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How do we add a Volumetric Spot Light in Blender Octane 218.1 / 17.6 like we can in Octane 2018.1 Stand Alone?

It should work the same way...

Is there any specific part that you're having trouble with?

You can also take a look on this topic: viewtopic.php?f=32&t=70779

ChrisH wrote:It should work the same way...

Is there any specific part that you're having trouble with?

You can also take a look on this topic: viewtopic.php?f=32&t=70779

I think he is talking about Spectron in this case. I'm not able to run 2018 right now so I can't check.

grimm wrote:I think he is talking about Spectron in this case.

Ok, was going to say "then no", but noticed that I'd downloaded the wrong versions yesterday (and couldn't find Vectron), my answer is now is: maybe (and it should work the same way).
So far I haven't seen any good examples/guides on how to set it up (The official documentation, for SA, have no information on Vectron etc, but that's not really a shocker).

There is an example file in the topic for the release (topic: viewtopic.php?f=24&t=70809 file: download/file.php?id=73099 ).
And you could (theoretically) copy that setup in Blender. but it's quite complex (and it uses LUA scripts* etc), "Spectron" isn't really a "ready to use feature" (such as Vectron), it's something that you can do (with a less than simple setup) with Vectron.

(I tried to save the setup [also specific part of it] to LocalDB in SA and then import it in Blender, but no luck so far.)

(*I'm not even sure we can use LUA scripts in BO)

Yes I am talking about the new Spectron /Procedural Volumetric object available from the Lights menu in Octane stand alone 2018.1 (see screen shot). Both Octane stand alone and Octane Blender 2018.1 are stable releases so shouldn't they have the same features?

FYI - if an ORBX from stand alone is exported with such a light it appears fine when rendered in Octane Blender as an ORB Proxy. But I can see no way directly within Octane Blender to add this new Spectron Light object?

pegot wrote:Yes I am talking about the new Spectron /Procedural Volumetric object available from the Lights menu in Octane stand alone 2018.1 (see screen shot). Both Octane stand alone and Octane Blender 2018.1 are stable releases so shouldn't they have the same features?

I guess you don't need that complex setup after all (I totally missed that node, because I thought it was an script setup for the demo file).

The Volumetric Spotlight looks to be a bit "special", as far as Octane nodes goes.. In 2018.1 it has the node type "Unknown", in 2019.1 XB1 it is an "Built in Node graph", that (plus the script from the demo file, and some other things) leads me to think it's basically a (compiled!?) script in disguise.
Whether or not this should affect if we can use that node in BO is another question, IMHO it shouldn't...

That leads to your question about whether they should have the same features, and you would think that they should. Well at least to a certain point.
Octane uses a "global node system", where everything, including objects/meshes, is nodes and the node tree your working with is basically your whole scene/project. In Blender we (mainly) just work with nodes just for materials, this leads to some awkward ways to handle certain things, like Vectron:
In SA you basically put your Vectron node into your Render target Geometry input (maybe via a geometry group or w.e.), in BO you have to add the Vectron node in a material, use an "placeholder" object and then, in the mesh settings, select that material and then the vectron node you want to use.

As for getting the Volumetric Spotlight in BO, looking at the result in the render (and the Lua script) it actually seems like it's just setting up a couple of meshes (the barn doors, an emitter and a cone with a volumetric medium), you could easily just do that with normal objects in Blender, the downside being that it's a bit more work and you don't get an "easy" interface to control it.

ChrisH wrote:

pegot wrote:... leads me to think it's basically a (compiled!?) script in disguise.

I was starting to think the same thing and wondering if there was some code we could just plug into a script node or something?

Can the devs give some feedback on this?

This new objects is a great way to get easy volumetrics. FYI ChrisH - the barn doors feature is what interests me least in these lights and so far in my testing I have been turning them off.

Hi,

Spectron is not available in Octane for Blender yet, since the volumetric light is not available for plugins for now.

Here's my solution(s) for Volumetric spot lights in Octane Blender.
The first one (left) is my preferred way, by using an image texture for the Distribution of the Emission node. By scaling that object in (local) X+Y you can control the size of the cone (the object it self is pretty small). And then a cone with a volume.
In this case I rigged it up so you can match the size of the light circle together with the size of the cone, it's not perfect (since the relationship between the sizes isn't linear, and also depends on the distance to the surface), and it might be easier to control it separately (by turning off the Constraint on the light source).

The second one (right) is basically the same as the Volumetric Spot Light in SA (w/o the barn doors). I added a "gobo"/"hat", just to be able to control the spill.


The Second one has some problems (which it obliviously shares with the Volumetric Spot Light: See render from SA below). Firstly it creates way too much spill (IMHO), without any barn doors/flags/etc (and the barn doors limits it to a square shape, which isn't always (rarely?) desirable (from a spot light). Secondly the volume cone creates an shadow, which doesn't look natural (for most spotlights, that should be the brightest point...). If you create it yourself (aren't using the Volumetric Spot Light), you can control it by turning of Shadow visibility for that object (but that doesn't help if the cone "goes through" the surface it's shining on).
The plus side is that you get a visible light source (good for some scenes, like in the example, on the other hand you could fake that with the other method..) For the first method you have no spill. It does have the same problem where the cone creates an shadow (unless you turn of "Shadow visibility"), but since you can control the light itself so it matches the cone (and it's shadow) it isn't noticeable. The negative aspect is maybe that the light source/mesh itself is really tiny (similar to spot lights in "Blender Render"), but you can get around that by adding a bigger light/mesh only for that effect (but not a problem if the "source" isn't visible/outside of the frame).

That's just my 2 cents..

pegot wrote:How do we add a Volumetric Spot Light in Blender Octane 218.1 / 17.6 like we can in Octane 2018.1 Stand Alone?

There's a great tutorial on how to fake this (for now) with gobos and the dirt node, here:

https://youtu.be/9FplYBVKnyQ

Looks convincing. Good control and falloff. Skip to 20 (ish) minutes to see the result.