Building irr and lc maps simultaneously?

[Austin]

I have a large scene that we're about to start rendering. The scene is static with one animated character, and we're planning on rendering the bg and the character in separate passes and then compositing in post so we can use saved irr maps.

When I build the irr maps I'm going to be rendering the scene from multiple angles using add to current map. But what about LC? It has a fly-through mode, but that works off the current timeline. If I change my timeline to 1 frame and render out 20 frames, will it combine the lc map for all of these? And can I do this at the same time as my irr maps, or does lc have to be primary and secondary when making lc maps?

[powerandrubber]

Short answer is yes. LC is calculated for the entire animation when flythrough mode is checked. After the first frame only imap is calculated from then on, but LC (which is already calculated after the first frame) is stored with the imap. When rendering use your saved imap and set secondary GI to none.

In other words LC does not work like imap with the incr add to current map thing, it is calculated for the entire animation at once.

[Austin]

Thanks for the quick response. LC is calculated for the entire animation... But I'm not rendering an animation just yet, right now my objective is to build complete irradiance maps so that we can then render from any angle or position and not have to calculate gi.

[Austin]

I did some tests and found that changing the timeline to 1 frame and calculating gi from several angles in the scene (with irmap - add to current map / lc - fly-through) combined all irradiance information into the .vrmap, just as it would in an animation.

[DaForce]

If you use IR and LC on single frame it will still dump all the info into the .vrmap.

Like there is no point using LC flythru for only one frame. You may as well put it on single and then just do it that way.
The only difference between single and flythrough is that with flythrough it calcs for the whole timeframe. Everything else is the same, like combining the GI info into the saved IR map.
Basically as long as you use IR and LC all the LC info will be stored with your saved IR map.
So each time you render from diffferent angles it will be all added into the IR map. no need to use flythrought for what your doing (as far as i can tell)

[Austin]

Oh. It was my understanding that in single frame mode, when rendering the second frame (not animation, just picking another angle and rendering) the lc data would be lost if I hadn't saved the first map.

I guess I was making a big deal over nothing

[DaForce]

pretty much

So as long as you save the IR map then the LC data is never lost because its combined into the IR map when its saved.

So you can then later just load up the IR map and set secondary bounces to none and your render will be the same.