PDA

View Full Version : Rendering performance with GI cache & instancing



rosmo
04-05-2013, 01:28 AM
Hello!

I have fairly simple scene, with ~600 instances and few other objects. Usually I bake radiosity scene (MC) , caching enabled and preprocess set to automatic, animation checked. After baking is finished, I turn preprocess to Locked.

If I render one frame without GI cache, it takes about ~30 seconds. But with caching enabled rendering time jumps to about ~8 minutes. Event starting rendering one frame it usually takes ~40 seconds and it seems like LW doesn't do anything.

Of course this wouldn't be problem when rendering single frame on single machine, but without baking surfaces tend to flicker when GI enabled :(

Am I missing something here?

Lewis
04-05-2013, 03:02 AM
If i remember good from my previous tests and forum typing it seems that Animated caching is broken and that each next frame takes more and more to render wen "animation" baking is on :(. I stopped using it and use bruteforce GI (which is slow as hell and not applicable in some situations but i couldn't get animated GI bake to work properly at all).

SO I'm afraid there is no "easy" solution until NT fix this problem. Also i think this is reported long ago around LW 10 but if you have scene/content to reproduce it easily send it to fogbugz.

rosmo
04-05-2013, 03:54 AM
I somehow got it working for one time after switching ~every button on/off and got it render properly on farm. After that I made some modifications to scene and now LW crashes every time when trying baking GI no matter what I have enabled. Great.

MSherak
04-05-2013, 10:33 AM
I think it was fixed in 11.5.. Rendering a scene on the farm and all the nodes are rendering to the cache.. working for me..

Hieron
04-05-2013, 12:18 PM
If i remember good from my previous tests and forum typing it seems that Animated caching is broken and that each next frame takes more and more to render wen "animation" baking is on :(. I stopped using it and use bruteforce GI (which is slow as hell and not applicable in some situations but i couldn't get animated GI bake to work properly at all).

SO I'm afraid there is no "easy" solution until NT fix this problem. Also i think this is reported long ago around LW 10 but if you have scene/content to reproduce it easily send it to fogbugz.

Slowing down for consecutive frames is intended. it is keeping track of previous sample positions and will always reuse them when in sight, resulting in detail in the GI solution that would otherwise not deemed necessary. it combats splotching and can be quite useful, sometimes.

there may well be a bug but that behavior alone is not unexpected

Lewis
04-05-2013, 01:16 PM
Thing is (or at least it was) that rendering over network was much slower at each frame than on single machine (per frame) with same baked/locked GI (only when animation is on). And as rosmo experinced it's often crashing. I'd need to test agian ony some of my scenes but i know i gave up on it due so many failures/problems and figting with it in 10-11 series and somehow i doubt that crashing is/was also "intendet" behavior :(.

Normal "non-animated" bake (just camera fly through) work(ed) fine for me.