[vtkusers] Error in the visualisation of the lookuptable for my scalarbarwidget -> need help

[Michael Dussere]

Hi Stephan,

There is no big deal, you just need to call "Build()" on you lookup 
table after configuring it.

// set the range

    m_pLut->SetTableRange(0.0, 1.0);

// set hue range to full colorrange

    m_pLut->SetHueRange(0.0, 1.0);

// building the lookup table

    m_pLut->Build();


Michael



Franke, Stephan wrote:
> Hi,
> 
>  
> 
> I need your help. I use for my application the vtkScalarBarWidget to map
> 
> scalar values on colour values. When I initialize my lookuptable I get 
> the colour
> 
> gradient shown in the attached picture. What I expect is a black coloured
> 
> lookuptable but that’s not the case. I get at the beginning of the 
> lookuptable this fracment of red.
> 
> My Initroutine looks like this. Someone has a hint for me what I am 
> doing wrong?
> 
> Thanks for your help.
> 
>  
> 
> void Colortable::InitLookupTable()
> 
> {
> 
>     // generate for the first time a black/white lookuptable for the 
> colortable
> 
>     m_pLut = vtkLookupTable::New();
> 
>     if(m_pLut == NULL)
> 
>         // TODO error message
> 
>         return;
> 
>  
> 
>     // set the range
> 
>     m_pLut->SetTableRange(0.0, 1.0);
> 
>     // set hue range to full colorrange
> 
>     m_pLut->SetHueRange(0.0, 1.0);
> 
>     // set full saturation (0=white)
> 
>     //m_pLut->SetSaturationRange(0.0, 1.0);
> 
>     // set the range on some brightness (0=black)
> 
>     //m_pLut->SetValueRange(0.0, 1.0);
> 
>  
> 
>     // set the lookuptable
> 
>     m_pBar->GetScalarBarActor()->SetLookupTable(m_pLut);
> 
>    
> 
>     // set the title of the colortable
> 
>     m_pBar->GetScalarBarActor()->SetTitle("EMPTY");
> 
>  
> 
>     // set the sizes for the colortable
> 
>     m_pBar->GetScalarBarActor()->SetHeight(0.08);
> 
>     m_pBar->GetScalarBarActor()->SetWidth(0.5);
> 
>     //m_pBar->GetScalarBarActor()->SetLabelFormat("%6.0f");
> 
>     m_pBar->GetScalarBarActor()->SetMaximumNumberOfColors(20);
> 
>  
> 
>     // set position inside the rendering window and the orientation of 
> the table
> 
>     
> //m_pBar->GetScalarBarActor()->GetPositionCoordinate()->SetValue(0.05, 
> 0.01);
> 
>     m_pBar->GetScalarBarActor()->GetPositionCoordinate()->
> 
>         SetCoordinateSystemToNormalizedViewport();
> 
>     m_pBar->GetScalarBarActor()->GetPositionCoordinate()->
> 
>         SetValue(0.25, 0.01);
> 
>     m_pBar->GetScalarBarActor()->SetOrientationToHorizontal();
> 
>  
> 
>     // assign the colortable to the rendering window
> 
>     m_pBar->SetInteractor(m_pDocument->GetRenderWindow()->GetInteractor());
> 
> }
> 
>  
> 
> Dipl. Ing.  Stephan Franke
> Virtuelles Prototyping (VPT)
> 
> *INPRO* Innovationsgesellschaft für
> fortgeschrittene Produktionssysteme
> in der Fahrzeugindustrie mbH
> Hallerstraße 1, D-10587 Berlin
> 
> Telefon:  +49 (0)30 399 97-278
> Fax:         +49 (0)30 399 97-117
> E-Mail:     Stephan.Franke at inpro.de <mailto:Stephan.Franke at inpro.de>
> Web:        www.inpro.de <http://www.inpro.de/>
> 
>  
> 
> 
> ------------------------------------------------------------------------
> 
> 
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