How expensive is the World Aligned Texture node?

Hi guys,

I want to use the world space texture node but keep hearing it’s expensive but nobody seems to say just how expensive it is. My set up is as follows.

I have a cathedral built out of modular parts, There are separate textures for one of the walls (a piece of art) and the ceilings, pews, Windows and floor. The walls and various levels however are modular and repeat so using the world aligned texture keeps everything nicely tiled and seamless.

The texture for the walls itself is made up of 3 diffuse textures, a damage texture and 4 masks to create variation in the tiling. The platform i’m targeting is HTC’s Vive.

So my questions are…

  1. Is the World aligned Texture node so expensive as to make its use pointless?
  2. Does having the same texture applied to many modular pieces slow things down?
  3. should I combine the modular assets in to one static mesh to improve performance?

I really want to use this node as the size of the building makes standard UV mapping impractical due to the size of texture resolution, tiling and seams.

Thanks for any help you can offer.

D

  1. No
  2. The opposite in fact, re-using the same texture saves on memory and storage
  3. It depends on what you are using it for. In many cases, seperating the mesh into modular chunks would be the most optimal solution because then they occlusion culling will remove non-visible elements from being drawn. It also works better with lightmass as unreal handles lots of smaller meshes better than one giant one.

However, it’s probably not the best practice to use world aligned node out of laziness, it has appropriate use cases, but in your case regular texturing should be fine.

I would Unwrap the meshes normally. Then you can apply tiling textures to large flat surfaces. They do not need to be world aligned to be seamless. This is how most games handle large flat surfaces.

  1. It is. The way you intend to use it is not justifying its cost. In regards to how expensive, nobody will tell you. Consider it being roughly 3.5x more expensive, than a simple texture.
  2. Not the texture, but the fact that you have too many individual meshes slows everything down.
  3. Situationally, as much as practicable, you should combine number of small modular pieces into larger assets.

I think the new experimental feature in 4.19 called Proxy LoD will benefit you. You can select a number of pieces and group them as a LoD n and the mesh, texture and materials will be combined so in the end it is just one draw call for that LoD. It requires a good scene experimentation and adjustments to make it perfect.

Thanks for the help guys,

I have the Assets unwrapped already so the UV’s are not the problem.The issue I have is that with the same texture applied to each of the modular assets the repeating pattern was becoming very obvious. The other issue I was having is that when I got close to an object in VR the material would become very blurred, even with High Res textures! The only way around this was to further tile the texture which then added to the repeating pattern problem.
So,I now have the world aligned texture over the entire static mesh/es and it has dealt with the tiling and resolution issue. but am I now just creating more problems for myself further down the line?
I’m currently getting the golden 90fps but am worried I’m going to run in to problems later.

Finally, I can fairly easily drag these Assets in to substance and add a quick tri-planar projected texture there. the issue though is that to get the resolution to an acceptable level I’m probably looking at 5 or 6 - 4K textures. At what point does the cost of using multiple high res textures outweigh the use of the world aligned node?

Thanks so much for your replies, the UE community being awesome as always!

Dave

Ps. theres a couple of screens below so you can see what I’m “Trying” to do!

For those large areas you will indeed have repetition pattern issues. Usually people add to the material something to break the repetition look. The best example that comes to my mind which is acomplished with maestry is the grass material inside the starter pack. If you quickly assemble a material with just the texture it is awful, but the trick there is to change color using a noise texture. Other artists also do vertex painting to add noise on top of the most obvious repetition spots. But in your case, you would prefere a procedural way ondoing it, like the ones in this stream:

https://forums.unrealengine.com/unreal-engine/events/108596-training-livestream-creating-semi-procedural-materials-feb-7th-live-from-epic-hq

or use some of its techniques mixed with something else.

Thanks you for that, il take a look at this stream and hopefully find a more lightweight way to produce matts!