Using Render Layers as Passes


Is there a way to use selected layers and make Blender do the render Layers as passes
such to use in the compositing nodes?

For example
Nebula Layer
ooxoo ooooo
ooooo ooooo

Star Layer
oooox ooooo
ooooo ooooo

Selecting which corresponds to the Nebula and Star Layer to render image:
ooxox ooooo
ooooo ooooo

Would make Blender render full scene with the specific area and elements for the each render layer. Just to isolate things to passes for each render layer. I don’t think it would be a hard function to implement and can be simple button to turn this type of rendering off and on. I’m not a programmer thats why I asked.

Just a thought…


I think you can do what you want with scenes. Just think of a scene as a pass. Then in the compositor you can combine them (in the master/final scene) in any order you like to produce a final output. You can even link objects and cameras between scenes if you need synchronized elements between passes.

But Render Layers themselves are quite powerful and can do much of what you need. The reason to use another scene might be if you wanted to render some kind of pass/element at a different size or aspect ratio from the main comp then integrate that output back into the Node network to control some other part of compositing.

For instance, you could make a super wide nebula background scene with an animated Transform node to make the background pan in a much smaller final composite.

Yeah, multiple Scenes is a good way to create very disparate effects methods and combine them in the Compositor. Example: I’ve used the Main Scene for the perspective camera and model work, and an auxiliary Scene for multiplane animation using 2D imagery to create mock parallax, animation-stand style, with an orthographic camera. The blend of the two treatments of imagery was completely seamless.

I will try the method on a animation. Thanks.

Thats good but I have to try that out. I created a similiar setup using only one scene which seems to work.

This is very possible if the camera specs work for both main subject & BG. In my case I was using a short lens for the perspective work (scale emphasis) that would have made using billboards in the same Scene unwieldy, plus a small camera move that would have exposed the edges of the image planes in the BG. All that was solved by the separate Scene and ortho camera, where I could control the BG to exactly the degree necessary.

Chipmasque, how did you animate the 2 cameras to interact correctly? Use a constraint target?

The perspective camera on the model was just a slow dolly left to right to keep things from looking too static. The ortho camera on the auxiliary Scene was static, just as with a traditional animation stand, and the multiplane art (billboards with alpha) was animated to produce the mock parallax. The 2D art renders very fast, so I basically just ran out image sequences for that which I popped into the VSE, and did OpenGL frames of the model/camera move that I compo’ed in the VSE with Alpha Over – the Open GLs were PNGs done using the Premultiplied option for an alpha BG. So essentially I just eyeballed the whole thing. I’ll see if I can put one of my tests up on Vimeo or YT & embed it here.

2 of my favourite technologies, Walt Disney’s multi plane camera and space elevators!

Heh, heh ;D For a real treat, though, check out Max Fleischer’s Popeye the Sailor Meets Sinbad the Sailor (1936), which “make[s] use of the[sic] Fleischer’s Tabletop process, which used modeled sets to create 3D backgrounds for the cartoon.” --(Wikipedia, where else?). That and Popeye Meets Ali Baba’s Forty Thieves were shorts I used to hope to see every Saturday mornin’ as a kid, rich, full color and a look that knocked multiplane in a cocked hat. Disney? Meh. “The first multiplane camera, using four layers of flat artwork before a horizontal camera, was invented by former Walt Disney Studios animator/director Ub Iwerks in 1933, using parts from an old Chevrolet automobile.” [ibid] Ol’ Brer Walter was kiping ideas even back then…

I see your wiki-fu and raise you…

The most famous multiplane camera was invented by William Garity for the Walt Disney Studios to be used in the production of Snow White and the Seven Dwarfs.[3]
Disney’s multiplane camera, which used up to seven layers of artwork (painted in oils on glass) shot under a vertical and moveable camera,[3] allowed for more sophisticated uses than the Iwerks or Fleischer versions, and was used prominently in Disney films such as Pinocchio, Fantasia, Bambi, and Peter Pan.

“most famous” != “first”. Disney was a showman and used-car huckster par excellence, and way too often took credit for “borrowed” ideas. IMO.

But he made the promotional movie about it, marketing wins. Just ask Thomas Edison!