I'm just posting to let radiance know

[afecelis]

@Frances: yup, congrats, your gallery is indeed impressive! You say you use Rhino for modeling? I mean, for architectural modeling? I thought rhino was more oriented to organic stuff (being nurbs oriented). And you use Fryrender? You got the beta EA thingie? Is it a standalone renderer? How well is it integrated with 3d modeling packages (I presume via plugins) and which ones are covered? sorry for all the questions

oh yes, final one, what is CHEMA?

regards,
Alvaro

[Frances]

@Frances: yup, congrats, your gallery is indeed impressive! You say you use Rhino for modeling? I mean, for architectural modeling? I thought rhino was more oriented to organic stuff (being nurbs oriented). And you use Fryrender? You got the beta EA thingie? Is it a standalone renderer? How well is it integrated with 3d modeling packages (I presume via plugins) and which ones are covered? sorry for all the questions

oh yes, final one, what is CHEMA?

regards,
Alvaro

Hi Alvaro,

Yes, I use Rhino for about 90% of my scene modeling. It's good for architectural modeling because I have more precise control.

[afecelis]

Thanks Frances! my curiosity has just been sattisfied I'll check how Rhino is doing these days.

[Frances]

i'm currently using:

AutoCAD Archdesktop 2007 -> filelinked to meshes in VIZ 2007 -> OBJ export to blender and blender to indigo.

i use indigo all the time at work and it handles everything niceley,
with very good results.

the blender step is necessary because of the better exporter.
it works quite niceley.

most modeling is done in autocad or made by architects or customers in autocad, as it's that much easier to sweep architectural elements straight onto the project instead of having to handle clumsy meshes. (eg rooftiles, weatherboards, windows, doors, etc...)

That's quite a workflow. I guess since I specialize in interior design viz, I don't have that much overhead when it comes to project integration. My clients give me sketches and catalog cuts and I get to pretty much take it from there.

fryrender seems nice, but it seems to sacrifice precision for speed.
Indigo's GI calculation seems much more accurate and realistic, altough slower. it's like turning max num consec rejects to 10 and max bounce depth to 20.

I'm quite happy to have settled into my role as "Pure User". I did my share of coding shaders and tweaking ascii text scenes, and I'm happy to leave that behind.

It's all a matter of perspective. This renderer or that one, people choose their tools for their own reasons. What matters to me is if it does what I want and doesn't get in my way. Perhaps when the V1 demo comes out, you can try fryrender and make a more knowledgeable assessment of its precision.

[IanT]

I really like Fryrender and I've not seen any obvious evidence of bias in the renders that might suggest mcr is set as low as 10 etc. I'm also 99% sure that's not pure MLT (maybe path-tracing for direct lighting on top of MLT and/or possible a variant of ERPT) which maybe explains why some scenes converge so much more quickly. Certainly, in my experience, an outdoor scene illuminated by a physical sky can converge more quickly with path-tracing than it could with MLT or BiPT.

In practice, a value for max_bounces above 50 will generally result in images that are indistinguishable from one where it's set to 10,000 or "infinity". Due to russian roulette, and with reasonable probabilities for path extinction, a path length as low as even 100 is relatively rare event, and 10,000 will almost never happen within our lifetime (despite what Chema might suggest on the Fryrender forum )

(Welcome Frances )

Ian.

[OnoSendai]

Yeah, it's hard to say how biased it is, if at all, without some vary bare technical scenes to look at, which i haven't seen on their site (might have missed them tho)
For instance, a nice cornell box showing reflected caustics would be a good test.

There's a circumstance where a large number of bounces can be reached that is reasonably common: total internal reflection in a 'waveguide' object. This occurs in a fibre optic cable etc.., but is seen more commonly in the walls of glasses, for example wine glasses. (altho i can't say i've rigorously tested this in real life )

EDIT: another example is along the glass in those glass coffee tables

[IanT]

So true.

Fryrender can never claim to be unbiased until it's confirmed with, for example, a photo/render comparison (similar to the one performed on Maxwell a while ago).

As we know, unbiased'ness is an aspiration, and can't be confirmed as reality without some rigorous (public) technical testing

Ian.

[Frances]

[deleted]

[IanT]

From the fryrender home page:

What is fryrender?

fryrender is a new unbiased renderer that simulates the real behavior of light to produce true-to-life renders with a minimal set of light and material parameters.

Ian, by confirmation, I gather you mean proof that Chema is telling the truth when he says that all the methods for computation within fryrender are unbiased? The way I understand it, "unbiased" would be an approach or method of simulation, not a result. "Physically correct" is the result.

Sorry, Frances, I didn't make it very clear (my fault) ... obviously Chema's telling the truth. I was just referring to the many subtleties involved in actually implementing an unbiased renderer. OK, path-tracing is easy but something using, say, any kind of path mutation strategy, isn't. Of course, pure MLT is quite kind, in that MOST errors in calculating path density etc. show up as obvious errors in the image, but this isn't always the case. An example is transmittance used with BiPT ... an IOR-based scaling factor needs to be applied in one direction but not in the other direction, and this doesn't need to be implemented, even for 99% of scenes with transparent objects to still look correct.

Even the simplest or subtlest of bugs can result in an image that looks OK to most users (even the author), but isn't. The only definitive way to confirm this is by comparing results to photos, a test that we've not seen yet.

For the record, as a commercial product I think Fryrender has a great future for the main reason that Feversoft so far appears to be very active in listening to existing/potential users. I also can't wait to try out RC4 once the demo version comes along

Hope that clears that up

Ian.

[OnoSendai]

Good to see you've been studying your Veach, Ian

[IanT]

Good to see you've been studying your Veach, Ian

Veach is "da man" (so is Ward...)

Ian.

[OnoSendai]

Yup. Veach is a true legend.
His thesis is just.. brilliant.

[Frances]

Ian, I agree that by examining test renders from scenes developed to demonstrate specific aspects, you can visually determine the accuracy of a simulation and detect bugs or flaws in the integrations. It's obvious that you know render engines and render theory and are quite an accomplished programmer. But you need to step outside of the decisions you've made for your own engine before you can objectively view someone else's.

[IanT]

Frances,

Yes you're right. Apart from my occasional rantings about commercial vs. transparent/shared knowledge and algorithms (which I think is what you're referring to ... that was at the end of a "very bad day" by anyone's standards and I hope no-one took offence ) I do think I'm fairly objective about all things technical (for example, correcting fallacies about "infinite bounces" etc.). All I was saying really is that the "unbiased" tag doesn't just happen by implementing an algorithm and yes, this comes from experience, but is applicable to any renderer.

Peace

Ian.

[OnoSendai]

Frances:
I would say that in practice, every nontrivial renderer is somewhat biased. There are just too many subtleties, floating point precision errors/biases/workarounds etc... to achieve some kind of abstract unbiased-ness.
However, it's another matter to determine whether a renderer is sufficiently unbiased in practice, for common scenes, as to be effectively unbiased, and I do think this is possible.

EDIT: perhaps I should substitute 'physically accurate given the approximations of the real laws of physics chosen, and unbiased', for 'unbiased'. But I hope you get the idea anyway