Summarize the question: Does Open3D have a feature for selecting and annotating faces, similar to a brush tool?

### Checklist

- [X] I have searched for [similar issues](https://github.com/isl-org/Open3D/issues).
- [X] For Python issues, I have tested with the [latest development wheel](http://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](http://www.open3d.org/docs/release/) and the [latest documentation](http://www.open3d.org/docs/latest/) (for `master` branch).

### My Question

Detailed description of the problem: I want to load and display a triangle mesh model in Open3D's visualization window. Then I hope to be able to make polygon selection and clipping on the mesh mesh model to achieve the function similar to the painting brush. Is this function available?

Second question: I noticed that after adding a mesh using the add_geometry method, the shortcuts available in the draw_geometry method don't work. Is it possible to customize the shortcuts for the visualization window of the mesh added using the add_geometry method?

Here is my code and related files：
[test.txt](https://github.com/isl-org/Open3D/files/13202084/test.txt)