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renderbranch is looking niice !

I finally took some time to test render25 branch , and it’s looking great ..

I keep thinking , Blender might get some features with some delay (like GI) ..but when they arrive, they’re always done properly.

The environment tab where you define gi params might look simple, but still  it allows to do a ‘flavor’ of gi i always wanted to try. (and it isn’t available in Yafaray or Lux and not ‘directly’ in Vray )

As in this pic:

Direct (sun, area , meshes , env.light)

+ 1  bounce of irradiance cache (1 -3 bounces  .. to give realism and color spill)

+  additive AO (easy to control , no need of 100 bounces to fill interiors with light)  ..

… imho that’s a pretty good recipy for nice and fast renders.

Very similar to vray’s ‘winning recipy’ (IM + LC , while Blender indirect is similar to IM for 1st bounce  , then AO -as technology- it isn’t nearly as complex and versatile as light cache but can do a pretty similar job : that is quickly filling the areas of the scene that don’t receive light from direct or the x bounces of irradiance cache. Sure AO means less physical accurancy or realism ..but it’s very predictable and easy to manage )

So, all in all , i wasn’t  rushing to try render branch : i knew it would be good but it thought i’d take much more to become usable .. Well, seems to be already great (..ehr and considering it’s being used for Durian it got to be ! .eh eh)

edit : some more test along those lines, note : the above render is mostly AO with little indirect contribution hence the time (1m) more realistic tests: (still , no glossy reflections on these..)

Above: only direct + indirect 3 bounces 24 samples ..meh ..not great

Below:  with AO + indirect 1 bounce 8 samples , same time (8m) .. looking quite nice !

(you can see indirect contribution on the left)

Edit2:  another small test , “heavy indirect light” : meaning a situation where lightsource is hidden , direct and 1st bounce contribute little.

So i bumped bounces to 6 , then used AO in multiply to darken .   It works , looking good,  but not very efficient (33% size. 18 minutes (!) . 32 samples)

I really like where BI indirect is going , but now i also understand better the purpose of Vray primary and secondary gi : 1st bounce is accurate , then bounces 2-100+ are very blurred but fast.

So,  there is no secondary engine in BI ( afaik BI indirect is more like Irradiance map than light cache). But personally i always include an AO darkening pass in Vray…

Then, the most efficient method in BI seems to use an additive ao : that does both AO (which is useful anyways) and a decent substitute of secondary gi (“fill”).

Could i have used that method in this heavy “indirect” setup  ? no luck (yet) if i use 1 bounce indirect contribution is negligible (looks ok, but basically is  a direct+ao render)

with 2-3 indirect bounces  the contrast is very low , so i need AO set to multiply. (but then it’s like the pic above  : slow)

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