Flickering of textures and part of models when imported 3D model is big

[qarmin]

Godot version:
Godot 3.2 Beta 1
OS/device including version:
Ubuntu 19.10, both GLES 3 and GLES 2
Issue description:
When I imported to Godot model with default scale(in Godot model appears as sphere with radius +- 11000 units), then when I change camera position, model starts flickering

flickering only appears when camera is far away, when camera is close to objects, there flickering disappears

but when I change scale to 0.01, then flickering gone

I think that can be related to double precision floats, but I can be wrong.

Minimal reproduction project:
tiki_treasure.zip

[Calinou]

If you're working at a large scale, you'll want to increase the camera's Near value (both in the Camera node and the editor camera using the View menu). If it's too high, objects will be cut off when you get close to them, so you need to find a balance.

[lawnjelly]

It looks like z buffer fighting. You need to tune the near and far values of cameras you are using (both the IDE viewport and the game cameras) according to size of the world you are using (or rather your desired view distance).

This isn't really a bug per se, it's just how z buffers work. With godot (and most standard setups) you have more z precision close the camera than further away, hence less z fighting closeup.

Instead of fixed near / far, you could have a viewport camera in the IDE (or in game for that matter) that dynamically adjusts near and far planes according to the camera position / world size, but that might cause issues itself.

[aaronfranke]

This is expected, but it might be solved in the future, see the discussion in #33207. What I would love to see is multiple cameras per viewport implemented, and used in the editor, so that we can have ultra-large and small scales at the same time without flickering.

[Calinou]

I think it's mostly a documentation issue right now. We should find a documentation page where we can mention caveats related to large-scale rendering (and how to configure Godot to make it more suitable for this). See also godotengine/godot-docs#2808.

[Calinou]

This caveat is now documented in 3D rendering limitations, closing.