Hi everyone!
Intro and Sources
So Blender 2.8 recently fixed their GLTF2 exporter, and I was finally able to bring my models into Godot 3.0. I started with a small scene and I was quite happy with the way the editor behaved, it all felt good.
Until I added a light source. You can find the full scene here if you want to check it out for yourself (link expires in 1 week):
https://we.tl/t-qulu215VNl
The scene is very simple: it's an indoor scene with some windows, some furniture and a chimney with a fireplace. No animation or dynamic objects (yet), just plain old static meshes with standard materials.
There are two light sources: pale moonlight from outside (directional light) and the fire in the chimney (fire effect is not there yet), casting some orange light into the room:
There is one GI probe which covers the entire scene. There are several problems here, and I'm not sure if they are my fault (i.e. just me being stupid and inexperienced) or if they are bugs.
Let me introduce them one by one.
Light Artifacts on the left wall
First off, there are some strange light artifacts on the left wall:
Those seem to be connected somehow with the GI Probe. They disappear if I disable the GI probe in the hierarchy. I tried different subdivisions for the probe, however this only seems to affect where the artifacts appear, but they are present in all settings I've tried. Any clues?
Moving Shadow Artifacts on the floor
The next issue are two strange shadow triangles on the floor:
The funny thing is: they neither correspond to any object which could cast that shadow. And when the camera moves, they move too:
This happens both with and without the GIProbe enabled, seems to make no difference; the Global Illumination just makes them more noticeable. I think that this might, in fact, be a bug?
The black back wall
The third problem is the back wall of the room. Yes, it is not directly lit by any light source. But we are talking about GI here and bounced lighting and what not. There's plenty of moonlight coming in through the window. Yet the back wall is almost 100% pitch black:
... which is a stark contrast, especially noticeable next to the chimney:
The chimney base seems to be hardly affected by shadows at all, whereas the back wall seems to absorb them. Any ideas on why this might happen? I think my materials might be to blame but I can't figure it out...
System Info
I'm running Godot 3.1.1 (Mono Edition) under Windows 10 64bit on a Nvidia Geforce 980ti (latest drivers), an i7-5820k CPU and 32GB of RAM.
Conclusion
Any hints on any of the aforementioned problems would be much appreciated. Feel free to download the scene and run some tests of your own. Like I said, this is my first lit 3D scene in Godot ever, after watching a couple of tutorials - so maybe in many cases I'm the one to blame. But I'm trying to learn the ropes, so all helpful comments would be highly appreciated :)
