Can't seem to get it right..

[Jeroen]

Incited by some thread on the NT forums, I tried again to render foliage in Kray. I do like the prospect of using its nicer translucency and hailed superspeed. I always need animation, camera animation that is, so not too much jitter between frames would be nice and some caching to reduce rendertimes.

To compare a bit, I set up a test scene. Really simple scene, no instances (yet) and all textures stripped out.

LW native first:
Baking GI took about 25 seconds. Then rendered it which took 5.6 to 10 seconds per frame (4 AA). Result attached. This is what I would normally use, if not using a tree with GI baked into verts or UV map. It does require a bit of odd "trick" on the global GI settings but ok. Stable, contact shadows and cached (15 MB here). Added a comparison to Fprime which it matches quite well. (sort of consider Fprime "perfect", no transl ofc)

Then I really tried in Kray, but just cannot get anywhere near such a thing. Not even close. Spent quite some hours on it now and put the scene on: (was big due to tree)
http://rapidshare.com/files/403657363/Tree.zip.html (only 10 downloads.. )

(which is also used the the LW test). Tried irradiance cache on all, brute forcing the leaves and branches (don't like the jitter due to that) etc etc. The translucency sure is nice though.

This is not meant as a LW vs Kray battle, I'm sincerely trying to understand what I am doing wrong since it must be faster judging by:
"If you set properly these things, there's no quality/speed comparison with anything else in LW arena"
"because Kray was so much faster"

I hope someone could give me some pointers here. Im eager to learn and tried the suggested things in that thread.

ps: instances go at about the same speed so can be ignored here for now.

[nico]

have you use for foliage kray surface shader??

see it:
http://www.kraytracing.com/wiki/Kray_pl ... ce_Shaders


read this discussion:

http://www.kraytracing.com/joomla/forum ... =viewtopic

yesterday i've rendered an exterior with 25 trees + 12 plants - 1600*1200 px in 2.32min
i love kray

[Janusz Biela]

1/ please don`t compare LW and Kray, becouse this is immposible. Yours scene is very basic and synthetic. I know LW engine has good contact shadow but LW engine render look as "raytracing" , renders are poor with colours and good GI mix colours....
Problem is from bounce light . In Kray You have full recurse (maximum is 1000) G. work now on new Engine for Kray with better detection GI, but this does`t mean Kray has slow or bad engine. Kray Is incredibly fast but need learn knowledge about new features., this is not FPrime engine....ONE BUTTON....Kray shows POWER in complex scenes, big, difficult.
2/ try make more complex scene with smooth shadow Sun, reflection on leafs (no specular!) bump map, and You will see how fast is Kray
3/this is render directly from Kray (no PS) with poor GI for prev., one miliard poly, 2 milions photons shot, 6 Giga RAM ,all surfaces has reflection and blur, recurse10 (REAL 10 bounce light), Physky, time 10 min.....and beautiful tonemaping
4/ try use on leafs shader Precompute filtered+raytrace direct
or Photon mapping without CACHE with min/max 100/0

[Jeroen]

have you use for foliage kray surface shader??

see it:
http://www.kraytracing.com/wiki/Kray_pl ... ce_Shaders


read this discussion:

http://www.kraytracing.com/joomla/forum ... =viewtopic

yesterday i've rendered an exterior with 25 trees + 12 plants - 1600*1200 px in 2.32min
i love kray

Yep, seen it, used it. Thanks for linking to the threads etc though, appreciated.
Not for me then, will stick to native.

[jure]

I took a quick look at your scene... you used Kray suface options shader but with path tracing. That's not going to be fast because path tracing is rather slow. You need to use Photon mapping with cache irradiance off like Johny said... Caching trees is not a good idea because it creates huge amount of samples that render very slow then. You can also use Precompute filtered+raytrace direct like Johny said. That works well for leafs too and will not create noise.

[Jeroen]

Hey Jure (and Johny), thanks for taking the time and looking at the scene and giving those pointers as well. I did try these options (precomputed with raytrace gave interesting look..) but not that succesfull with them.

Interiorwise, I'm very happy with the results and can go beyond LW speed easily. Blurred reflections etc start to take a more prominent role for me there anyway and LW splotches very easily in such cases. With exteriors it's a bit different. No biggie ofcourse, I got a nice workflow going but always eager to try something else.

I know this scene above is not complicated, and that things would change when comparing alot of blurred reflections etc. But in my huge scenes, that is hardly ever visible, I just need massive amounts of trees and foliage and cached so it renders superfast per frame. I have no issues with a few hundred MB of GI cache files. (and no issues with scenes having 500+ unique objects)

[Janusz Biela]

Hey Jure (and Johny), thanks for taking the time and looking at the scene and giving those pointers as well. I did try these options (precomputed with raytrace gave interesting look..) but not that succesfull with them.

Interiorwise, I'm very happy with the results and can go beyond LW speed easily. Blurred reflections etc start to take a more prominent role for me there anyway and LW splotches very easily in such cases. With exteriors it's a bit different. No biggie ofcourse, I got a nice workflow going but always eager to try something else.

I know this scene above is not complicated, and that things would change when comparing alot of blurred reflections etc. But in my huge scenes, that is hardly ever visible, I just need massive amounts of trees and foliage and cached so it renders superfast per frame. I have no issues with a few hundred MB of GI cache files. (and no issues with scenes having 500+ unique objects)

We wait for update Kray engine render. It some part which must be fix inside.
We know about problems with GI at small objects (for example leafs), but power in Kray is in huge scenes with milions instances and super tonemaping.
I hope we soon receive real displacement and new instance from textures