Any Arnold users that can help me transition to Octane? Tweet

[noisyboyuk]

Hi

I tried a search of the forum for this but came up dry so I'm wondering if there are any Octane users here who have also come from Arnold and who know how the two compare?

I've had Octane for a while but only just found the time to start playing with it and I must say I'm loving the speed but there are a couple things I feel I'm missing. To start with I'm wondering if there is a way to drive parameters with textures in the way you can with Arnold? For example, with Arnold I often drive the weight (or mix) with a texture which runs through a float_ramp node but with Octane I don't see any inputs to connect my textures into the mix parameter. Instead it seems like I basically load a texture in and then I have a mix slider to mix it with a colour but this just seems like it's cross-fading the opacity of the colour and the texture if that makes sense rather than being able to push the colour to 100% and use the texture's luma values to control how much of that colour comes through.

I did see that there is a node called Mix Material with which I can (in a round about way) achieve the same thing but there are some things that would be quicker if I could simply drive anything with either a texture or float or whatever.

While on that subject I do also miss having a ramp float node as I use that for almost everything, using the curve a great deal to control the values of mattes.

Then there's Arnolds Curvature node which is great for creating mattes on edges or corners etc (then multiplying it with textures to create scratches or peeling paint etc.

Finally I also wondered if there was something similar to the layer_color node (which may or may not be part of the 3rd party alShaders pack?). This is like the Octane Mix Material node on steroids and allows you to stake about 10 layers and each one of those can be driven by another texture or value and also each layer has a full selection of different blending modes.

I'm sure there's a ton more stuff I'll have to work out and judging by a lot of the work I've seen out there, I expect all of this has some form of solution but for now, these are some of the things I'm really missing so if anyone has any thoughts I'd love to hear back

Thanks!

EDIT: Sorry for the double post - the page timed out and I think me refreshing the page must have created two submissions. I have deleted the duplicate thread.

[DMAEuropa]

Hi,

This is a really good topic i have been using octane for a while now and i love it i have spent the last mouth learning all about arnold and that has also grown on me.

Curvature node
Octane has a node called Dirt Map this is what we use to create warn edges and so on.

If you want to clamp textures there is a clamp texture node i dont really use this but after testing it works very much the same as the ramp float node in arnold you can drive the clamp node via textures as well but not a spline
like in arnold. or you can use the gradiant to remap the colors that works a bit like the clamp texture.

as for the layer color node well this is a great feature in arnold i am trying to figure out how to do this in octane as we only have a mix node that is some what restricted.

i would be happy to run through the basics on octane on skype as i am keen to learn more about arnold.

[noisyboyuk]

Thanks for the reply, I found it very helpful

A Skype chat sounds cool, I'll send you a message with my details!

Cheers

[noisyboyuk]

The thing I really miss (and have been trying to champion for some time now) is the ramp_float controls. In Octane the most precise way of controlling contrast and luma values is with a gradient which is honestly just bonkers to me. Having a proper spline curve with fine control not only of the shape of the curve but the granularity is a must-have when dealing with luma values in any medium. I'm really hoping this will make its way into Octane someday as it's got to be probably one of the easiest things to implement (surely it's literally just a case of using C4D's own spline UI controls and wiring them to the luma values).

The other two things I miss from Arnold are a decent layer node, which will allow plugging in more than two textures or generators at a time (with Arnold you can plug up to 10 layers at once and control their alpha weight and blending mode which really helps keep things clean).

And the biggest of all is for me is just the lack of blending modes. I use Overlay all the time in Arnold but in Octane you only have Multiply and Add but for me, Add is more useful for compositing layers than blending textures as it's a bit heavy handed.

Octane lacks a robust displacement model. The model it does have is lightning fast in contrast (as in hundreds of times faster in some cases) but this is because it is voxel based and not subdiv based. The "pro" of this is that you can have incredibly detailed displacement on nothing but a single polygon but the downside is that it only really works properly on a flat plane (for terrains and stuff) unless you have perfectly unwrapped UV's (so forget about using cube or camera projection etc). Because of this I find it better to just have both engines to do different tasks and treat them not as one being better than the other but simply different engines for different jobs.

Arnold, of course, is very easy to use but it does still have ray bounces and ray depth which is super handy especially for volume shading whereas Octane is more a case of hit render, add some samples and what you see is what you get. The plus side of this is that it's just super easy to use in that regard, but a little extra control would be nice (and I personally don't think the whole "biased vs non-biased" argument isn't that relevant anymore as most non-biased engines have at least some non-biased features).

You might also miss some of the features in the Arnold parameter tag such as turning off reflections or other passes directly on the object itself but all of that stuff can be handled in the comp - it just means that you will expend resources in rendering stuff you don't really need.

All of that said - Octane is just stupid fast in comparison for most things (unless you have a whole mess of GPU's in which case it's probably faster for all things) and the AI denoiser is really awesome.

Both engines look amazing out the box but I think that by the sounds of things you are a lot like me in that you will probably just use them both, in which case I'd learn what Octane can do and then just treat them as different tools for different jobs. One engine certainly wouldn't replace the other for me, even though I would absolutely love to not have to continue paying for two (actually 4) render engines' maintenance fees each year.

Still holding out for that one engine to rule them all

Feel free to PM me if you have any questions though dude!