Re: FancySSCell and DirectManipulationRenderer

• To: Mathias Stümpert <atzes@xxxxxx>
• Subject: Re: FancySSCell and DirectManipulationRenderer
• From: Bill Hibbard <hibbard@xxxxxxxxxxxxxxxxx>
• Date: Wed, 20 Jun 2001 12:16:49 -0500

Hi Mathias,

This NullPointerException comes from deep inside Java3D and is probably
a Java3D problem. Line 662 of DisplayRendererJ3D.java is not a call to
draw() in the current VisAD, but there may be a line numbering difference
in your JVM.

I was however able to get direct manipulation in the SpreadSheet by
temporarily editting the BasicSSCell.setMaps() method, changing:

  VDisplay.addReference(dr[i], cmaps[i]);

to:

  VDisplay.addReferences(new DirectManipulationRendererJ3D(), dr[i], cmaps[i]);

Note this causes Exception messages in the 3-D window if the data's
MathType is not compatible with DirectManipulationRendererJ3D, but I
was able to drag the data for data with a RealType.

Changing the BasicSSCell.addReferenceImpl() method did not have any
affect for me.

Cheers,
Bill

> A few weeks ago I asked if there is a possibility to add data to a SSCell 
> with an alternativ DataRenderer especially a
> DirectManipulationRendererJ3D. Curtis told me to extend FancySSCell. Now I 
> found the time to do this and got some problems. Below are the two
> methods that extend the FancySSCell to allow the addition of a DataReference 
> with an alternative renderer:
> 
>   public String addReference(DataReferenceImpl ref, DataRenderer renderer, 
> ConstantMap[] cmaps)
>       throws VisADException, java.rmi.RemoteException {
>     SSCellData cellData;
>     synchronized (CellData) {
>       cellData = addReferenceImpl(0, ref, cmaps, "", DIRECT_SOURCE, true, 
> true, renderer);
>     }
>     return cellData.getVariableName();
>   }
> 
>   protected SSCellData addReferenceImpl(int id, DataReferenceImpl ref,
>     ConstantMap[] cmaps, String source, int type, boolean notify,
>     boolean checkErrors, DataRenderer renderer)
>       throws VisADException, java.rmi.RemoteException {
>     if (id == 0) id = getFirstFreeId();
>     if (ref == null) ref = new DataReferenceImpl(Name);
>     if (notify) sendMessage(ADD_DATA, source, ref.getData());
>     SSCellData cellData
>       new SSCellData(id, this, ref, cmaps, source, type, checkErrors);
>     CellData.add(cellData);
>     if (!IsRemote) {
>       if (HasMappings) VDisplay.addReferences(renderer, ref, cmaps);
>       synchronized (Servers) {
>         RemoteDataReferenceImpl remoteRef
>           (RemoteDataReferenceImpl) cellData.getRemoteReference();
>         int len = Servers.size();
>         for (int i=0; i<len; i++) {
>           RemoteServerImpl rs = (RemoteServerImpl) Servers.elementAt(i);
>           rs.addDataReference(remoteRef);
>         }
>       }
>     }
>     return cellData;
>   }
> 
> The addition (with a DirectManipulationRendererJ3D) of the data works without 
> problems. But if I try to move my datapoints with the right
> mouse button I get this exception:
> 
> Exception occurred during Canvas3D callback:
> java.lang.NullPointerException: null component
>  at sun.awt.windows.WDrawingSurfaceInfo.lock(Native Method)
>  at 
> javax.media.j3d.DrawingSurfaceObjectDSI.renderLock(DrawingSurfaceObjectDSI.java:60)
>  at javax.media.j3d.GraphicsContext3D.doDraw(GraphicsContext3D.java:1821)
>  at javax.media.j3d.GraphicsContext3D.draw(GraphicsContext3D.java:2059)
>  at 
> visad.java3d.DisplayRendererJ3D.drawCursorStringVector(DisplayRendererJ3D.java:662)
>  at visad.java3d.VisADCanvasJ3D.renderField(VisADCanvasJ3D.java:76)
>  at javax.media.j3d.Renderer.doWork(Renderer.java:940)
>  at javax.media.j3d.J3dThread.run(J3dThread.java:256)
> I was not able to locate the error. I'm not sure if I forget anything to 
> implement in my methods. Perhaps I should extend the SSCellData-class
> too. But then I would lose all the compatibility to any other SSCell. Are 
> there any ideas what to do?
> 
> Thanks in advance, Mathias

-- 
----------------------------------------------------------
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI  53706
hibbard@xxxxxxxxxxxxxxxxx  608-263-4427  fax: 608-263-6738
http://www.ssec.wisc.edu/~billh/vis.html

• References:
  • FancySSCell and DirectManipulationRenderer
    • From: Mathias Stümpert