit versions of Windows - the only exception is the license key manager which does not read/write in the

HKEY_LOCAL_MACHINE\Software\WOW6432Node

registry node as it should, which requires you to apply the license key by code.

Regarding:

"At runtime, the chart is rendered and my data is plotted OK but when the app tries to change the chart's BoundsMode or Projection property in response to a button click, nothing happens. In particular, it does not change to a 3D view when the projection is set to PerspectiveTilted. I can step through the code in the debugger and no exception is generated. It's as if the code has simply not been executed. Running VS and/or the app as administrator makes no difference."

Do you call the control refresh method after you make changes to the control:

nChartControl1.Refresh();

Let us know if you meet any problems or have any questions.

Best Regards,
Nevron Support Team

Yes, I'm definitely calling .Refresh() on the control. The app subclasses NChartControl to add custom functionality for representing a 2D or 3D seismogram plot. Here is the routine that changes the view to one of four choices, and Refresh() is called on the last line:

private void ChangeView()
{
switch ( _view )
{
case SeismogramView.VerticalRadial:
_chart.BoundsMode = BoundsMode.Fit;
_chart.Projection.SetPredefinedProjection(PredefinedProjection.Orthogonal);
DisableTrackball();
break;

case SeismogramView.VerticalTransverse:
_chart.BoundsMode = BoundsMode.Fit;
_chart.Projection.SetPredefinedProjection(PredefinedProjection.Orthogonal);
_chart.Projection.Rotation = -90;
DisableTrackball();
break;

case SeismogramView.TransverseRadial:
_chart.BoundsMode = BoundsMode.Fit;
_chart.Projection.SetPredefinedProjection(PredefinedProjection.OrthogonalTop);
DisableTrackball();
break;

case SeismogramView.Perspective:
default:
_chart.BoundsMode = BoundsMode.None;
_chart.Projection.SetPredefinedProjection(PredefinedProjection.PerspectiveTilted);
EnableTrackball();
break;
}

this.Refresh();
}

This code has worked fine for years and hasn't been modified in any way. All I've done is recompile it on a new computer (32-bit Windows 7 Enterprise SP1, VS2008 Professional SP1).

I have also compiled the code under 32-bit Windows XP SP3 and 64-bit Windows 7 Ultimate and the chart's runtime functionality is correct in both those cases. The problem only occurs when the app is compiled on my 32-bit Win7 Enterprise laptop. Very odd indeed.

Hi Michael,

Very odd indeed - most likely this is caused by the laptop hardware drivers because it is very unlikely that there is a Windows incompatibility in the control (as its used on a large number of computers with different versions of Windows). Do you use 3D hardware acceleration in the application - if so can you test what happens if you disable it:

nChartControl1.Settings.RenderSurface = Nevron.GraphicsCore.RenderSurface.Bitmap;

Let us know if the problem persists...

Best Regards,
Nevron Support Team

I don't believe the app uses hardware acceleration. At least, the RenderSurface property is not being set anywhere, which means it defaults to Bitmap.

Other info:
The RenderDevice property is set to OpenGL.
Laptop is a Dell Precision M4700 with NVidia Quadro K2000M graphics card.

Fixed! I installed the Q2 2008 version 8.10.15.12 side by side with 2009.1 (using the same license key), referenced the 2008 dlls instead, and recompiled. The chart now works correctly. If I switch back to 2009.1 and recompile, it stops working again.

So it's due to a change between these two versions. I'll understand if you decide not to investigate a bug in a 4-year-old version of one of your products.

Anyway, my problem is solved (well, worked around) for the time being.