How do you make new, Iray-friendly textures for older items?

Llynara

How do I go about creating a new texture for an existing item (ie the Morphing Fantasy Dress) that is Iray friendly? I'm not looking to reshade it with existing Iray shaders, since they don't look that great on the MFD. I'm interested in how one makes the texture to show up well in Iray. I'd love to also take some existing older textures and update them for Iray. Throwing Uber on them doesn't always do the job.

Please excuse my ignorance for asking, I have next to no knowledge on this but am willing to try. If anyone could point me in the right direction I'd appreciate it. Searches aren't bringing up what I'm looking for. 

Llynara

I found a good tutorial for making MFD textures on Chohole's site.

Here's what I'm wondering:

• How do you make sure they will show up well in Iray? (some stuff still looks awful even with Uber on it + tweaking)
• Do the image maps need to be a certain size to look good? 

Maybe they're dumb questions, but I hate to go through all the trouble and then it not even look right in that engine. Just trying to learn and get better.

EDIT: I did find this interesting and scary looking thread. Guess I'll plunge in there and see if I can make sense of it.

Tobor

The generic Uber shader applies "normal" presets to all the Iray channels, but they may not be ideal for everything. It tends to impart a little too much glossiness for some things, for example.

Depending on the type of real-world material type you're wanting to replicate, you might try (ctrl-double-click) on some of the other Iray presets to get a better starting point. For example, on fabrics that don't impart any sheen you can try starting off with the matte rubber shader. 

Invariably you want the physical texture of the fabric to maintain a proper balance, which means fiddling with the bump, displacement, and (as necessary) normal channels. The defaults from 3DL to Iray can be either too strong or too weak. The only thing you can do is experiment. Unless you have a fairly fast system, it may be better to load only the clothing, without a character (and certainly not a character with 4K resolution textures, hair, and so on). If your machine is constrained for speed, use the Aux Viewport in a small window, and select the NVIDIA IRAY texturing option. 

The underlying Color (texture) map doesn't matter much in the success or failure of an Iray shader. The map is just a premade image for the various material zones. You can likely keep the same Color maps you have now, and you probably don't need to create your own unless you want something totally new. What you may need to do, depending on the result you're after, is modify and/or create your own specular, glossy, top coat, and other maps in order to produce that extra bit of realism. This isn't necessary difficult, but each type of map has its own requirements.

Llynara

Thanks for the information, Tobor. I thought I was missing some magical piece of information, but sounds like I was on the right track. I've been in those settings a lot lately as I've been reshading old skins for Iray. Glad to hear the process is pretty much the same- Uber + experimentation! LOL

Toonces

I recommend 'Convert It! by vyktohria' on rendo. It's like OOT and UHT hair shaders but for clothing and other materials (metal, rubber, etc.). Best part is that it still makes use of the original textures. Even better, if your item has a bump map, it can tweak the bump for some really nice iray conversions.

SixDs

"some stuff still looks awful even with Uber on it + tweaking"

Hi, Lynara. I wonder if you could be a little more specific about what you are expecting versus what you are getting. "Awful" is a pretty subjective thing. Are the colours themselves not what you are expecting? Are the fine details not showing? Are the types of surfaces not rendering accurately (i.e. satin, versus silk versus versus cotton, etc.)? Are you looking for details such as fabric weave?

Perhaps answering these might lead to isolating the problem.