REALLY slow rendering

[SmartDen]

sure! you have to read old forum threads

[psor]

@doublez

Exit portals are useful for speeding up the rate of convergence of interior renderings, when the
interior is lit by an environmental light source, such as the sun/sky model.
Exit portals are placed over the openings between the interior and the exterior environment. These
openings are the 'portals' in the scene.
Exit portals make the rendering process more efficient, because paths passing through such
openings can be more efficiently sampled when explicity marked with an exit portal.

Requirements for exit portal usage:
• If exit portals are present in the scene, then all openings must be covered by exit portals. In
other words, all possible paths that start on the camera, and then travel through space or a
transparent object, and then escape out of the scene into the environment, must be blocked by
one or more exit portals.
• The geometric normal (defined by triangle winding order) of an exit portal mesh triangle, where
reachable by some path from the camera, must point into the interior of the scene. (i.e. The
front side of the mesh faces should be visible by the camera)

@Labello

Yes. Take a look at the attached sheets. There is no "total white" in
real world. I thought Indigo would clamp 1,1,1 to 0.9,0.9,0.9 already,
but it seems I'm wrong. Nik, didn't you mention something like that
in that past? ;o)

White (very white) glossy paper : Reflectance 88% --> 224,224,224 RGB
White mate paint : Reflectance 81% --> 206,206,206 RGB

You should´nt rise this 224 reflectance, very few materials have higher reflectances in real world.
Reflectances avobe this number increase rendering time and produce results far from reality.
It´s very important to set reflectance under 224 (88%)

Setting 100% reflectance materials (pure white materials) increase rendering time 3,5X (in this test)

So if you think your room is not white enough, you've to change the
exposure and/or white balance instead to increase the RGB value.

Anyway, here you can find the original thread in the M~W forum.
Sorry but you've to register there to read it.





take care
psor

[Labello]

Thanks a lot psor! that is great! *saves the images*

but i still didn get rid of the issue.

i completely remodeled the room. i started with a cube. the first thing i did after creating the cube was flipping its normals. is there any possibility to show the normals in blender? i dont see any difference between different normaldirections.

i attaced the new scene again.

[doublez]

One way to do it is go to face select mode (F when in object mode) and check. I know there is another way to see while in edit mode but I don't know how to do it.

[psor]

@Labello

You're very welcome! I checked your new scene and can't find big issues.
If I do render it with your settings I get ~20k s/s which is ok for this
kinda scene. The default Indigo settings are way off tho. Dunno if
blendigo comes like this, but it's bad!

Change the render settings from:

Code: Select all

LM probability: 0.1
Max Change: 0.02
Max num consec reject: 100

to:

Code: Select all

LM probability: 0.4
Max Change: 0.01
Max num consec reject: 1000

I did also change your shader settings from 0.9 to 0.8 which should be
better. You can use biPT for quick previews and for final renderings biMLT
for this kinda scenes.

With all those tweaks I get ~33k s/s with biMLT.

And I just want to mention that you can keep the way you did your
exit portals in the last version. It's enough to have a simple plane
as exit portal, there is no need for a box. It is just important that
all openings get covered. When I say covered I mean that the exit
portal should slightly intersect with the frame of the window to make
sure that there is no spacing.

nb: For tone mapping you should save the IGI file, then open
it in Violet and color correct your image there. Don't bother to much
to make it right when you do render, do that in post.


@SmartDen

Why do you use settings like the above as default in blendigo?





take care
psor

[Labello]

OK guys!

now it works nice!

does it take any positive effect if i bevel all edges in the room to scatter the light a bit more smooth?

[Labello]

sure! you have to read old forum threads

btw... i dont think this comment was neccessary... sry but it sounds a bit rude to me >.<

[psor]

Mach dir keine Sorgen Labello ... der SmartDen ist'n "Netter"! ;o))

And yes bevel the edges, but not to scatter light but to make the
scene look more realistic, as you might know there are no sharp
edges in a room! In general it's good to bevel everything.




take care
psor

[pxl666]

2. deleted your portal planes ( I see you have 1 hidden already - I didnt notice this first time) and replaced with a portal cube closely encasing the whole room - normals inward

is this 4 real????is this same as capping openings with EP's?

[psor]

@pxl666

I would say yes, but I'm not sure what kinda impact this would have
on the render time. As I do remember Nik said something like:

"Keep the 'exit portals' as small as the openings they have to cover."

So I would do it as he said. Make them a little bit bigger
as the opening and let them intersect a bit so there is no
spacing at all between your opening and your 'exit portal'.




take care
psor

[BbB]

You can perfectly well encase your scene in one huge exit portal. You won't get much speed increase than by using no portal though. The point is to save time by telling Indigo not to shoot rays where they're not needed. By the way, you're free to position your portals wherever you like. But since any space outside the portal will render black, ensuring they cover the entire opening is just a common sense way to avoid seeing the outline of the portals, and therefore these black areas...

[Labello]

Does there exist any linux-version for violet?

as far as i know WINE isnt able to handle the MSI-setup >.<

wow i even got rid of the textures on my own... i love the exporter!

[psor]

@Labello

I made a "package" for wine and it works great. Go and download it here.
Copy all files into a directory and start Violet with wine.




take care
psor

[Labello]

but i have got the linux-binary running of indigo^^

[psor]

Ok, I updated the package to include all needed files and it should work for
you as it works for me. You can put the files in any directory now.




take care
psor