PDA

View Full Version : Render Layers: Reflections


AndrewRaZ
03-02-2006, 05:52 PM
next on my list of whiny problems, is render layers. as many people know, Alias revamped the entire render layers system for version 7. what i was able to do previously was to have a background render separately of a 'foreground' which most of the time was a single character model. the reason for this was so that the background would show up as part of the reflections, but it wouldn't actually appear in the final render, so i could use the alpha channel to knock out the black background and put whatever background i wanted in.

i've read several topics related to render layers, including the maya help files (gasp!) as well as watching ashaiad's video tutorial, but to no avail. i considered rendering out a reflection pass, but decided against it because i wanted the final image out of the render, rather than compositing it later. however, i'm not opposed to doing it in separate passes, except that i can't figure out how to do that either.

any help would be appreciated

jeremybirn
03-02-2006, 07:42 PM
what i was able to do previously was to have a background render separately of a 'foreground' which most of the time was a single character model.
You still have this capability, and could even do it in all the same ways you used to, right?

the reason for this was so that the background would show up as part of the reflections, but it wouldn't actually appear in the final render, so i could use the alpha channel to knock out the black background and put whatever background i wanted in.
i've read several topics related to render layers, including the maya help files (gasp!) as well as watching ashaiad's video tutorial, but to no avail. i considered rendering out a reflection pass, but decided against it because i wanted the final image out of the render, rather than compositing it later. however, i'm not opposed to doing it in separate passes, except that i can't figure out how to do that either.
You can set whether an object has "primary visiblity" or is just "visible in reflections" as render flags in the objects attribute editor. If you need to set it for many background objects at once, you can also adjust these in the attribute spreadsheet window.

If you want to use separate layers, and the background needs primary visibility for its own render layer, then you could turn off its primary visibility as a layer override while in the foreground layer.

-jeremy

AndrewRaZ
03-03-2006, 02:00 AM
Jeremy, thank you for taking the time to reply. i have your book by the way. an excellent text.

i've done the layer rendering i'm talking about in previous versions of maya (6, and 6.5). in those versions, one would add objects to the layers, much as you do in version 7. the difference was that there was a section in the render globals menu that would control which layers would render. as long as a layer was flagged to render, it was visible to all other objects in renderable layers. now, however, it seems that maya handles rendering only on a per-layer basis, and doesn't consider things outside that layer when it computes. at least, that's the result i've been getting.

the good news is that i can set the objects to be visible to reflections in the attributes like you said, and it renders fine like that, as long as everything is in the one layer, so that's probably how i'm going to render it for now, since it does the same thing, and only renders one layer, instead of two, making it that much faster.

CGTalk Moderation
03-03-2006, 02:00 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.