There's another addon that is conflicting. I need to rewrite the map rendering at some point so that this conflict isn't possible anymore.

ok thx :), also, any idea what addon could conflict? custom hud maybe?

It would be an addon that calls render.SetLightmapTexture(). This is needed to use the LightmappedGeneric shader on custom meshes.

when it comes to tecnical things like that, i dont know much, so if i sound like a dumbass thats why, but would custom meshes include things like lfs planes and other things?

You are going to have a difficult time trying to figure out what addon is conflicting by only looking at the end result. If the addon has a legitimate use of the function, it will probably be on a mesh that does not come from a model (*.mdl file). However, I could easily see an addon using it for a stupid purpose. They could use the function as a hack to "fix" visual errors that occur from using the wrong shader. The only surefire way to find out without resorting to trial and error would be to use a search tool to search the code for use of that function. Any addon where you can find "SetLightmapTexture" somewhere in the code would be a good candidate for further investigation.

ive tried only using gmdoom and gmdoom maps, and the problem is still there. ive tried messing around with my gmod graphic settings and nothing worked. sorry to waste your time

I've determined that this is a problem with the map you are playing on. The issue is likely being caused by the brush entities in the map. If you play on gm_flatgrass, the lighting should be fine.

I ended up just applying a fix instead of rewriting the rendering. The latest version should not have the issue anymore.

so theres a new version? gotcha

hm. do i need to unsub and resub? nothing changed. and im on flatgrass.

now the shading dosnt want to make up its mind. first its fullbright, then its not. then it is again

im starting to think my pc isnt compatible with this

I only saw this issue on another map, and my change fixed it. If it's happening on gm_flatgrass, then something else must be going on, because I've never had a lighting issue on gm_flatgrass.

I know that gmod has had issues in the past where workshop items wouldn't update properly sometimes. I don't know if that is still an issue or not. If you are concerned that this might be the case, you can force steam to redownload all of your workshop items by deleting the appworkshop_4000.acf file from your <Steam Library>\steamapps\workshop folder. Make sure you close steam first.