VOXEDIT: Can't get vertex colors working on UE5

[jerobarraco]

i've exported some gltf assets into ue5 and i can't get the colors to show.

In the unreal mesh viewer the vertex colors shows as white. and using the same material i used for other gltfs it also shows as white.

apparently the colors are being exported.

is there any hindsight i can get from the format and values of these colors?

[mgerhardy]

does it work when you export with uv map and textures?

[mgerhardy]

also, do you need animations or something other more advanced, otherwise you can also try to import obj. just to see if vertex colors are working at all as they should in ue5. I don't have the ue5 editor running atm - I will compile it asap and try to be of better help here.

[jerobarraco]

I don't need animations for now so i will try objs. I will try better tomorrow.

does it work when you export with uv map and textures?

i haven't tried. but i also want to stay away from textures so it's not a solution for me. but i will try it anyway to narrow down the issue.

I will compile it asap and try to be of better help here.

I truly appreciate it, you might not need to compile the engine. just download the binary version with the epic games lancher, or if you use linux there's the EpicAssetsManager https://flathub.org/apps/io.github.achetagames.epic_asset_manager

[mgerhardy]

It's 21GB - and I don't have that much free space on my hard drive to install this atm.

[mgerhardy]

https://www.reddit.com/r/unrealengine/comments/eupiv5/vertex_colors_not_importing_from_blender/

Worth noting; Unreal import defaults to Ignoring vertex colors when reimporting models. It’s important to select ‘Replace’ if you’re reimporting, to prevent your models from losing data in the process. It’s in General Import Settings somewhere

[jerobarraco]

I've already checked that. thanks. :) but still not importing them. My assumption is that is something to do with the range or the format (eg using ints instead of floats or something like that). i also tried converting to and from srgb.

[jerobarraco]

btw, if you want to download a smaller version in the epic installer when installer if you click Options when selecting the folder you can remove a bunch of unnecessary stuff. (all of it).

[jerobarraco]

i can import obj assets into ue but the colors still doesn't work.

[mgerhardy]

vertex colors for obj is an "extension" (or abuse of the standard) - looks like unreal doesn't support it.

you could still export the colors as png file - it's just about 256 rgba colors - you can even put them into your unreal code and just use the uv data to colorize the mesh.

[jerobarraco]

Thanks, i know, but what i'm trying to avoid is sampling the texture, also that would mean i have to use uvs. and possibly its going to be different uvs for different models. i work with several different files. ive noticed that when exporting using textures vengi only exports the used colors, and since those differ from model to model i would need to set up a material for each, which im trying to avoid.

i tried several things but still this doesn't work. vertex colors on ue do work. when i use goxel for example they work correctly. i have reasons to believe that voxedit is not exporting the colors. if i export a gltf using vertex colors, but with uv disabled test vengigltf.gltf.txt , then load the same gltf to vengi, it doesn't display any color everything is white. so not even vengi can load it.

this si the sample gnome, exported using one of the last appimage nightly. "voxedit-1420360" test vengigltf.gltf.txt

[mgerhardy]

If it is float color related - i might have a compatibility fix in latest master.

The cvar voxformat_colorasfloat can be set to false to use bytes for the color.

vengi-voxconvert --input input.vox --output output.gltf -set voxformat_colorasfloat false

for voxedit the option is in the file dialog

[mgerhardy]

Please let me know whether the latest changes regarding the color type fixes the issue for unreal being able to import the colors properly.

[mgerhardy]

Closing the ticket for now - I have no way to validate the fix. If it's still an issue, please reopen the ticket.

[jerobarraco]

thanks, i could not confirm this working yet since i cant import the mesh. https://github.com/mgerhardy/vengi/issues/295#issuecomment-1672441458 i will open a new ticket for that when i have time.