# How to get access to existing vtkSMRenderViewProxy?
**URL:** https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882
**Category:** Development
**Created:** [February 6, 2024, 12:28pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882 "2024-02-06T12:28:33Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@joint](https://discourse.paraview.org/u/joint)
#### Post date: [February 6, 2024, 12:28pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/1 "2024-02-06T12:28:33Z")
Hello dear developers!
Could you explain me please, how to get access to vtkSMRenderViewProxy in order to invoke points selection from a custom widget?
Best regards
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 6, 2024, 12:29pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/2 "2024-02-06T12:29:49Z")
> [@joint](#):
>
> how to get access to vtkSMRenderViewProxy
Hi,
From where ? from a pq class ?
Best,
---
### Author:  [@joint](https://discourse.paraview.org/u/joint)
#### Post date: [February 6, 2024, 12:38pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/3 "2024-02-06T12:38:19Z")
Nice to see you Mathieu,
Yes, I am trying to add a new widget, following the tutorial, it is a subclass of pqPropertyWidget following the prototype:
ClassName(vtkSMProxy \*smproxy, vtkSMProperty \*smproperty, QWidget \*parentObject=0)
I am trying to make some points of the dataset selected.
Unfortunately, if I use vtkPythonInteractiveInterpreter, something is triggered and RequestData is called in my filter, which is not desirable due to long time the computation takes.
```auto
from paraview.selection import *
SelectIDs(IDs=[0, 1], FieldType='CELL')
```
I was trying to found the way to do the same in C++, and the closest thing I found was
vtkSMRenderViewProxy::SelectSurfacePoints , but I dont know how to get access to it from the widget
If you could tell me how to make points selected by their IDs with C++ means only, I would be very happy.
I would appreciate your advice very much
Thanks for your reply!
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 6, 2024, 12:46pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/4 "2024-02-06T12:46:01Z")
from a pq class, you can access to vtkSMRenderViewProxy using `pqRenderView::getRenderViewProxy`
[https://kitware.github.io/paraview-docs/latest/cxx/classpqRenderView.html#a9ae103dbd51507809f3d37b00a2a1cf8](https://kitware.github.io/paraview-docs/latest/cxx/classpqRenderView.html#a9ae103dbd51507809f3d37b00a2a1cf8)
---
### Author:  [@joint](https://discourse.paraview.org/u/joint)
#### Post date: [February 6, 2024, 1:00pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/5 "2024-02-06T13:00:48Z")
Thank you!
Is there a class that allows to select points by ID, not by region?
---
### Author:  [@joint](https://discourse.paraview.org/u/joint)
#### Post date: [February 6, 2024, 1:07pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/6 "2024-02-06T13:07:36Z")
Mathieu, could you please clarify how to create an instance of pqRenderView from the widget?
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 6, 2024, 1:15pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/7 "2024-02-06T13:15:31Z")
> [@joint](#):
>
> how to create an instance of pqRenderView from the widget?
Usually you use an already existing view
> Is there a class that allows to select points by ID, not by region?
Then you do not want to use this API, but you want to create a SelectionSourceProxy directly.
---
### Author:  [@joint](https://discourse.paraview.org/u/joint)
#### Post date: [February 6, 2024, 2:00pm UTC](https://discourse.paraview.org/t/how-to-get-access-to-existing-vtksmrenderviewproxy/13882/8 "2024-02-06T14:00:55Z")
If I got right what you said, you referred to the vtkSMSelectionHelper
I have tried the following:
```auto
vtkSelection* sel = vtkSelection::New();
vtkNew ids;
ids->SetNumberOfComponents(1);
for (unsigned int i = 0; i < 500; i++)
{
ids->InsertNextValue(i);
}
vtkNew selectionNode;
selectionNode->SetFieldType(vtkSelectionNode::POINT);
selectionNode->SetContentType(vtkSelectionNode::INDICES);
selectionNode->SetSelectionList(ids);
sel->AddNode(selectionNode);
vtkSMProxy* selproxy = vtkSMSelectionHelper::NewSelectionSourceFromSelection(given_proxy->GetSession(), sel);
vtkClientServerStream stream;
stream << vtkClientServerStream::Invoke << VTKOBJECT(selproxy) << "AddGlobalID" << 1770 << vtkClientServerStream::End;
vtkSMSession* session = selproxy->GetSession();
session->ExecuteStream(selproxy->GetLocation(), stream, false);
```
It throws no errors, but sadly enough, it does not select any cells
Could you help me understanding what s wrong here please?
Best regards