bill, i also think that the DecimatePro destroys the cell scalar data. <br>The example you provide is good, and what i want is render all the structure in the dataset.<br> I record it ! Though, i do not understand them totally.<br>
<br>thanks<br>wenwu <br><br><br><br><div class="gmail_quote">On Sat, Apr 17, 2010 at 8:14 PM, Bill Lorensen <span dir="ltr"><<a href="mailto:bill.lorensen@gmail.com">bill.lorensen@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
This makes sense to me. DecimatePro removes cells and in doing so<br>
destroys the cell scalar data. Another alternative is to split the<br>
cubes generated polydata into separate polydata using vtkThreshold.<br>
Look at the example:<br>
<a href="http://www.vtk.org/Wiki/VTK/Examples/Medical/Cxx/GenerateModelsFromLabels" target="_blank">http://www.vtk.org/Wiki/VTK/Examples/Medical/Cxx/GenerateModelsFromLabels</a><br>
<font color="#888888"><br>
Bill<br>
</font><div><div></div><div class="h5"><br>
On Sat, Apr 17, 2010 at 6:09 AM, 朱文武 <<a href="mailto:cool.wenwu@gmail.com">cool.wenwu@gmail.com</a>> wrote:<br>
> hey, bill, thanks very much ! I find the culprit !<br>
> Firstly, i try mapper->SetInput(cube->GetOutput()). And, the result is<br>
> satisfactory. I reach the destination. So, i think there are must be some<br>
> problems in the pipeline.<br>
> Secondely, i remove the vtkDecimatePr from the pipeline, and surprisedly<br>
> find that the the actor is colored correctly. And if this class is put back,<br>
> the result is opposite. However, i can not find the reason why this class<br>
> has a bad effect on the color of cells.<br>
><br>
> In conclusion, i remove that class, and the program runs correctly. Your<br>
> think pattern in solving problems in the vtk programming style is great!<br>
> Have a good weekend!<br>
><br>
><br>
> Thanks<br>
> Wenwu<br>
><br>
><br>
> On Sat, Apr 17, 2010 at 9:49 AM, 朱文武 <<a href="mailto:cool.wenwu@gmail.com">cool.wenwu@gmail.com</a>> wrote:<br>
>><br>
>> thanks ,bill! i will try, then tell you the result .<br>
>><br>
>> On Sat, Apr 17, 2010 at 3:53 AM, Bill Lorensen <<a href="mailto:bill.lorensen@gmail.com">bill.lorensen@gmail.com</a>><br>
>> wrote:<br>
>>><br>
>>> Another idea. It seems that one pipeline piece is changing the cell<br>
>>> data. Try changing the mapper's input to determine which filter is the<br>
>>> culprit.<br>
>>><br>
>>> Try<br>
>>> mapper->SetInput(cube->GetOutput());<br>
>>> first.<br>
>>><br>
>>> Do you get the proper coloring?<br>
>>><br>
>>> bill<br>
>>><br>
>>><br>
>>> On Fri, Apr 16, 2010 at 3:39 PM, Bill Lorensen <<a href="mailto:bill.lorensen@gmail.com">bill.lorensen@gmail.com</a>><br>
>>> wrote:<br>
>>> > Try,<br>
>>> > smoother->GenerateErrorScalarsOff() ;<br>
>>> ><br>
>>> > On Fri, Apr 16, 2010 at 1:30 AM, 朱文武 <<a href="mailto:cool.wenwu@gmail.com">cool.wenwu@gmail.com</a>> wrote:<br>
>>> >> Bill, thanks very much !<br>
>>> >> Here are the all related codes:<br>
>>> >> vtkSmartPointer<vtkBMPReader> m_read =<br>
>>> >> vtkSmartPointer<vtkBMPReader>::New();<br>
>>> >> m_read->SetFilePrefix("C:/Data/brain/TCVH_");//<br>
>>> >> m_read->SetFilePattern("%s%d.bmp"); //<br>
>>> >> m_read->Allow8BitBMPOn();<br>
>>> >> m_read->SetDataByteOrderToLittleEndian();<br>
>>> >> m_read->SetFileNameSliceOffset(5);//<br>
>>> >> m_read->SetFileNameSliceSpacing(1);//<br>
>>> >> m_read->SetNumberOfScalarComponents(3);//<br>
>>> >> m_read->SetDataOrigin(0.0,0.0,0.0);//<br>
>>> >> m_read->SetDataSpacing(0.167*4,0.167*4,1);//<br>
>>> >> m_read->SetDataExtent(0,299,0,345,1300,1320);//<br>
>>> >> m_read->Update();<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkDiscreteMarchingCubes> cube =<br>
>>> >> vtkSmartPointer<vtkDiscreteMarchingCubes>::New() ;<br>
>>> >> cube->SetInput((vtkDataObject*) m_read->GetOutput() );<br>
>>> >> cube->SetValue(0, 111);<br>
>>> >> cube->SetValue(1, 121);<br>
>>> >> cube->Update() ;<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkDecimatePro> deci =<br>
>>> >> vtkSmartPointer<vtkDecimatePro>::New();<br>
>>> >> deci->SetInputConnection(cube->GetOutputPort());//<br>
>>> >> deci->SetTargetReduction(0.5); //<br>
>>> >> deci->PreserveTopologyOn(); //<br>
>>> >> deci->ReleaseDataFlagOn();<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkWindowedSincPolyDataFilter> smoother=<br>
>>> >> vtkSmartPointer<vtkWindowedSincPolyDataFilter>::New();<br>
>>> >> smoother->SetInput(deci->GetOutput());<br>
>>> >> smoother->SetNumberOfIterations(30) ;<br>
>>> >> smoother->NonManifoldSmoothingOn();<br>
>>> >> smoother->NormalizeCoordinatesOn();<br>
>>> >> smoother->GenerateErrorScalarsOn() ;<br>
>>> >> smoother->Update();<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkLookupTable> colorLookupTable=<br>
>>> >> vtkSmartPointer<vtkLookupTable>::New();<br>
>>> >><br>
>>> >> colorLookupTable->SetTableRange(0, 122);<br>
>>> >> colorLookupTable->SetNumberOfTableValues(123);<br>
>>> >> colorLookupTable->Build();<br>
>>> >> for (int i =0; i < 111; i++)<br>
>>> >> {<br>
>>> >> colorLookupTable->SetTableValue(i , i/255.0, i/255.0,i/255.0);<br>
>>> >> }<br>
>>> >> colorLookupTable->SetTableValue(111, 1,0,0,1);<br>
>>> >> for (int j = 112; j <120; j++)<br>
>>> >> {<br>
>>> >> colorLookupTable->SetTableValue(j , j/255.0, j/255.0, j/255.0);<br>
>>> >><br>
>>> >> }<br>
>>> >> colorLookupTable->SetTableValue(121, 0,1,1,1);<br>
>>> >> colorLookupTable->SetTableValue(122, 0,1,1,1);<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkPolyDataNormals> triangleCellNormals =<br>
>>> >> vtkSmartPointer<vtkPolyDataNormals>::New();<br>
>>> >> triangleCellNormals->SetInput(smoother->GetOutput());<br>
>>> >> triangleCellNormals->ComputeCellNormalsOn();<br>
>>> >> triangleCellNormals->ComputePointNormalsOff();<br>
>>> >> triangleCellNormals->ConsistencyOn();<br>
>>> >> triangleCellNormals->AutoOrientNormalsOn();<br>
>>> >> triangleCellNormals->Update() ;<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkPolyDataMapper> mapper =<br>
>>> >> vtkSmartPointer<vtkPolyDataMapper>::New();<br>
>>> >> mapper->SetInput(triangleCellNormals->GetOutput()); // #this is better<br>
>>> >> for<br>
>>> >> vis<br>
>>> >> mapper->ScalarVisibilityOn() ;//#show colour<br>
>>> >> mapper->SetScalarRange(colorLookupTable->GetTableRange());<br>
>>> >> mapper->SetScalarModeToUseCellData() ; // contains the label eg. 31<br>
>>> >> //mapper->SetScalarModeToUsePointData() ;//#the smoother error relates<br>
>>> >> to<br>
>>> >> the verts<br>
>>> >> mapper->SetLookupTable(colorLookupTable);<br>
>>> >><br>
>>> >> vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();<br>
>>> >> actor->SetMapper(mapper);<br>
>>> >><br>
>>> >> Waiting for suggestion, thanks in advance !<br>
>>> >><br>
>>> >> Wenwu<br>
>>> >><br>
>>> >><br>
>>> >><br>
>>> >> On Fri, Apr 16, 2010 at 12:01 PM, Bill Lorensen<br>
>>> >> <<a href="mailto:bill.lorensen@gmail.com">bill.lorensen@gmail.com</a>><br>
>>> >> wrote:<br>
>>> >>><br>
>>> >>> The lookup table and mapper look OK to me. Can you attach the entire<br>
>>> >>> program if it is not too large?<br>
>>> >>><br>
>>> >>> Bill<br>
>>> >>><br>
>>> >>> On Thu, Apr 15, 2010 at 9:00 PM, 朱文武 <<a href="mailto:cool.wenwu@gmail.com">cool.wenwu@gmail.com</a>> wrote:<br>
>>> >>> > hi all,<br>
>>> >>> ><br>
>>> >>> > I sent the message last night! However, no one responded !<br>
>>> >>> > So, i<br>
>>> >>> > send<br>
>>> >>> > it again. Please forgive me, if it disrupts you!<br>
>>> >>> ><br>
>>> >>> > I use vtkDiscreteMarchingCubes to reconstruct anatomy structure,<br>
>>> >>> > and use<br>
>>> >>> > the<br>
>>> >>> > vtkLookupTable to map the color. Now, i design the color map as<br>
>>> >>> > follows:<br>
>>> >>> > gray value (111) to red,<br>
>>> >>> > gray value(121) to blue.<br>
>>> >>> > Other gray value I don't care.<br>
>>> >>> ><br>
>>> >>> > Also, the parameter I set in SetValue() of<br>
>>> >>> > vtkDiscreteMarchingCubes is:<br>
>>> >>> > SetValue(0, 111);<br>
>>> >>> > SetValue(1, 121);<br>
>>> >>> ><br>
>>> >>> > Then i set the lookup table as follows:<br>
>>> >>> > vtkSmartPointer<vtkLookupTable> colorLookupTable=<br>
>>> >>> > vtkSmartPointer<vtkLookupTable>::New();<br>
>>> >>> > colorLookupTable->SetTableRange(0, 122); //<br>
>>> >>> > colorLookupTable->SetNumberOfTableValues(123);<br>
>>> >>> > colorLookupTable->Build();<br>
>>> >>> ><br>
>>> >>> > for (int i =0; i < 111; i++)<br>
>>> >>> > {<br>
>>> >>> > colorLookupTable->SetTableValue(i , i/255.0, i/255.0,i/255.0);<br>
>>> >>> > // i<br>
>>> >>> > don't care this loop<br>
>>> >>> > }<br>
>>> >>> > colorLookupTable->SetTableValue(111, 1,0,0,1); // this is essential<br>
>>> >>> > for<br>
>>> >>> > me<br>
>>> >>> > for (int j = 112; j <120; j++)<br>
>>> >>> > {<br>
>>> >>> > colorLookupTable->SetTableValue(j , j/255.0, j/255.0, j/255.0);<br>
>>> >>> > // i<br>
>>> >>> > don't care this loop<br>
>>> >>> ><br>
>>> >>> > }<br>
>>> >>> > colorLookupTable->SetTableValue(121, 0,0,1,1);<br>
>>> >>> > colorLookupTable->SetTableValue(122, 0,0,1,1);<br>
>>> >>> ><br>
>>> >>> > vtkSmartPointer<vtkPolyDataMapper> mapper =<br>
>>> >>> > vtkSmartPointer<vtkPolyDataMapper>::New();<br>
>>> >>> > ...<br>
>>> >>> > mapper->ScalarVisibilityOn() ;//#show colour<br>
>>> >>> > mapper->SetScalarRange(colorLookupTable->GetTableRange());<br>
>>> >>> > mapper->SetScalarModeToUseCellData() ;<br>
>>> >>> > mapper->SetLookupTable(colorLookupTable);<br>
>>> >>> ><br>
>>> >>> > The result of construction is that two structures whose gray value<br>
>>> >>> > is<br>
>>> >>> > 111<br>
>>> >>> > and 121 were reconstructed.<br>
>>> >>> > However, the color of these actors is the same- white.<br>
>>> >>> > Ccould anyone tell me why and give some suggestions?<br>
>>> >>> ><br>
>>> >>> > Thanks<br>
>>> >>> > Wenwu<br>
>>> >>> > _______________________________________________<br>
>>> >>> > Powered by <a href="http://www.kitware.com" target="_blank">www.kitware.com</a><br>
>>> >>> ><br>
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>>> >>> ><br>
>>> >>> > Please keep messages on-topic and check the VTK FAQ at:<br>
>>> >>> > <a href="http://www.vtk.org/Wiki/VTK_FAQ" target="_blank">http://www.vtk.org/Wiki/VTK_FAQ</a><br>
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>>> >>> ><br>
>>> >>> ><br>
>>> >><br>
>>> >><br>
>>> >><br>
>>> >> --<br>
>>> >> 祝<br>
>>> >> 工作愉快，身体健康！<br>
>>> >><br>
>>> ><br>
>><br>
>><br>
>><br>
>> --<br>
><br>
><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br>祝<br>工作愉快，身体健康！<br>