Texture Atlas vs Single Texture per Models

Would it be more efficient to make a texture atlas for all my models or should i stay on a single texture per model?
Would i be able to batch all my model together if i do a texture atlas?
And if the textures atlas is the way,
How large can it be in pixels?

I think yes, using a texture atlas so all objects share a common material then batching (providing they are static) is more efficient. I guess the size of it is limited only by hardware… so if your graphics card supports 4k texture then 4096x4096 and so on. The only problem you might run into with this is if you want a texture to tile repeatedly (e.g. a brick pattern on a very large wall) - I don’t think anyone has made a shader that does this.

Yea no choice but to make an appropriate shader!

Abother option is to use large texture arrays and pass the id as part of the vertex data.
Imho one of the easiest to implement solutions if you can preload all required textures

Would i be able to batch all the node together using this technique? I don’t really understand how i could do this at the moment.

Right now i m loading all the texture in an array and i m using them separated. My problem is my building are hand made ingame, exemple if you make a foundation there would be 5 planes, resulting in 5 materials per tile, tile with adjacent tile would have 1 less planes, etc. I want to batch them to reduce the number of object in the scene and to do so i would need a single texture to represent all the possible texture for walls, floor, foundation and roof.

…or you batch by texture. That would reduce the number of objects to the number of textures at least.

You could then further reduce that by using some atlases and sharing textures… in whatever split you felt was appropriate.