# get color array from PolyDataFilter
**URL:** https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755
**Category:** Support
**Created:** [March 4, 2020, 10:12pm UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755 "2020-03-04T22:12:59Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@ShaneKirkbride](https://discourse.vtk.org/u/ShaneKirkbride)
#### Post date: [March 4, 2020, 10:12pm UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/1 "2020-03-04T22:12:59Z")
I’m trying to get an array of colors and their corresponding vertices from a polyData distance filter similiar to this: [https://lorensen.github.io/VTKExamples/site/Cxx/PolyData/DistancePolyDataFilter/](https://lorensen.github.io/VTKExamples/site/Cxx/PolyData/DistancePolyDataFilter/)
I saw this post but there is no answer.
> [@Getting color codes of the points](https://discourse.vtk.org/t/getting-color-codes-of-the-points/809):
>
> Hello, I used streamtracer and happily got my streamline(points). I color them with velocity magnitudes. I am using an external viewer, therefore (in order not to calculate all the look up table data, velocities and more) I want to get the color responding these points. Anyone has an experience with it ? Best regards,
Is there any way to access this data?
Thanks
~Shane
---
### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [March 5, 2020, 2:15am UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/2 "2020-03-05T02:15:38Z")
Please precise your question.
---
### Author:  [@ShaneKirkbride](https://discourse.vtk.org/u/ShaneKirkbride)
#### Post date: [March 5, 2020, 4:18am UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/3 "2020-03-05T04:18:34Z")
Hi @mwestphal,
I’m still trying to wrap my head completely around VTK so thank you so much for your help!
If I have a DistacePolyDataFilter like this:
```
vtkSmartPointer distanceFilter = vtkSmartPointer::New();
distanceFilter->SetInputConnection( 0, clean1->GetOutputPort() );
distanceFilter->SetInputConnection( 1, clean2->GetOutputPort() );
distanceFilter->Update();
```
I can get the vertex data and corresponding faces like this:
```
auto distanceFilterMesh = distanceFilter->GetOutput();
vtkSmartPointer points1 = distanceFilterMesh->GetPoints();;
vtkSmartPointer dataArray1 = points1->GetData();
vtkSmartPointer faceIndex = vtkSmartPointer::New();
distanceFilterMesh->GetCellPoints(0, faceIndex);
double vertexArray[3];
auto vertexIndex = faceIndex->GetId(0);
vertexArray[0] = dataArray1->GetComponent(vertexIndex, 0);
vertexArray[1] = dataArray1->GetComponent(vertexIndex, 1);
vertexArray[2] = dataArray1->GetComponent(vertexIndex, 2);
```
How do I get the distances that the distance filter calculated? I need the distance values. I’m sure there’s a way to do this but i’m maybe overlooking the technique.
Thanks!
---
### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [March 5, 2020, 7:28am UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/4 "2020-03-05T07:28:39Z")
`distanceFilterMesh->GetPointData()->GetArray("Distance");`
In doubt, do not hesitate to use the Print method to get info about a dataset.
---
### Author:  [@ShaneKirkbride](https://discourse.vtk.org/u/ShaneKirkbride)
#### Post date: [March 5, 2020, 1:47pm UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/5 "2020-03-05T13:47:37Z")
@mwestphal thanks for you help! How do I use the Print method? I’m sure there’s probably some example documentation I could read?
Specifically about the DistancePolyDataFilter and from the example provided:
I do this to get the polyData information:
```
vtkSmartPointer distanceFilter = vtkSmartPointer::New();
distanceFilter->SetInputConnection( 0, clean1->GetOutputPort() );
distanceFilter->SetInputConnection( 1, clean2->GetOutputPort() );
distanceFilter->Update();
auto distanceFilterMesh = distanceFilter->GetOutput();
```
Then if I want to look at the distance and corresponding vertices is this the correct way:
```
vtkSmartPointer points1 = distanceFilterMesh->GetPoints();;
vtkSmartPointer dataArray1 = points1->GetData();
vtkSmartPointer faceIndex = vtkSmartPointer::New();
auto distances = distanceFilterMesh->GetPointData()->GetArray("Distance");
distanceFilterMesh->GetCellPoints(0, faceIndex);
double vertexArray[3]; double distanceArray[3];
auto vertexIndex0 = faceIndex->GetId(0);
auto vertexIndex1 = faceIndex->GetId(1);
distanceArray[0] = distances->GetComponent(vertexIndex0, 0);
distanceArray[1] = distances->GetComponent(vertexIndex0, 1);
distanceArray[2] = distances->GetComponent(vertexIndex0, 2);
vertexArray[0] = dataArray1->GetComponent(vertexIndex0, 0);
vertexArray[1] = dataArray1->GetComponent(vertexIndex0, 1);
vertexArray[2] = dataArray1->GetComponent(vertexIndex0, 2);
```
Where `distanceArray[0]` is the distance `vertexArray[0]` moved?
what is the relationship between the vertex in input1 and the vertex in input2 in the example to the vertexArray?
thanks again! this is a great framework and I’m glad I found it…
~Shane
---
### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [March 5, 2020, 2:47pm UTC](https://discourse.vtk.org/t/get-color-array-from-polydatafilter/2755/6 "2020-03-05T14:47:10Z")
[https://vtk.org/doc/nightly/html/classvtkObjectBase.html#aedadf6378465fd81c2592ef64262e2a5](https://vtk.org/doc/nightly/html/classvtkObjectBase.html#aedadf6378465fd81c2592ef64262e2a5)