Black areas on Minetest generated maps

[naulan-chrzaszcz]

For my blog, I often need to take screenshots of the worlds generated by the tool to illustrate my posts. But the main issue is that every time I generate a world, large black areas appear. Most of the time, these areas just stay there and won't disappear, even if you do something like break blocks inside the dark zone or walk over it.

[pyrollo]

Map Fixer mod could help ingame.

[pyrollo]

A proposed evolution:

• Make DEFAULTVOXEL defined (or overridable) in parameters.
• Make blocks initialized with DEFAULTVOXEL

This would allow a not so good workaround: put light=15 to default voxels.

[pyrollo]

We are correctly setting lighting_complete flags to 0. This is supposed to trigger lighting computation on loading (actually on loading any neighbor, that would be equivalent to "on loading"). See here (we produce map format version 28).

I can't figure out where these flags are actually used in Luanti.

Interesting, I tried the same map with Luanti 5.10.0 and 5.15.2.
Shadows appears on both but with 5.10.0 they immediately disappear.

Now, a big bisect have to be performed !

Other noticeable thing: dark areas are random. Running game several times on the same generated map gives different results. There must be some kind of race condition.