Add an option to capture scene thumbnails with fixed view

[daniel080400]

Add a setting docks/filesystem/scene_thumbnail_capture_method to toggle between FREE / FIXED thumbnail captures, FREE is the default behavior, which captures scene thumbnail by the current camera view. This PR adds a FIXED option to always capture scene thumbnails with a 3/4 fixed view (in 3d), also ensures all visual elements are within the capture.

scene_thumbnail_fixed.mp4

TODO:

• Set fixed camera zoom / fov when capturing
• Hide gizmo when capturing thumbnails
• Exclude node types that are generally not concerned in thumbnails from AABB calculation (light, particles, probes, skeletons, colliders)
• Implement FIXED thumbnail capturing for 2d scenes
• Check if performance is okay for large scenes with large number of nodes

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• Production edit: This partially addresses Improve scene thumbnails godot-proposals#7232 (3D only).

[Calinou]

This looks like a great start 🙂

However, I think this feature should always be enabled, with a way to manually override camera settings for specific scenes. This way, all team members will always see the same thumbnails when working on a project. Therefore, I don't think editor settings should be added here.

One way to implement this would be an Override Scene Thumbnail action in the Perspective menu, which would set some editor-only metadata on the scene's root node with the camera mode (perspective/orthogonal), position, rotation and FOV. (Editor-only metadata is metadata whose name starts with a _.)

There would also be a Reset Scene Thumbnail action below it, which would remove this metadata. (This action would be grayed out if the scene thumbnail hasn't been overridden yet.)

• Hide gizmo when capturing thumbnails

This should be feasible by hiding all gizmos, waiting 2 frames, taking the screenshot and restoring the previous gizmo state.

[fire]

I also think this feature should always be enabled.

[fire]

Can you run precommit?

python install pre-commit
# in godot engine directory
pre-commit run -a

Alternatively you can try copying the diff patch from the repository and git apply diff.patch manually.

[fire]

Then try godot.exe --doctool after compiling.

[daniel080400]

Continue with a better approach at #102313