A problem of Sprite3d disappearing

[jdusart]

Godot version

3.3.3.stable

System information

Ubuntu, Mesa Intel® Xe Graphics (TGL GT2), GLES3

Issue description

I have a small scene with just a character (a KinematicBody with a Sprite3d and a Camera attached) and a plane (a MeshInstance) that acts as floor. When I move my character away, it will disappear if both the transparent option of the Sprite3d and the alpha channel of the material of the plane are active.

Steps to reproduce

I have upload a minimal project with the problematic setting. You can move the character with the up key.
On my computer:

• if the sprite is transparent and the alpha channel of the material of the plane has an input then after a bit of movement the character disappears
• if the sprite is not transparent or the alpha channel of the material of the plane has no input then the character does not disappear

Minimal reproduction project

MinBug.zip

[Calinou]

This is a known limitation of alpha transparency sorting. Sorting has been improved in 3.4 beta 4, but we can't guarantee that it will work in all situations (as in other game engines).

Use alpha scissor or the material Render Priority property to alleviate sorting issues.