Generated ply has no texture (in Blender)

[chris-aeviator]

When running the full pipeline on a set of unposed images

python train.py -s /tmp/wallmart/ -o out --sfm_config unposed

that outputs ply:

`-- tetra_meshes
    `-- tetra_mesh_binary_search_7.ply

the resulting .ply file does not contain a texture, when imported via blender.

I can see that in a (now commented out) README part that the parameter export_obj has been once used, that creates textures. Am I missing something here?

I remember blender having issues with textures on ply files in the past with UV based volors, but these seem to be resolved by version 4 and other than https://projects.blender.org/blender/blender/issues/131413 I cannot find any recent issues discussing this. The solution displayed in the blender project issue however is not applicable to my Blender v 4.3.2 as it is missing these settings.

As there are textured blender screenshots in this repo I'm hoping to find a quick solution for this in here.

[chris-aeviator]

chatgpt 4o was able to help me out, here's the trick

[Mikerhinos]

Yes ply is a point cloud format so there's not really textures as there is no mesh/UVs, but each point stores color information in a
column of the data table so as you already found out you have to use a color attribute node to get it :)

[chris-aeviator]

Thanks for confirming. Do you think a short notice in the excellent readme could benefit other people facing the same issue? That has been my main motivation behind not yet closing the issue.

[Anttwo]

Hello @chris-aeviator and @Mikerhinos ,

Thanks for the nice words!

You're right, the PLY only contains vertex colors, and they need to explicitly passed as an argument to the material node.
You can do it within the shader graph, just as you did; It's also possible to use this simple setup directly in the material tab:

• Color field should be set to "Color Attribute"
• Surface can be set to "Emission". I like using Emission shader because shadows are already baked in the texture, and in practice this shader just displays the texture while removing all shading from Blender light sources.