Render Elements - Max Layers

[sv]

not sure if this would be possible, but could another render element be added to the list which would be the different Max Layers.

I think this would be a really quick and easy way to split up parts of an image...

I envisaged that it could work like the VrayMaterialSelect - you could pick a layer from the scene, and this could be separated out into it's own render element.

It would save having to hide / make invisiable to camera / un-renderable ~(etc. etc. or however you would do it) different bits of the scene, that you may want to be reflected in the scene.


Would this be a good idea / possible?

[percydaman]

interesting idea. Check out RPManager. You can setup multiple passes where visible items are determined by what layer they are one. Does exactly what you want and sooo much more.

[Morbid Angel]

I dont see much benefit to this; when objects become occluded by other objects in layers, they will have to be used as holdbacks, so they will have to be included in current layer.

[sv]

I dont see much benefit to this; when objects become occluded by other objects in layers, they will have to be used as holdbacks, so they will have to be included in current layer.

You'll have to excuse my ignorance - i don't understand this.

I was merely thinking it could be a way of organising objects into layers, both for the scene and for rendered elements.
For example, we are involved with a project which is a bit of a nightmare where another company is producing one part of a scene, and we are adding other little bits in. We have to render our bits, and send them back to the client on a separate layer in a layered image. It would be useful to be able to select all of our added work, put this on a max layer, and split it up into a rendered element.

In my opinion this is a far from ideal way of working, but this is what is wanted by the client.

The way the VrayMtlSelect works is perfect and extremely useful, but i want many objects not a single material.


Percy: Many thanks, sounds about right, i'll look into it.

[joconnell]

What morbid means is that if you've got loads of different objects, some yours, some others, the other objects will still be needed to act as cut out objects for mattes. Regardless of what ends up in the final image, you still need the other objects to cut holes in your renderable objects so that it layers together correctly.

What you're talking about is a little bit like z-compositing where each object has it's z depth rendered in a seperate channel and a compositing program uses this information to determine if one object goes in front of another - kind of like a "stacking order" in the image. Sometimes you will get anti aliasing issues along the edge such as those when trying to use post depth of field.

The only way I could imagine this working is that if you have a distinct foreground, midground and background with each company working on only one so it's a really simple comp on top or behind - if you have a few different elements at different depths in the scene it's going to be a huge pain in the ass. This is why effects jobs are normally broken into shots on film jobs - it's going to take a huge effort to organise multiple places working on the same shot which isn't really worthwhile in a lot of cases...

[sv]

What morbid means is that if you've got loads of different objects, some yours, some others, the other objects will still be needed to act as cut out objects for mattes. Regardless of what ends up in the final image, you still need the other objects to cut holes in your renderable objects so that it layers together correctly.

Yes absoluetly, but i've never said hide any objects - what i meant is similar to the VrayMtlSelet where a certain object (or what i'm suggesting would be objects) could be singled out by the renderer.

For example:
(Very simple set up scene.)
Lets say we were sent a scene with three teapots in (the one in the foreground, the orange one and the blue one.) We have added the white teapot, the floor and the cylinders.

Using VrayMtlSelect you can save out the different Materials into render elements, without having to hide or apply matte materials onto any objects:

rgb:


Render Element - VrayMtlSelect - White Plastic on teapot


Render Element - VrayMtlSelect - 128 Grey on Floor & Cylinders



Suggestion: Also being able to order objects into Max Layers, then using a similar render element option to split these out of the render:
Combined Materials & Objects onto a single layer:


I'm not saying this is an absoluetly vital necessity to Vray, but i have found a use/need for it, and wonder if other people could possibly use this if it was implemented?

[MegaPixel]

Have you looked into the .PSD manager by Cebas yet? You can automate the layer creation process by tagging elements by material or geometry and then they're all automatically dumped into one photoshop file. It's fairly handy fot his kind of work and yes, sometimes I wish Vray could do it the same way.

[joconnell]

Getcha now - The wireselect option goes some of the way towards doing this so if you make your layers and then make sure each object on that layer has the same wireframe colour assigned to it you'll get a matte automatically - admittedly it's still not exactly as having it's own render with an alpha made automatically but still a handy enough way to get a matte for every part of a render in one go. RP Manager will give you a tonne of options but it'll still require each pass to be render seperately - it's not giving vray any more advanced splitting capabilities, it's more of an automation of workflow type of thing.

[sv]

make sure each object on that layer has the same wireframe colour assigned to it you'll get a matte automatically

Well that's 95% of the way there at least, and a very powerful start. Thanks john, i'll have a look into it.
One option i did look into was using the VrayObjectID to produce a matte, but it's not anti-ailised? Should i be using the coverage channel with this? I don't think i'm alone in not fully understanding how to combine all this data to get what i'm after....


Megapixel: I have heard of this, but never used it, so this sounds like a definite option for the future. thanks.

if you have a few different elements at different depths in the scene it's going to be a huge pain in the ass. This is why effects jobs are normally broken into shots on film jobs - it's going to take a huge effort to organise multiple places working on the same shot which isn't really worthwhile in a lot of cases...

I know...its a massive pain in the ass, but i can only be thankful that we are just one of the parts and we're not trying to manage the thing!

[joconnell]

Yeah that's one of the issues alright, it's not possible to have two different objects assigned to the same pixel when you think about it - the coverage channel could go some way towards helping since it'll respect the obects anti aliasing but the only problem is that I haven't found a system that can take advantage of it yet. Lets say for example a motion blurred object - if you were rendering the id channel how would you deal with all of the semi transparent levels? You'd need the harsh ID channel and then something like the coverage channel to control how the blur is fading off into the rest of the image. Personally as an after effects guy I've never used the coverage channel, it's always been with seperate matte passes and individual renders - mainly due to motion blur not being matchable between different render engines but I'm going to really look at reelsmart motion blur guided by vrays motion vectors which should hopefully allow me to blur in 2d after I've done all of my layering - it should hopefully solve some of the layering problems.

[Dynedain]

Combustion takes advantage of the coverage channel when it does operations.

[joconnell]

Seems to be about the only one that does.

[sv]

interesting to see that the caustics cast onto the grey ground material don't show up when the material is split by the VrayMtlSelect element...

Is there any reason for this?

(You can see the caustics in the top RGB image, but not in the other images)

[instinct]

This might be worse then not posting, but we sorted that issue by an in-house plugin to create mattes. Cant say any details nor will it most likely reach the public...but at least shows it's possible (HAIL DIMO! :P )

Thorsten

[sv]

This might be worse then not posting, but we sorted that issue by an in-house plugin to create mattes. Cant say any details nor will it most likely reach the public.

ha ha !

no, it's better to post, because at least it's a recognized issue?
Or is there a technical reason why Caustic's wouldn't show up?