Hi All,

I've seen a competition run on several different sites over the years, all with the same basic premise. and its a good one.

Basically you build a scene, with a fixed camera and environment, then each entrant loads the scene into there app, and attempts to render it (changing lights, materials and textures to their liking) to create the most realistic end result they can (without postwork).

I was wondering if people here would be interested in doing something like this?  I have the modelling abilities to create a scene, and I can even offer a prize (my car materials), although you should really be more into it for the challenge, rather than the prize :p

Do it!

I think it's a great idea :)  let me know if you'd like to do a contest or a challenge ;)

I'll play :)

yes, I would like to see the scene.

Sounds like a very good idea! 

Interesting.  I could possibly go for that.

Yeah I'm up for it.

Good Idea.....reminds me of Renderwarz..many many  moons ago. (cough cough) so I herd anyway. :P

ok, I will build up a scene this weekend.

I will most likely build an interior scene, first thing that comes to mind is a foyer in a modern home, wood and metal (if you choose) with a staircase, front door, windows, coffee table, plants, rugs and the like.

Feel free to throw out ideas, remember the scene should be detailed enough to be realistic, but not so detailed that all the "realism" in the render comes from the scene, rather than the settings. Other than that, I can model pretty much anything

Sounds like a great idea to me. :D

It's not going to be limited to rendering in Poser though, is it?

this is the poser forum, so for the competition yes.  but that doesnt mean you cant render the scene in another program just for kicks

I'm down, sounds like an interesting challenge. Are we allowed to add anything? maybe a small detail or whatever? I don't have anything specific in mind, just asking if anything comes about.

Quote - Sounds like a great idea to me. :D

It's not going to be limited to rendering in Poser though, is it?

LOL - you plan to participate in a regatta by flying over it in a jet?

Poser is really weak at interior lighting. We have IDL now and that helps, but for the fact that every corner has artifacts and the rules are no postwork.

You of all people should know that only counts if the scene is not built for poser :p

Regardless its an idea only, however this is more the style of interior I was thinking of creating :

http://static2.bigstockphoto.com/thumbs/7/8/4/large2/4871647.jpg

I google image'd it, so I wont embed it

--edit--

sorry I missed your question.  I dont think it would be fair to allow people to add objects to the scene, only because the quality of the objects available for each person depends either on their library, or there other application and skills in modelling. Not everyone has the same library and modelling applications.

For this first activity I think we will keep it simple :

Can Do :
add/remove lights
add Textures
add Materials
add Environment (as in Poser Env, volume fog etc)
Color/Gamma/Brightness correction of final image

Cant Do :
modify camera
add additional objects/particles/sprites/polygons to scene
hide, or otherwise make invisble objects in the scene
Render in an application other than Poser
Using postwork to fix or modify the output render past the above allowed

does anything need clarifying?

Sounds good to me.

Clears it up for me.

Another Can Do I just thought of

Add an Environment Sphere.

I was originaly just going to model one along with the scene, however the mapping of the sphere may not be the same as the images you frequently use on your env sphere, so instead I will make it so you can use your own env sphere.

can anyone see this being a problem? or any reason why this shouldnt be allowed?

Nope, I think adding the env sphere will help alot with the quality of the scene and there are excellent free ones. :)

Quote - I dont think it would be fair to allow people to add objects to the scene, only because the quality of the objects available for each person depends either on their library, or there other application and skills in modelling. Not everyone has the same library and modelling applications.

I take this to mean then that no human figures will also be allowed right?  (had to ask because this is Poser after all) Because the same things apply, some may have just default figures and others more realistic hair, clothes, etc?  So just to clarify, this will be a render of the scene as you set it up but we can change the lights, textures, materials and add environment or an environment sphere.  And all renders will be with the same camera settings and show the exact same thing from the same perspective, right?

Quote - Poser is really weak at interior lighting. We have IDL now and that helps, but for the fact that every corner has artifacts and the rules are no postwork.

Every corner has artifacts? Is that due to pooling of the photons as they try to decide which way to bounce when confronted by two flat surfaces at 90 degrees to each other?

Or maybe a search distance that's too wide by default?

I'm not seeing too many options for the GI in Poser. I'm aware of the Render Firefly script additional options, but it doesn't add much. I wonder if the internal settings are just not optimized for Poser's use.

In Mental Ray for example, you can have problems in corners with artifacts due to both the reasons I mentioned above. Two non-MR ways of potentially fixing the problem are to either bevel the corners in slightly to alleviate the bounce issue, and/or to create depth to the walls outside of the room to prevent "confused" photons from reporting back on what they see outside the room. In other words, use thick solid walls, no single-sided planes.

Of course MR has oodles of options to also combat such problems, such as expanding or limiting the search distance for each photon, or to combine it with Final Gather or irradiance particles. As well as options for every imagineable aspect of the photon's trip through a scene.

I'm guessing Poser's GI would be better if they gave access to some of the controls - more options.

I'm also betting that some of that artifacting could be solved with rounder corners or "thick" walls.

you get spotty-ness in the corners because of the number of bounces requires for the light to be able to exit the corner, considering that its likely to have already bounced once or twice, because lights rarely points at corners :p

Kalypso, you are absolutely correct. The idea is for people to show off there rendering and node skills, rather than scene setup and prop quality.

I will ensure that there are plenty of material zones for anyone wanting to go purely node based, and everything will be UV mapped.

On the way home from work I started sketching out ideas, that image I posted earlier really inspired me architecture wise, I will be using Chief Architect to build the scene, to ensure that the environment's structure is accurate to US standards (help with realism), I should have something to show you this weekend and the final thing sometime next week!

Quote - you get spotty-ness in the corners because of the number of bounces requires for the light to be able to exit the corner, considering that its likely to have already bounced once or twice, because lights rarely points at corners :p

Well this is true but I was  operating under the assumption that the bounce level was set high enough to avoid that. I was replying to bagginsbill, and I would assume he would have already taken that into account before saying "every corner has artifacts"

If it's simply a matter that photons get "stuck" in corners in Poser and that's that, then something obviously isn't right with how it's being calculated, because it's not typical behavior in other GI render engines to not be able to avoid it with options.

Anyway, I'm looking forward to seeing what you come up with!

"Render in an application other than Poser"

how about using Luxpose?

Quote - > Quote - you get spotty-ness in the corners because of the number of bounces requires for the light to be able to exit the corner, considering that its likely to have already bounced once or twice, because lights rarely points at corners :p

 

Well this is true but I was  operating under the assumption that the bounce level was set high enough to avoid that. I was replying to bagginsbill, and I would assume he would have already taken that into account before saying "every corner has artifacts"

If it's simply a matter that photons get "stuck" in corners in Poser and that's that, then something obviously isn't right with how it's being calculated, because it's not typical behavior in other GI render engines to not be able to avoid it with options.

 

Anyway, I'm looking forward to seeing what you come up with!

It's not a bounce level issue. No photons are "stuck".

It is a fundamental problem with the speedup tactic known as "irradiance caching". Just to be clear, it is not that Stefan implemented IC with a bug in it. Rather, IC, as a technique, has certain limitations. These limitations can be avoided and there are things you can do to minimize the intrusion of artifacts, but if you're using IC at all, it is not possible to definitively eliminate artifacts altogether.

Yes other GI engines don't have the problem, but in every case those are engines that are not using IC. While I do not have any other renderer featuring IC in its algorithm, other forum members have demonstrated renders for me showing the same artifacts in other apps when IC was used.

Stefan Werner, the SM engineer who built the IDL component and maintains the Firefly renderer, explained all this to me. I confess I did not grok the particulars. But having been told by the author himself that it is a fundamental flaw in IC, and having been shown the same artifacts in other renderers using IC, I'll take it as a given that what I've been told about the problem, and what I'm telling you now, is largely correct.

I will now demonstrate.

Ground plane.

Some overlapping primitives.

My EnvSphere, self lit, with a very gentle light blue-to-white gradient.

One infinite white light at 20% intensity.

All materials are simple white diffuse-only with diffuse value at .7 or .8, so there's no question of bounced light intensity blowup.

Being that the GI will largely be driven by the EnvSphere, and it exists in all directions, there's no problem with a photon "finding" a light source.

Using the D3D Render Firefly dialog I set very aggressive (slow, high-quality) values on everything:

Irradiance Sample Size=5 (half of normal, creating four times as many sample points as usual)

Bounces=6 - plenty enough to find the sky. Note that when two planes meet at 90 degrees, sky is found in 2 bounces at all times, and within 3 bounces at a 3-plane corner. I used 6 just to be sure that prop-to-prop bounces would work as well. Since the sky is reached in 3 bounces at any corner, then a pair of corners reaches sky in 6, no matter what. 99.9999% of the samples in the render reached the sky within 3 bounces.

Samples=1000 - Each point IC sample sent 1000 rays to examine the rest of the world. Very aggressive.

Irradiance Cache - 70. Fairly aggressive - does not use the cache unless preliminary sampling indicates less than 30% error. Note that the artifacts show a luminance error far, far in excess of 30%.

The results are attached. Very bad.

But it was only a 24 second render!!!

The artifacts are gone. However, render time was 42 minutes. That's 105 times longer than with IC enabled.

Keep in mind that I have a honking fast computer here. 42 minutes for a biased renderer doing a few props is an eternity. If I actually had an interesting scene with glass and other stuff, we'd be talking many days of rendering here. I'd rather use LuxRender for accurate GI. Even 24 hours in LuxRender would be better than 6 days in Poser.

[Addendum: I just noticed a new artifact - different kind - between the two big boxes on the ground. Do you see it? It is also between the middle box and the big sphere. It's not in the first render. So we're screwed - one kind of artifact with IC on, another kind with IC off.]

I see what you mean about that second artifact.  Looks almost like a "negative" shadow.
This is where I wish I still had access to VRay - that uses irradiance caching and I'm pretty sure I've never seen artifacts like the ones you get on render 1. 

I've never heard anybody say VRay shows them. I think it was Modo that does, or did.

Algorithms change over time - perhaps there are new ones but they are still called IC.

"So we're screwed - one kind of artifact with IC on, another kind with IC off."

It would take me awhile to remember all the render engines I've tried over the years. Some are better than others but I have yet to find one that never makes mistakes.

templargfx,

Poser IDL has a problem with glass - it doesn't see the surfaces on the other side as being lit quite as much as they really are. This prevents sky light from filling a room correctly via a window.

My workaround is to make glass panes a separate actor from the wall. This makes it possible to disable "visible in raytracing" on the glass. Then IDL sees through it correctly.

If you were to model any window glass as a separate prop, this would keep that option open.

If the window is paned does that mean that once you disable "visible in raytracing" you will not get the separate panes on the light being cast and instead just one big square of light?

I will knock up a quick version of my current sketch and see how it renders, then decide if we "move this outside" :p

Quote - If the window is paned does that mean that once you disable "visible in raytracing" you will not get the separate panes on the light being cast and instead just one big square of light?

If you're talking about the strips of wood separating the glass panes, these are called muntins, and they would continue to be visibile in raytracing and casting shadows.

I'm asking only that the actual glass rectangles be a separate prop. If there are 200 of these they can all be one prop. The rest of the house (walls, doors, window frames, muntins, and sashes, etc.) do not need special treatment. Just the panes of glass. (These are sometimes called "lites".)

The interesting thing about house modeling is the window panes for an entire wall can be just one big rectangle, centered in the wall. They will only be revealed where the wall parts leave a whole through the wall.

Ok, thanks for the clarification :)

Quote - Here is a quick render of the house I built for my parents. very low settings (15% IC, 3 bounces, 99 samples) but you can see obvious problem areas.

I will knock up a quick version of my current sketch and see how it renders, then decide if we "move this outside" :p

If that's the model you're  going to be supplying, it looks great. :-)

I'll be following this but don't know if I'll try.

Although it would be great experience since I'm trying my hand with lighting now.

Of course I'm not the master that BB is and I'll be very interested in seeing his render. :)

Quote - It's not a bounce level issue. No photons are "stuck".

It is a fundamental problem with the speedup tactic known as "irradiance caching". Just to be clear, it is not that Stefan implemented IC with a bug in it. Rather, IC, as a technique, has certain limitations. These limitations can be avoided and there are things you can do to minimize the intrusion of artifacts, but if you're using IC at all, it is not possible to definitively eliminate artifacts altogether.

Yes other GI engines don't have the problem, but in every case those are engines that are not using IC. While I do not have any other renderer featuring IC in its algorithm, other forum members have demonstrated renders for me showing the same artifacts in other apps when IC was used.

BB, you ought to tell him to look into a trick that Mental Ray has for GI. (At least the Softimage version does, and I assume the same goes for Maya and 3ds max) - "Importons".

Importons are basically the same thing as photons, except the name is derived from "important", as in what's important to the render. Basically that means that instead of the photons being fired from the lights, they're fired from the camera, and photons are only bounced around for what's important in what's framed up in the camera's view. So instead of hundreds of thousands of calculations being made for photons that aren't even affecting what you're seeing, the render engine is only calculating what's necessary.

I appreciate the detailed explanation of how Poser does GI and IC. I messed around with GI in Poser a little earlier today. Enough to know I don't like it. Needs more options and it's just way too slow.

Considering this is Poser's first version of Firefly with GI in it though, I'd say they're off to a good start at least.

Quote - [Addendum: I just noticed a new artifact - different kind - between the two big boxes on the ground. Do you see it? It is also between the middle box and the big sphere. It's not in the first render. So we're screwed - one kind of artifact with IC on, another kind with IC off.]

o.k. I'll try this scene, bill.  I dunno why that artifact appears.  it only appears with a gradient img on envsphere?

So is this dead before it started or has it been moved somewhere else?

I think we're actually giving templargfx some time to model it :)

Okay I misunderstood I guess. I thought the model of the kitchen/dining room a few posts above was what he was going to upload to use.

haha no, the model of the kitchen was a house I designed for my parents a few months back, that render was a quick one in response to BB's post about problems with GI in interior scenes (which is visible in that render)

The scene I am building for this contest is still interior, however I have changed it a little to have 2 story high glass windows in the front of the foyer, and hopefully (having trouble getting it modelled correctly) a skylight in the foyer centre.  This should allow more than enough light to help reduce the artifacts associated with interior rendering (you could always turn the inside lights on too!, or do a night render!)

I would say the design is 80% complete, after that its export, breakup and cleanup the model, then its into max to model some furniture and fittings.
Once I export the design from Cheif Architect I will do a quickie render so you can see where I am at!

o.k., at IDL IC = 100, I can reproduce bill's shadow boundary artifact in the corner reflector geometry group.  the coder for this is aware of it AFAIK, but somebody may wish to remind him. these artifacts are occurring at unwelded seams with no beveling or irregularities of any kind, or at seams which represent the intersection of two solid bodies, even tho real cubes have slightly beveled irregular edges, and two real solid cubes can't occupy the same space.   however, one would still like to see these artifacts eliminated, if poss.

I  might participate in the challenge.  Looking forward to seeing the scene.

@ MIss Nancy:

For what it's worth I don't think any GI engine is going to properly calculate GI in corners made by two intersecting but unwelded objects. The render engine knows that it's hitting two distinctly separate objects and just doesn't behave properly like light in the real world would. That's not just a Poser problem either, as both Mental Ray and VRay do the same thing, the difference being that those engines have far more options to use to combat the problem.

That's really the only problem with Poser's GI - a lack of user options. Mental Ray, for example, has so many options and possibilities you can drive yourself crazy trying to decide where to start, but in the end it's all worth it.

( And I know someone will read this and be tempted to say, "yeah well Poser only costs a tenth as much"... my point being, if you're going to do GI, you might as well implement it to your fullest capacity and I'm sure the programmers can handle it. ;-) )

Having said that, I've recently done some simple GI tests with Poser and GI in a totally enclosed 3D room and have gotten fairly reasonable, passable results with walls that are physically connected and slightly beveled, like real walls would be. The artifact problems I'm having are mostly with splotchy walls, but then again I'm not really pushing its limits anyway, but I can get decent corners at least.

I'm in! 

I think there should be 2 prizes. One for Bagginsbill because he's a guru and wins by default. And one for the rest of us :)

Quote - I'm in! 

I think there should be 2 prizes. One for Bagginsbill because he's a guru and wins by default. And one for the rest of us :)

LOL. I thought about that. It's almost not fair for me to play. Nobody has as much time as I do to tweak like a madman and now I have a spanking fast computer as well.

I'm thinking about buying one or two more computers and setting them up in a serious render farm.

I'm curious about your computers specs now Bagginsbill...

Quote - It's almost not fair for me to play.

Noooooooooo! You have to play!!!