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jrandom
07-22-2010, 12:05 PM
I've been working on my first animated sequence that involves an interior lit by luminous polygons and no lights and have discovered the horror that is animated GI.

Been through a lot of threads, read Except's radiosity tutorial... to get anything even close to a clean render for an 8 second shot at 1920x1080 requires just a silly amount of time per frame -- either interpolated MC with tiny, tiny MPR settings, animated cache, etc... or non-interpolated MR which is slower than glaciers if you're not using lights and want non-noisy surfaces.

So... I've been eyeballing KRay... it's something like $400 which I can technically afford but I had trouble getting clean renders while playing around with the demo version. (I've got no problems with diving into the manuals if that's what it takes to get clean renders, just couldn't figure it out in the few hours I poked around with it).

For all you KRay users, is it worth the cost if one is going to be doing a lot of interiors with few-to-no lights and lots of luminous polys? Is it really as fast as the sales pitch says?

Pavlov
07-22-2010, 02:09 PM
Not only it's worth, it's a must. In particular, luminous geometry is handled in a very smart way, you can chose how luminosity should behave - as direct (kinda arealight) or indirect (irradiance only, soft light), and you have plenty of tools to control every aspect of lighting.
If you plan to work on interiors, exteriors and landscaping (remember Kray has a very fast instancing system for LW) you should really get it.

Paolo

jrandom
07-22-2010, 02:31 PM
...In particular, luminous geometry is handled in a very smart way, you can chose how luminosity should behave - as direct (kinda arealight) or indirect (irradiance only, soft light)...

I just read that part of the KRay manual. I didn't get it. I read it again. I still didn't understand.

Then... *click*

... REALLY??

*pulls out wallet*

And I just bought LWCAD, too...
*sigh*

(This kinda brings Lightwave closer to the cost of the other programs it competes with. I still feel I made the right purchasing choice because I really like its approach to modeling [despite the drawbacks that lead me to LWCAD in the first place -- I can't even imagine modeling w/out a slew of easily-switchable layers now] and this fantastic yet small user community that manages to be super helpful with very, very few flamewar threads.)

Pavlov
07-22-2010, 02:38 PM
LW cad is a must as well, good choice !
Direct/indirect is not something you can understand on paper, you just have to try it and see differences. From that moment, you'll understand you *needed* that in many situations before ;)
Regarding the fact Lw (and its plugin) comes closer to other competitors, even in terms of cost: let's see it as a good thing. Correct pricing means solid development, cheap is much closer to toyland than you may think.

bye
Paolo

Intuition
07-22-2010, 02:45 PM
I haven't had much success getting flicker free animation from LW using traditional techniques.

The method I used, back when I still used LW much, was to do what I call a spinning GI trick which is not too different then the spinning spotlight trick that we used to get soft shadows from spot lights before the days of area lights.

The process involves using dithered motion blur to blend the individual GI passes together. Dithered motion blur will take each a and b pass if the GI prepass and blend them all together in the final result essentially blurring the GI. This process also blurs the AAliasing through the whole render so you can turn down the AA settings alot and still get super clean renders.

Finally the test thread we made using this method a few years ago showed people using the 0.5 multiplier which made the GI prepass resolution half of its full value which helps speed things up.

So instead of using high settings to get a clean render you use overall lower settings.

http://www.newtek.com/forums/showthread.php?t=99548&highlight=dithered+GI&page=4

This is a test scene. See if you can reverse engineer what I am doing. This might be a good method to test with native LW renderer.

jrandom
07-22-2010, 02:58 PM
LW cad is a must as well, good choice !

I absolutely love this plug-in.



Direct/indirect is not something you can understand on paper, you just have to try it and see differences.

It took me a few minutes, but I'm pretty sure I understand exactly what this does. Because the lumigons are treated as direct light sources, you won't get the noise/grain you'd get in the indirect model where you're hoping the random samples just happen to hit the lumigons by chance.

Direct == guaranteed light hits == way less noise and artifacting.

Is this right? Please say it's right because that's fantastic.



Regarding the fact Lw (and its plugin) comes closer to other competitors, even in terms of cost: let's see it as a good thing. Correct pricing means solid development, cheap is much closer to toyland than you may think.

As a software developer who can't get paid to write the stuff I want to write (I make a living writing boring telecom data translation programs instead), I fully understand this and will support companies that make good software with my wallet (within reason... I can't exactly justify buying Houdini or anything).

jrandom
07-22-2010, 03:02 PM
The method I used, back when I still used LW much, was to do what I call a spinning GI trick...

If I didn't have so many blurry reflections this might actually work, but as it stands it ballooned out my render times too much. It's a great idea though.

Pavlov
07-22-2010, 03:26 PM
Hi,


It took me a few minutes, but I'm pretty sure I understand exactly what this does. Because the lumigons are treated as direct light sources, you won't get the noise/grain you'd get in the indirect model where you're hoping the random samples just happen to hit the lumigons by chance.
Direct == guaranteed light hits == way less noise and artifacting.
Is this right? Please say it's right because that's fantastic.


Yes, but it's not just that.
Indirect has some advantages over Direct, because it's soft and extremely fast lightening. Usually, large luminous surfaces behave better in indirect mode (lumipolys at windows, skydomes) while small surfaces behave better in direct mode.

http://www.kraytracing.com/wiki/GUI_-_Quality_tab#Luminosity_model

Results are different and it's not possible to tell which is better, as said you'll find you need (and always needed) both.

Paolo

jrandom
07-22-2010, 03:33 PM
Results are different and it's not possible to tell which is better, as said you'll find you need (and always needed) both.

Yep! As soon as I saw there was an "Automatic" selection w/ threshold that I was sold. (I like being able to bounce around from automatic to manual settings depending on the scene.) Yessir, I am buying this tonight.

Edit: Correction, have purchased and downloaded and now I have to wait until I get home from work to start using it and oh boy do I hate waiting GRR RAR...

With all these new programs I'm getting it's difficult to restrain my inner child from yelling TOYS TOYS TOYS TOYS TOYS!!! while bouncing around the room like a madman.

Intuition
07-22-2010, 04:55 PM
If I didn't have so many blurry reflections this might actually work, but as it stands it ballooned out my render times too much. It's a great idea though.

Oh yeah, blurry reflections with GI equals slow with that cheat method.

Might I suggest Vray.. ;D

Seriously though, Kray is awesome but I can't say I've seen alot of animation with it to say it effectively reduces flicker without going into long rendertimes. This is only due to the fact that I haven't used it in the last year much.

jrandom
07-22-2010, 05:18 PM
Might I suggest Vray.. ;D

Hah! Oh lordy, that is one expensive renderer. They also don't have a Lightwave version and I'm not yet at the stage where I need something that fancy yet.


Seriously though, Kray is awesome but I can't say I've seen alot of animation with it to say it effectively reduces flicker without going into long rendertimes. This is only due to the fact that I haven't used it in the last year much.

It can't be any worse than the native LW renderer for the indoor-scene case and after looking over the feature set I can definitely say I need what it offers, especially since I like both blurry reflections and luminous polygons.

Lightwave still does an excellent job at outdoor/open scenes so I will most likely wind up using both renderers on a regular basis.

jrandom
07-22-2010, 05:41 PM
Oh hey, this brings up another question. When I was playing around with the KRay demo, I noticed that once I started using it I couldn't figure out how to switch back to the native LW renderer for that scene (making it more difficult to do comparisons).

Is there an easy way to switch back and forth?

geo_n
07-22-2010, 08:14 PM
I love kray. I've been bugging the developer for more features that will make it animation and composite friendly (the alpha and matt channels need to be supported).
With that said, it will be superfast for walkthrough type animation. I have not successfully rendered animated objects(deforming not rigid objects) without zero flicker though. I'm also a vray user and vray can flicker as well and the only way to get flicker free animation for me is to use irridiance cache and bruteforce passes when it comes to enclosed spaces. But it is very fast compared to lw montecarlo or kray uncached gi. Maybe the next kray engine will have faster uncached gi or something like bruteforce which is not exactly full blown montecarlo.

geo_n
07-22-2010, 08:15 PM
Oh hey, this brings up another question. When I was playing around with the KRay demo, I noticed that once I started using it I couldn't figure out how to switch back to the native LW renderer for that scene (making it more difficult to do comparisons).

Is there an easy way to switch back and forth?

render globals panel>render, below is the renderer options to switch to lw or kray.

jrandom
07-22-2010, 08:23 PM
render globals panel>render, below is the renderer options to switch to lw or kray.

Oh hey. Right there in front of me.

3dWannabe
07-22-2010, 08:34 PM
I was very interested in Kray, but they don't support exrTrader even though I've seen many forum entries requesting it.

BTW - here's a thread that might be of interest on dealing with GI and animation flicker?

http://www.newtek.com/forums/showthread.php?t=110646

jrandom
07-22-2010, 08:52 PM
BTW - here's a thread that might be of interest on dealing with GI and animation flicker?

http://www.newtek.com/forums/showthread.php?t=110646

Yep, that was one of the many threads I read through.

Currently learning how to use KRay. Still haven't figure out how to get rid of speckle/noise but it's already far better than the blotchyness I was getting with the native LW renderer.

geo_n
07-22-2010, 09:41 PM
I was very interested in Kray, but they don't support exrTrader even though I've seen many forum entries requesting it.

BTW - here's a thread that might be of interest on dealing with GI and animation flicker?

http://www.newtek.com/forums/showthread.php?t=110646

So bug the developer and jure. :D:D
I kept bugging jure and the next release might support alpha and matt finally :thumbsup:

3dWannabe
07-22-2010, 10:15 PM
So bug the developer and jure. :D:D
I kept bugging jure and the next release might support alpha and matt finally :thumbsup:

I did. I posted on the forum where others had requested exrTrader support, but didn't get any response.

http://www.kraytracing.com/joomla/forum/index.php?f=2&t=608&p=11616&hilit=exrtrader&rb_v=viewtopic#p11616

http://www.kraytracing.com/joomla/forum/index.php?f=2&t=608&p=12086&hilit=exrtrader&rb_v=viewtopic#p12086

Not sure what else I can do?

Pavlov
07-23-2010, 12:49 AM
Hi Geo-n,


With that said, it will be superfast for walkthrough type animation. I have not successfully rendered animated objects(deforming not rigid objects) without zero flicker though. I'm also a vray user and vray can flicker as well and the only way to get flicker free animation for me is to use irridiance cache and bruteforce passes when it comes to enclosed spaces. But it is very fast compared to lw montecarlo or kray uncached gi. Maybe the next kray engine will have faster uncached gi or something like bruteforce which is not exactly full blown montecarlo.

This is not clear: Kray's Lightmap + uncached FG is much faster than a full blown montecarlo solution, and it's nearly the same as Vray's LC + bruteforce, even in speed (in my experiments).
Are you referring just to animated GI, or do you find Vray's bruteforce faster than Kray's uncached even in stills ?

Paolo

geo_n
07-23-2010, 01:10 AM
Hi Geo-n,



This is not clear: Kray's Lightmap + uncached FG is much faster than a full blown montecarlo solution, and it's nearly the same as Vray's LC + bruteforce, even in speed (in my experiments).
Are you referring just to animated GI, or do you find Vray's bruteforce faster than Kray's uncached even in stills ?

Paolo

Lightmap + Uncached Gi in kray is slower than vray and produces flicker with animated objects. Kray is however faster than fullblown montecarlo in lw for enclosed spaces.
Vray Lightcache + bruteforce is not used for animation but only for walkthrough. We only use IRR anim prepass + bruteforce for animation. Super clean super fast. Any other option and even vray flickers.
For stills they're probably the same.

jrandom
07-23-2010, 02:06 AM
Kray's Lightmap + uncached FG is much faster than a full blown montecarlo solution

Do you happen to know settings for this setup that results in smoothly lit surfaces for enclosed spaces lit solely by luminous polys? I like the lack of splotchyness but I can't quite seem to get the grain/noise down to an acceptable level.

(KRay has a lot of settings and I still don't quite know how to get good results with it yet.)

Pavlov
07-23-2010, 05:15 PM
Geo-n: yes, i was speaking of stills indeed, i never needed to animate GI so i dont Know. A side note: in many cases you dont need to animate GI at all even if object move. Expecially for things like cars and people, there are few tricks to get them animated and with good shadows without animating GI at all.

Jrandom: it may depend from many factors. Please post your scene (or a more simplified one) in Kray forum so we'll give it a look. If you setup the scene properly and if you use indirect lighting, using FG 200min-600max rays and AA FSAA 4 - mitchell - rotated grid should give clean results. If there are blurre reflections you have to raise also Blur rays in Quality Tab, i.e. 200-600. But there may be other factors too.

Paolo

jrandom
07-23-2010, 05:22 PM
it may depend from many factors. Please post your scene (or a more simplified one) in Kray forum so we'll give it a look. If you setup the scene properly and if you use indirect lighting, using FG 200min-600max rays and AA FSAA 4 - mitchell - rotated grid should give clean results. If there are blurre reflections you have to raise also Blur rays in Quality Tab, i.e. 200-600. But there may be other factors too.

Ah, FSAA... I hadn't been using that, went with adaptive instead. I'm also having horrible crashing problems with KRay so after I reinstall Lightwave and try out a few more settings I'll post my scene (be kind, it's a very early work-in-progress).

I've also noticed that KRay handles transparency differently, so my Earth object is coming out all wrong. This isn't a terrible problem right now since I'll probably just render that separately using LW's native renderer and map that back onto a quad poly since it's just a distant background object.

jrandom
07-24-2010, 01:56 AM
Please post your scene (or a more simplified one) in Kray forum so we'll give it a look.

Here is the thread (http://www.kraytracing.com/joomla/forum/index.php?f=4&t=2046&rb_v=viewtopic).

Pavlov
07-24-2010, 10:43 AM
Ah, FSAA... I hadn't been using that, went with adaptive instead. I'm also having horrible crashing problems with KRay so after I reinstall Lightwave and try out a few more settings I'll post my scene (be kind, it's a very early work-in-progress).

I've also noticed that KRay handles transparency differently, so my Earth object is coming out all wrong. This isn't a terrible problem right now since I'll probably just render that separately using LW's native renderer and map that back onto a quad poly since it's just a distant background object.

My advice is to use always FSAA, dont bother with detailed settings: most of the time you'll end with worse results and/or slower times, unless you really know what you're doing. Rotated FSAA is a good compromise, just change filter (i use Mitchell 99% of the times) and grid size (i use 3 for tests, 5 for final stills, and up to 10-15 for animation).
Regarding transparecny, it can be different if you use refraction: Kray handles it correctly, since you dont need the inglorious "air" geometry to get a correct refraction on glasses. Just make a closed object, apply proper refraction and it will render correctly with nothing else.
Remember Kray may look different from LW for other reasons, i.e. translucency is computed from the whole irradiance, so Skylight or luminous geometry will cause translucency on your leaves and your cortains, while Lw calculates it just for direct lighting.

Paolo

geo_n
07-24-2010, 12:10 PM
Geo-n: yes, i was speaking of stills indeed, i never needed to animate GI so i dont Know. A side note: in many cases you dont need to animate GI at all even if object move. Expecially for things like cars and people, there are few tricks to get them animated and with good shadows without animating GI at all.


Yup there are many tricks in lw just need to set them up properly and you're right its not always needed to go the gi route.

geo_n
07-24-2010, 12:12 PM
Here is the thread (http://www.kraytracing.com/joomla/forum/index.php?f=4&t=2046&rb_v=viewtopic).

I checked your scene. Doing a test. But johny already setup a scene in kray. I'll do a lw version. Try to render johnys scene.

jrandom
07-24-2010, 03:08 PM
Regarding transparecny, it can be different if you use refraction: Kray handles it correctly, since you dont need the inglorious "air" geometry to get a correct refraction on glasses. Just make a closed object, apply proper refraction and it will render correctly with nothing else.

It was something about my node setup, apparently. I applied the transparency map in the regular surface editor and that worked.

Exception
07-24-2010, 03:57 PM
Just a question, is anything in the scene actually moving, or just the camera?
Because if it's just the camera, native LW should not be a problem so much with the GI cache. However, KRAY is better at interiors, faster and cleaner, and gives you more options for animation. Do remember though that even with KRAY actual animation and GI cache is not without drawbacks either.

jrandom
07-24-2010, 04:10 PM
Just a question, is anything in the scene actually moving, or just the camera?
Because if it's just the camera, native LW should not be a problem so much with the GI cache. However, KRAY is better at interiors, faster and cleaner, and gives you more options for animation. Do remember though that even with KRAY actual animation and GI cache is not without drawbacks either.

Yup, there's just no good animated GI solution for those of us who don't own render farms. :)

The camera is still but the shuttle is moving slowly into the hangar. This causes all sorts of subtle and pretty lighting changes on the shuttle and far end of the hangar interior which is why I can't just bake the GI once. I'm trying out some interesting settings from the KRay forums... man, this thing has a lot of settings.

I'm definitely going to render the Earth with Lightwave's native renderer and map that back on to a quad with 100% luminance, but will render the shuttle and hangar w/ KRay, methinks.

KRay is, however, crashing an awful lot (even with a fresh Lightwave reinstall) so I'm hoping to get that issue fixed or I will have wasted quite a bit of money...

Pavlov
07-24-2010, 06:33 PM
Yup there are many tricks in lw just need to set them up properly and you're right its not always needed to go the gi route.

Well, not meaning just that: i was referring to the fact you can animate objects without having to animate GI too.
So, even with frozen GI (the one you would use in walkthroughs) you can get good result animating people and cars with realistic lighting. I dont know about LW, but in Kray these tricks work well.
I never had to use animated GI... in that case i guess i'd use Fprime ;)

Paolo

Pavlov
07-24-2010, 07:05 PM
The camera is still but the shuttle is moving slowly into the hangar. This causes all sorts of subtle and pretty lighting changes on the shuttle and far end of the hangar interior which is why I can't just bake the GI once. I'm trying out some interesting settings from the KRay forums... man, this thing has a lot of settings.

Try this scene and do this:
- Load scene, set GI to Save and render just first frame. You'll save a GI file.
- Set GI to Load, point at that file and leave Allow animation On.
- Render animation keeping my parameters. If it flickers, raise Arealight min-max params, FG rays, and AA.

I didnt test it but you *should* get ship lightened by panels while it enters (BTW your ship wont get bounced light because this is frozen in GI file, but it's not an issue since lighting in interior comes from every direction). This is not an universal solution, each case has its own, but it's an example to show you what you can do in similar cases if you cant use animated GI and if you accept a little cheat, BTW.
Trick is using luminosity as Direct illumination, so they are actually Area lights. So, while global GI solution is stored and wont change, ship will get lit directly by panels while it get near and ship will cast direct shadows on interior space (actually you wont see it too much because panels are all around, i suggest to delete all panels but one to see more clearly the effect).
It's important to see what is saved with GI file and what is not. Saved infos will not change at all, while other things can change during animation. Usually this is key trick to get correct lighting on moving items without using animated GI at all - tell me if it works in this case.


KRay is, however, crashing an awful lot (even with a fresh Lightwave reinstall) so I'm hoping to get that issue fixed or I will have wasted quite a bit of money...


This may depend on something you are doing at some level, Kray is pretty stable. Check Geometry (1-2-3 pts polys, 0pts points, unify polys, delete unused UVs, repair scratched polys, triple unplanar and check if some unplanar polys remains - this means these polys are degenerated linear polys so you must delete them, and so on), check materials (delete shaders BUT kray's shaders, try to avoid some 3rd part procedurals), and such.

Paolo

jrandom
07-24-2010, 07:08 PM
Trick is using luminosity as Direct illumination, so they are actually Area lights. So, while global GI solution is stored and wont change, ship will get lit directly by panels while it get near and ship will cast direct shadows on interior space (actually you wont see it too much because panels are all around, i suggest to delete all panels but one to see more clearly the effect).

Nice! I shall have to try it out.



This may depend on something you are doing at some level, Kray is pretty stable.

The scene seems pretty clean as far as geometry and surfacing goes. I've noticed that it is far more stable rendering animations than it was -- I've mainly been getting crashes during single renders and I can deal with that. I will also try out the 64-bit version with HC to see if it's just address space I'm running out of.

Pavlov
07-24-2010, 07:16 PM
Hi,
i dont know if you fixed the object after, but this is what i found. All these issues are not Kray's (or any engine's) friends ;)

paolo

jrandom
07-24-2010, 08:25 PM
Hi,
i dont know if you fixed the object after, but this is what i found. All these issues are not Kray's (or any engine's) friends ;)

paolo

How did I miss that? I've been checking my polygon stats on a regular basis... must have been the latest edits I made to the mesh. Oh! I bet I checked the stats before I merged points (I create a lot of this in separate layers and merge them back into the main one afterward). Thank you, I will check even more frequently.

geo_n
07-25-2010, 08:54 AM
I tested the scene file.
http://www.youtube.com/watch?v=08Of_e4so3Y
render time 5min per frame in lw. I might try kray but johny already posted something there.

jrandom
07-25-2010, 10:19 AM
I tested the scene file.
http://www.youtube.com/watch?v=08Of_e4so3Y
render time 5min per frame in lw. I might try kray but johny already posted something there.

Nice! That has got to be the shiniest shuttle nose I have ever seen. :) Very nice glow BTW. Which post processing filter did you use for that?

That's static GI I take it?

geo_n
07-25-2010, 11:50 PM
Is it a shuttle? I thought like a high tech spaceship. :)
Its the standard glow in AE.
Actually no gi cache. Your bg and camera doesn't move so there's no need to render a sequence. You can also front project it to make it faster.

jrandom
07-26-2010, 01:43 AM
Is it a shuttle? I thought like a high tech spaceship. :)

It's a 30-years-in-the-future-run-down-shuttle-due-to-low-NASA-funding-landing-in-a-brand-new-space-station shuttle for a script I'm writing. I've spent weeks on the tile textures and they *still* aren't ready (hence the current solid coloring on it). I'm not really liking UV texturing at the moment. :bangwall: