[vtkusers] Cannot update vtkChartXY

[Elvis Chen]

Thanks.

Your solution works for me as well.

On Thu, Oct 29, 2015 at 11:48 AM, Slaughter, Andrew E <
andrew.slaughter at inl.gov> wrote:

> I attempted to do the same thing you did (with Python VTK6.3), but it
> wouldn't work for me either. The only way I was able to get it to work as
> needed was to remove and re-create the line.
>
> I came to this solution because of this:
> http://vtk.1045678.n5.nabble.com/How-to-update-a-2d-plot-vtkChartXY-with-new-data-online-using-C-td5725677.html
>
> However, it would be great is someone who was more familiar with VTK had a
> better solution.
>
> -Andrew
>
> On Thu, Oct 29, 2015 at 9:42 AM, Elvis Chen <elvis.chen at gmail.com> wrote:
>
>> hi all,
>>
>> I am trying to utilize vtkChartXY to plot a simple 2D curve but ran into
>> some trouble, I seek your help.
>>
>> The 2D plot is a function of time and is been updated incrementally. I
>> tried to follow the example at:
>>
>> http://www.vtk.org/Wiki/VTK/Examples/Cxx/Plotting/LinePlot
>>
>> to create an initial plot. As the data come in, I extended the vtkTable,
>> and calls the renderer again, but only the initial table/plot was shown. A
>> code demonstrating is the follow. Basically what I did was:
>>
>> - create a vtkTable with 3 data point, and plot it,
>> - modify the vtkTable to include 1 more data point (4 total), and plot it
>> again,
>> - but the resulting plot only shows the original curve.
>>
>> Any help is very much appreciated,
>>
>> thanks,
>>
>>
>>
>> // arrX and arrY are vtkFloatArray
>>
>>   table->AddColumn( arrX );
>>   table->AddColumn( arrY );
>>
>> // create a table of 3 data points
>>   table->SetNumberOfRows( 3 );
>>   table->SetValue( 0, 0, 0 );
>>   table->SetValue( 0, 1, 0 );
>>   table->SetValue( 1, 0, 1 );
>>   table->SetValue( 1, 1, 1 );
>>   table->SetValue( 2, 0, 2 );
>>   table->SetValue( 2, 1, 3 );
>>
>> // render the chart
>>   view->GetRenderer()->SetBackground( 1, 1, 1 );
>>   view->GetScene()->AddItem( chart );
>>   chart->SetShowLegend( true );
>>   line = chart->AddPlot( vtkChart::LINE );
>>   line->SetInput( table, 0, 1 );
>>   line->SetColor( 1, 0, 0 );
>>   line->SetWidth( 5.0 );
>>
>> // shows a plot of 3 data point
>>   view->GetRenderer()->Render();
>>
>> // add a new point to the vtkTable
>>   table->SetNumberOfRows( 4 );
>>   table->SetValue( 0, 0, 0 );
>>   table->SetValue( 0, 1, 0 );
>>   table->SetValue( 1, 0, 1 );
>>   table->SetValue( 1, 1, 1 );
>>   table->SetValue( 2, 0, 2 );
>>   table->SetValue( 2, 1, 3 );
>>   table->SetValue( 3, 0, 5 );
>>   table->SetValue( 3, 1, 5 );
>>   table->Modified();
>>   view->Modified();
>>   line->Modified();
>>
>> // render it again, but still, only 3 data points were plot
>>   view->GetRenderer()->Render();
>>   view->GetInteractor()->Initialize();
>>   view->GetInteractor()->Start();
>>
>>
>>
>>
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/vtkusers
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20151029/c2530db3/attachment.html>