Add custom callbacks for hovering and picking.

[AlejandroFernandezLuces]

📝 Description of the feature

Users of the library should be able to customize the behabviour of the callbacks. As of now, the default behaviour is to show the name of the MeshObject, and highlight the actor in addition to this in the case of picking.

💡 Steps for implementing the feature

Ideas for the implementation:

• Add an four implementable functions, two for hovering and two for picking, where one function will define what happens on pick and the other will define what happens when you unpick. These functions will be called in place of the add_label and remove_label functions that are currently in each callback.
• Instead of having implementable functions, accept the functions as input parameters to the PyVistaBackend. More flexible, but might be more prone to errors as well.

🔗 Useful links and references

No response

Note

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