Hello,

Is your feature request related to a problem? Please describe.
I would like to visualize a sphere in a point cloud similar to the spheres in the interactive visualization. But I would like to be able to move the sphere by mouse or keyboard interaction.

Describe the solution you'd like
I would like to visualize a point cloud together with a sphere. The sphere should be small and located in the middle of the point cloud. Then I would like to be able to move the sphere to a different place with different coordinates using shift+mouse dragging or the arrow keys on my keyboard.

Describe alternatives you've considered
I saw that get_picked_points() or pick_points() prints the position of the sphere where I clicked. So maybe it is possible to change the x-coordinate of the sphere position by plus 1 pressing the right arrow key and -1 by pressing the left arrow key. And the same for y-coordinate by pressing the up arrow key (+1) or down arrow key (-1).
Or to drag the sphere with the shift + left mouse click and as soon as the shift + left mouse click is released the coordinates of the sphere are set.

Additional context
I would like to use these keys:

And I would like to manipulate these coordinates:
[Open3D INFO] Picked point 444 (0.26, 0.48, -1.1) to add in queue.
Maybe it is already possible but I can not find a solution in the documentation.

Thank you in advance.