BakedLightmap crashes when baking in a large scene with hundreds of 3D objects

[sanyi12]

Godot version

3.4.4 stable

System information

Windows 10 GLES3 Nvidia version 512.95

Issue description

Baking lightmaps crashes Godot.
The scene has 4 omnilights and hundreds of 3d objects from a single GLTF file. BakedLightmap node is default except the quality which was set to low to speed up the baking time.

Steps to reproduce

This is what the console says before crashing:

Godot Engine v3.4.4.stable.official.419e713a2 - https://godotengine.org
OpenGL ES 3.0 Renderer: NVIDIA GeForce RTX 3070 Laptop GPU/PCIe/SSE2
OpenGL ES Batching: ON

ERROR: FATAL: Index p_index = 5 is out of bounds (count = 4).
   at: operator[] (./core/local_vector.h:162)
ERROR:ERROR: FATAL: Index p_index = 5 is out of bounds (count = 4).
 FATAL: Index p_index = 5 is out of bounds (count = 4).
   at: ERROR:   at: operator[] (./core/local_vector.h:162)
 FATAL: Index p_index = 5 is out of bounds (count = 4).
operator[] (./core/local_vector.h:162)
   at: operator[] (./core/local_vector.h:162)

Minimal reproduction project

Sadly the project has more than 4GBs.

[Calinou]

3.3.4 stable

Godot 3.3.x is not supported for bug fixes anymore, so please upgrade to 3.4.4 and check if the issue still occurs there.

Also, I'd try 3.5.rc3 as it supports multiple images in atlases when baking lightmaps. (Make backups of your project files before upgrading!)

[sanyi12]

sorry my bad - I am using 3.4.4 I edited the initial issue.
I tried 3.5 and crashes as well. Because this is very strange I managed to put the gltf file online so you guys can take a look at it.
(please use it for testing purposes only)
https://we.tl/t-NzixzwWvzE

[sanyi12]

I also tested this in G4 and crashes. I do need to test it more as I am not sure on the testing method.

[Calinou]

I also tested this in G4 and crashes. I do need to test it more as I am not sure on the testing method.

On Godot 4, this is likely the same cause as #45296.

On both Godot 3 and 4, you probably need to increase the lightmap's texel size to reduce the generated texture size. This will also lead to smaller file sizes. The default value of 0.1 in Godot 3.x and 0.2 in Godot 4.0 is tuned for small-scale levels, not massive open worlds. In large levels, you probably want to use a value between 0.5 and 2.0 (if not more). To do so, select your glTF scenes in the FileSystem dock, go to the Import dock, increase Lightmap Texel Size, click Reimport and bake lightmaps again.

[Calinou]

• Duplicate of BakedLightmap CPU lightmapper crashes on large scenes #45296 (same cause).