5 float-image textures max on Cycles GPU (any workaround?)

Support Materials and Textures
1

Good morning !

I’m currently working on a character with a lots of details.
I have got on it :

  • 8 UDIM textures for the displacement map (32 bits)
  • 8 UDIM textures for the normal map (16 bits)
  • 8 UDIM textures for AO map (16 bits)
  • 8 UDIM textures for Diffuse (16 bits)

It’s working without problem on CPU.
But when i tried to render on GPU (I’ve got a titan X) only 5 random textures are rendered.
I found that the documentation says :
http://www.blender.org/manual/render/cycles/gpu_rendering.html

“CUDA:The maximum amount of individual textures is limited to 95 byte-image textures (PNG, JPEG, …) and 5 float-image textures (OpenEXR, 16 bit TIFF, …) on GTX 4xx/5xx cards, and 145 byte-image textures and 5 float-image textures on GTX6xx cards and above.”

But 5 is a ridiculous number :confused:
I know there are limitations with CUDA

But Octane Render can handle 32 float-image textures and 64 image textures.

I imagine there is no way to easily change the balance for Cycles with some codes ? :wink:

So the only solution would be to reduce all my maps to 8 bits ? :eek:

Do you know if there is a really big difference in a close-up between a 32 bits displacement map and a 8 bits ?

Thank you very much for any help :slight_smile:
Seb

2

Last I heard there were plans to change how Cycles stores textures which would remove any kind of texture count limits (so you could fit as many as you had vram for). That’s not in yet though, so no, no real workaround. Your choices are to use CPU mode, or convert to 8bit. AO and probably diffuse should be fine as 8bit. 8bit normal maps are iffy. Sometimes it’s fine, sometimes it isn’t depends on the detail range in the file. 8bit displacement is usually a really bad idea, you get stair-stepped shapes in a lot of places.

I would just use CPU, tbh. I rarely use GPU mode because of the texture limit.

3

That’s really a good info ! If I remember the next blender update will come in about one year… I imagine i just have to wait and pray :wink:

=> Thank you, you just saved me a couple hours of tests !!!

I understand better now why GPUs are not used in productions. I really think it’s the future for rendering but not yet ^^

Cheers :slight_smile: