View Full Version : Matte objects in LWSN should not load textures.

07-07-2009, 05:38 AM
Hi there.
In my never ending fight in getting people to build render farms with at least 8gb of ram, I have discovered one great way to save ram (which isn't really a discovery really, its an old trick) is to, when possible, use matte objects without texture maps on them or simply have them with black surfaces and 0% surface settings like diffuse/spec etc. Of course this means physically making matte objects and doing scenes with those loaded as replacements for everything you want as matte objects.

That can be a time consuming process though going through a master scene and replacing objects is well, stupid... Now it got me thinking... wouldn't it be very practical if at render time over LWSN when the renderer reads the scene file and sees the 'matte object flag' that it simply ignores loading the texture maps for it?

I am trying to think of any situation where this might screw something else in the scene and I can't really think of anything if the flag is set to "constant black" as apposed to "use surface settings". Since surface settings could be affected by alphas on transparent surfaces of course. maybe that can be got around, by having the object read, and parsed for transparent surfaces, and only load the texture maps on those surface to ensure its doing things right when working with matte objects that need to have "use surface settings" enabled instead of "constant black".
So I am putting this forward as a feature request.

So just to be clear, in LWSN rendering, if an object is flagged in the LW scene, on load in LWSN, screamernet bypasses loading any textures not associated on the object with a transparent surface, thus reducing image memory foot print in the rendering engine itself, while also reducing load times over the network.

I think that helps out to give LW a boost in rendering just by being smarter about what it should and shouldn't load over LWSN in certain situations like this while making the users life easier when setting shots up that require these things to be dealt with.

Make sense?
comments?? Flame throwers?


07-07-2009, 07:24 AM
Question, if you have it set as matte, does it show up in all rays etc as matte? I.e. in reflections, transparency and radiosity is it matte, or does it show the real object?

I was thinking the same thing earlier that it wasted time triangulating a subD mesh which was unseen by camera, but then I thought it has no (easy) way of determining if that mesh might be seen in some rays somewhere: It was obvious to me, because I had set everything to unseen by camera, but that's not something you will often be doing (I was rendering an in-situ HDR back plate if you wonder :D) and normally you would set the object invisible to camera, but still be casting shadows, showing in reflections etc...

07-07-2009, 10:55 AM
Good point with regards to subD but to properly produce a matte object it really should do the subdivision step otherwise in another pass the alphas won't match.