Get Cellid in dash-vtk picker callback

Dash Python
1

Hello,
how I can get the selected Cell id within a callback in the vtk-view?

Thank you

2

Hi @hello12 welcome to the forums.

VTK related questions are quite infrequent. Could you add a MRE?

3

Hello,
could you please tell me what a MRE is?

4

Sure:

5

Ok I provided an example. I pollute the vtk-view with a lot of GeometryRepresentations each with low number of points.
When I click one of the representations, I would like to know the Cell Id as it is also done with the CellPicker in pure VTK. How do I get this information?

If I have access to the renderer and/or interactor of vtk, I could implement the CellPicker by my own. I just dont know how to access or to retrieve the cell id.

Somebody knows how?

import json

from dash import Dash, html, Input, Output
import dash_vtk

view = dash_vtk.View(
    id="click-info-view",
    pickingModes=["click"],
    children=[
        *list_of_vtkGeometryRepresentations
    ],
)

# Dash setup
app = Dash(__name__)
server = app.server

app.layout = html.Div([
    html.Div(view, style={"width": "100%", "height": "300px"}),
    html.B("Output of clickInfo (try clicking on the object above):"),
    html.Pre(
        id="click-info-output",
        style={'overflowX': 'scroll'}
    )
])


@app.callback(
    Output('click-info-output', 'children'),
    Input('click-info-view', 'clickInfo')
)
def display_clicked_content(click_info):
    # TODO: HERE I NEED THE CELL ID OR ACCESS TO THE RENDERER/INTERACTOR/PICKER OF VTK
    return json.dumps(click_info, indent=2)


if __name__ == "__main__":
    app.run_server(debug=True)