Experiments with Exit Portals.

[contegufo]

Three experiments with Exit Portals in SketchUp 2015 Mac Edition.

1) Without Exit portals, on the sphere are projected reflected the two openings on the floor. Bidirectional Path. SS=3
2) With Extit Portals, the ball does not reflect the two openings projected on the floor. Bidirectional Path. SS=3
3) With Extit Portals, they reflected badly on the sphere and two openings projected on the floor. Bidirectional Path / Metropolis. SS=3

I am a bit 'confused ....

[Oscar J]

Yes, exit portals are weird.

[pixie]

Three experiments with Exit Portals in SketchUp.

1) Without Exit portals, on the sphere are projected reflected the two openings on the floor. Bidirectional Path. SS=3
2) With Extit Portals, the ball does not reflect the two openings projected on the floor. Bidirectional Path.
3) With Extit Portals, they reflected badly on the sphere and two openings projected on the floor. Bidirectional Path / Metropolis.

I am a bit 'confused ....

How many exit portals do you have? Only on windows?

[pixie]

i've done a quick test and it behaves as expected

[contegufo]

How many exit portals do you have? Only on windows?

yes, two exit portals.

[pixie]

How many exit portals do you have? Only on windows?

yes, two exit portals.

you should have whenever there's light entering your room, as they will be all the light there is coming from background.

[bubs]

i've done a quick test and it behaves as expected

But the bright areas on the floor are not reflected in the ball... Surely this is not 'expected' behaviour...

[Zom-B]

i've done a quick test and it behaves as expected

But the bright areas on the floor are not reflected in the ball... Surely this is not 'expected' behaviour...

It is!
The few fireflies you see in the Sphere ARE the reflections, render that scene over night and you'll see that this noise ends up as the missed reflection!

This issue here is exactly the reason why EPs need some rework, while EPs speed up flat light like from the sky a lot, they slow down such second bounces of small lightsources like the sun or other small stuff like lamps in a HDRI!
See here: http://www.indigorenderer.com/forum/vie ... =7&t=13645

Please redo your scene by closing the wall behind the camera or putting another EP there contegufo.
Also try putting some simple windows (using Arch Glass) on the openings, so you'll have a even more complex scene that is closer to real work usage

[pixie]

i've done a quick test and it behaves as expected

But the bright areas on the floor are not reflected in the ball... Surely this is not 'expected' behaviour...

you're right! haven't noticed, i was focused on the fact that the background went black

[Oscar J]

Zom-B: I still think a few fireflies instead of highlights isn't really "expected behaviour".

[Zom-B]

Zom-B: I still think a few fireflies instead of highlights isn't really "expected behaviour".

Oh sorry, I simply forgot to explain that this light paths are so hard to hit without MLT or Photon Mapping, that it sadly is like that... expected :/
Expected because of the known limitations of the actual Exit Portal Model.

[contegufo]

I am very puzzled if Indigo is a renderer 100% reliable.
Fireflies, noise, EP .......
If I have to deliver an image to a client what to answer him?
That the EP does not work well?
I am then forced to rely on the Global Illumination of Cinema4D?

Basically the EP have problems with 2nd bounce light; I then make the mirror floor? It may be that this is so?

I am disappointed!

[thesquirell]

I don't see a problem here, just use BiDir MLT without Exit Portals, let it cook for a while, and you'll be fine. Everything will be rendered correctly with the right amount of sampling. Experiment with the render settings, and don't expect to just jump inside in one of the render engines and to know everything. It takes practice and patience to learn any package.

Indigo is 100% reliable when you know what you are doing, just as any other render engine. For example, for sufficient caustics, reflections, etc. in a demanding scene, using Vray, with all optimizations while using two computers, it took me 30 hours or so to get that final image. What do you expect of a unbiased render engine, to render it faster then the biased one? Impossible. If you want to try something else, my recommendation is to try Maxwell engine, it's also super accurate, and MLT based, see how much time you will need in it to get a decent, noise/firefly free image. Compare it, experiment. If it's time that troubles you, for a decent amount of work you'll need a farm of at least 10 computers, regardless of your engine of choice, so you can drop that rendering time value significantly. Without that farm you must get used to rendering times of 20h or so, if you're gonna use a single machine, and want that complete noise-free look.

Knowing your tools and how they behave is essential. If I am to render a complex interior scene, with many light paths and specular/glossy materials, I must take into the account the time it'll take me to render that final image, so that I can be true to the client. If I have a single machine, or two machines working in a unbiased rendering work, I must expect long rendering times, and in accordance with it, calculate with it. Otherwise, online rendering farms wouldn't exist, right? Only reliability you need to worry about is the correctness of the rendered result. If those reflections, highlights didn't render at all, regardless of time, then it's the reliability problem. Otherwise, it's just a time problem that is troubling you. You can solve it by adding more computers to the rendering job, optimize your settings, hire a render farm, or just wait out to render it with the resources you have at your disposal. Of course, that doesn't mean we can let Indigo's dev slow down, or forget about speeding things up from the engine itself!

As for the Exit Portals themselves, I hope to see them reworked soon. Can't wait to see how this new Photon Mapping option works, alone and with EPs.

[Oscar J]

I can see why you're disappointed. The exit portals don't work very well, and without EP's, render times can be very long. MLT sort of works, but it takes ages to get rid of the last bit of noise. There hasn't been any significant updates to Indigo in over a year, and unfortunately, it's starting to show.

[Zom-B]

Basically the EP have problems with 2nd bounce light; I then make the mirror floor? It may be that this is so?

I am disappointed!

Simply don't use EPs and buy decent rendering hardware!