Some bugs when use vtk in qml.(Use the official way )

Development
1

Here are some bugs when use official demo quickVtkRenderwindow with qml.

First :
In qml file , QQuickVtkRenderer cannot in Rectangle ,like this :

bug1.qml

 ...
    VTKRenderWindow {
       id: vtkwindow
       width: 400
       height: 400
     }
 
     // add one or more vtk render items
    Rectangle{
    id : parentRect
     width : 200
    height: 200
     VTKRenderItem {
       objectName: "VolumeView"
       x: 0
       y: 0
       width: 200
       height: 200
       // Provide the handle to the render window
       renderWindow: vtkwindow
     }
     }

In my test , if parentRect has width and height , the VtnRenderItem show nothing .
And if I change Rectangle to Item , that not happen.

Second :
Can not use visible to show or hide vtk either set the visible property of windows to false or the visible property of renderItem to false dynamically . It’s just to freeze the picture, not hide the picture.
like this：

bug2.qml

 ...
    Rectangle{
    id : _button
    width : 100
    height: 100 
    MouseArea{
         anchors.fill : parent
         onClicked:{
             vtkwindow.visible = !vtkwindow.visible
             _renderer.visible = !_renderer.visible
          }
    }
             
    VTKRenderWindow {
       id: vtkwindow
       width: 400
       height: 400
     }
 
     // add one or more vtk render items
    Rectangle{
    id : parentRect
    VTKRenderItem {
      id : _renderer
       objectName: "VolumeView"
       x: 0
       y: 0
       width: 200
       height: 200
       // Provide the handle to the render window
       renderWindow: vtkwindow
     }
     }


There is another bug that is not listed for the time being......
2 Likes
2

Cc: @sankhesh

(making the content different for Discourse’s spam detection)

3

@edwardAllen These are known issues that result from the way the VTK view is rendered in the QtQuick OpenGL context.

4

So If I want use vtk in Qml ,the qt::createRenderer() is a better way right ? But I had post the error about use vtk with qml by using qt::createRenderer() method , so hope you can see that issue.

5

For what it is worth, here is some of the code that we came up with. Worked really well actually.

QQuickVtkItem.cxx (16.3 KB)

QQuickVtkItem.h (3.26 KB)

1 Like
6

Thanks for sharing @Michael_Jackson. Perhaps we can use some of that logic in the existing VTK items.

7

Thanks for sharing , I will test it today . :+1: :+1: :+1:

8

Pull Request with fix
https://gitlab.kitware.com/vtk/vtk/-/merge_requests/9763