VoxelToolLodTerrain.stamp_sdf() doesn't work

[Piratux]

Describe the bug As the title says, VoxelToolLodTerrain.stamp_sdf() doesn't work ~90% of the time. On other 10% of the time, I'm not getting expected mesh shape.

More precisely, by "90% of the time", I mean when I start the project, if I get unlucky (90% chance), no matter what I do, stamp_sdf() produces no result. In remaining case, when starting the project, if I get lucky (10% chance), I always see some result from stamp_sdf().

I have checked whether stamp_sdf() works in the following project but I get similar results - sometimes I see mesh stamped, sometimes nothing happens:

• https://github.com/Zylann/voxelgame/tree/master/project/smooth_terrain

I have checked whether SDF data is correct with the following, but in all cases I saw no issues:

• Printed SDF data to PNGs from _mesh_sdf.get_voxel_buffer().debug_print_sdf_y_slices(1.0).
• Added prints in internal write_box_template() function.

I see no errors in console.

To Reproduce Steps to reproduce the behavior:

1. Download minimal reproduction project.
2. Run it with Godot.
3. Follow the instructions shown in window upon running the project (see image below).
4. Notice that VoxelToolLodTerrain.stamp_sdf() doesn't work. If it does work, try closing the project and running it again (because as mentioned, in some cases it works and in some cases it doesn't).

Expected behavior See stamp_sdf() modify terrain using mesh shape.

Environment

• OS: Windows 10
• Graphics card: NVIDIA GeForce GTX 650 Ti
• Godot version: v4.2.2.rc.custom_build.474589eb8 (locally compiled 4.2 Godot with voxel module)
• Module version: Commit link: https://github.com/Zylann/godot_voxel/commit/e17cb1a5fcf6e160350c89b36278ffef35681e98
• Renderer used: Forward+

Zip with minimal reproduction project stamp_sdf_issue_mrp.zip

[Zylann]

Try with this fix 75cfda9854a2f45d00298a48ec84f7c9201ab606

[Piratux]

Alright, let me try.

[Piratux]

Okay, it seems that it works now, thanks.

I'm going to close this now.