Some hair assets are very demanding on rendering in Iray

[joecoe]

Any tips on how to handle hair assets that dramatically slow down rendering cause noise and slow down the viewport?
If I don't have a powerful GPU, is it better to avoid these types of hair altogether or use some workaround like a Scene optimizer?

 

[mickydoo]

Any tips on how to handle hair assets that dramatically slow down rendering cause noise and slow down the viewport?
If I don't have a powerful GPU, is it better to avoid these types of hair altogether or use some workaround like a Scene optimizer?

Define your not powerful GPU, it will be of more help if we know. If the viewport itself is lagging it's more likely a ram issue. Hair is hard on the system because it is a high poly count, scene optomizer only reduces the textures, I have no idea if that would do much or not. If your overall rig is weak or it's a laptop you will always have trouble with any high poly assets.

 

[Rich]

Depending on the hair product, Scene Optimizer may or may not help. In my experience, there are (at least) two categories of hair products that cause real problems, and the nature of their problems are different:

• Many of the existing G3 and G8 hair products make heavy use of transparency. Of course, that's part of how they end up looking good. This means that there transparency maps in addition to other maps, which increases the VRAM required for them. Scene Optimizer will cut down on the amount of VRAM that the hair would consume, but the multiple layers of transparency does slow down the rendering, and there isn't much you can do about that.
• Some of the newest hair products that support dForce, as well as the really new strand-based hair have a ton of geometry to them. Lots and lots of polygons. Scene Optimizer isn't going to help with this much, because it only works on the textures, not the geometry. Again, this type of hair will take some serious processing, because of all the fiddly little details of the geometry.

So, yes, if this is taxing your system, you may just have to avoid them...

 

[joecoe]

Define your not powerful GPU, it will be of more help if we know. If the viewport itself is lagging it's more likely a ram issue. Hair is hard on the system because it is a high poly count, scene optomizer only reduces the textures, I have no idea if that would do much or not. If your overall rig is weak or it's a laptop you will always have trouble with any high poly assets.

I have a laptop with i7, 16 GB RAM abd GeForce GTX 960m with 4GB.
I know it's not a pc for professional graphics work, it's just a hobby for me. And especially with Daz 4.11 and the new post denoiser I am able to make renders that I like in a reasonable time.

 

[DreamBig Games]

Some of the hair assets use Hair Cards ( less than 20.000 poly, compared with an over 500.000 some of the other hair assets have).
You can get around this with Scene Optimizer and decimator (

You must be registered to see the links

). Well worth getting it.

 

[joecoe]

Some of the hair assets use Hair Cards ( less than 20.000 poly, compared with an over 500.000 some of the other hair assets have).
You can get around this with Scene Optimizer and decimator (

You must be registered to see the links

). Well worth getting it.

You mean reducing mesh rosolution in scene optimizer? I don't know decimator yet, bu I will explore it.

 

[recreation]

You can:
Reduce the Render SubD level under Mesh Resolution in the Parameters Tab -> General (this is what scene optimizer does)
If the Resolution Level is set to High, set it to Base
For the Viewport performance set the Disply Optimisation to "Best" and Texture Resources to "Performance" under Menu -> Edit -> Preferences -> Interface
Also if the Hair uses smoothing, you can disable it until you hit the render button. This way it won't be processed until you enable it again.