View Full Version : I'm Stupid so I'm making a new thread re. Anim Cache GI

08-28-2011, 09:28 AM
I don't know when I started doing this, but some how I got it in my head that once you were done baking a scene's MC radiosity to an animated cache, that you turn Off the [ Animation ] button, save the scene, and render.

Guess what?


All this time while I'm complaining on the forum and asking WHY interp MC GI was shimmering/flickering in my last few animations using LW 9.6 and 10.1 and getting all other possible valid answers that did nothing to "fix" the problem, it was all because of turning Off that stupid little button!

Rid, you were most helpful in getting me to think, do, and test. Thank you.

SO, to summarize.

Before baking scene GI, make SURE you have created a Radiosity folder in your Content Dir.
Set the Cache File to this folder with appropriate name for the .cache file
Turn On Animation with desired Frame Step
Bake scene using desired pixel spacing, angular tolerance, and multiplier (all other params are not part of the preliminary calcs)
Leave Animation button On
For safety, turn Preprocess to Locked (even though screamnet can do nothing but this mode)
Save scene
Send to render farm

Your screamers should be saying,
Read radiosity cache: full content directory path + Radiosity\filename.cache

followed immediately by,

Recalculating radiosity samples...
Recalculating radiosity samples...
Rendering frame x, segment 1/x, pass 1/x.

If it instead says,
Read radiosity cache: full content directory path + Radiosity\filename.cache
Computing preliminary radiosity solution...

then either the cache can't be found OR, like stupid me, the [ Animation ] button in Render Globals > Global Illum tab is OFF and you WILL get flickering/shimmering GI shading in your animation.

Hey, Exception, you should ADD these specific details (re. network rendering) to your most excellent GI instruction page.


08-29-2011, 04:47 AM
Many thanks for taking the time to highlight that Animation tick-box's behaviour.

We're all susceptible to making erroneous assumptions about how various parameters work, and to then experience that forehead slapping moment when we realise, or have pointed out, our mistake!

I agree that Exception would be wise to update his outstanding GI user guide to add a comment regarding making sure the Animation box is ticked before saving a scene.

08-29-2011, 07:58 AM
At the moment tom is on a farm in the middle of France, but I am sure he will get on that in a week or so :)