'Energy Conservation' in Vray (and others)


#75

Perhaps some day you’ll explain to me how it is you think you’re “locked out” of anything when you can simply add shaders together however you want.

The renderer isn’t enforcing energy conservation, it’s just the shader. Add as many as you want together; there is nothing stopping you. If VRay (or any other renderer) was really trying to lock you out of anything, they wouldn’t have provided the “Additive Mode” option on things like VRayBlendMtl, and they would be culling and enforcing energy conservation during the rendering process. They’re not. Their provided shading models (correctly) apply masking to the diffuse/reflection/etc. Beyond that, you can do whatever you want…incorrect as it may be.

That’s great, but they can’t. We live in the real world with real materials and real lights, and I don’t see any filmmakers struggling to achieve artistic results because of it. Get creative with your lighting, don’t get creative with completely arbitrary energy return on your shaders.


#76

OP, if you have problems or do not understand something, you do a better service to yourself to ask questions instead of making assertions. CG is an evolving science that strives to be physically accurate at least as a default position. From here we there are many options to break the so called physical accuracy to achieve certain looks. If non realistic rendering is what you need then ask politely and someone will help you.

Also try not to sound like you are mentally insane when interacting on the internet.


#77

What is it about;

  • “I’m just tired of doing workarounds for things that don’t help me in the first place.”
  • “Who else has never gotten a single benefit from this ‘feature’, only extra work, extensive node networks and complicated hacks to get around?”
  • “I know the workarounds, I’m just tired of taking the extra time for no good reason.”
  • “Thanks but I applied the workaround a long time ago. I’m just sick of doing workarounds for a feature that takes control away the artist, and locks it.”

that you don’t understand?

Yes there’s nothing stopping me from setting up 50 shaders, then on #51 realizing that I don’t have EVERYTHING 100% PERFECT, and starting all over again from shooting HDR’s on-set, simply because I can’t turn off EC for that shader. My fault for not being PERFECT, like YOU, and not having a Multi-$Million pipeline. I should be ashamed.

Otherwise, the IMPERFECT lighting/rendering - even at ILM - REQUIRES some flexibilty in the shader. Would you like to forced to render subsurface scatter in every single plastic or wood shader, no matter how insignifigant in the scene it is? Then just stfu.

That’s asinine, you could use point lights as the same argument. “It’s OK that you can’t turn off energy conservation, because they still let you do all kinds of other unrealistic things.” I am the one who’s been pointing out all the unrealistic things we can still do, not you.

That’s not the fucking point, you arrogant p.o.s. They WOULD IF THEY COULD. You’re still professing that cg artists should be every bit as restricted as practical artists. Despite my repeated reminders that supervisors and directors CONSTANTLY ask for unrealistic stuff. I would f’ing love to be there when you tell a supe that ‘no, I won’t do what you ask, because it’s not physically correct’.

So those guys building 2-story robots that walk, talk, emote, fight, transform, fly, and destroy skyscrapers, are having an easy time of it? The very idea that no one asks for anymore in cg than you can do in real life is unbelievably stupid.

That’s funny, because I had to “get creative” with lighting just to get something that looked NORMAL. A simple ‘off’ switch is ALL I needed to avoid wasting time experimenting with workarounds. Just like you get with raytracing, motion blur, dof, global illumination, etc. etc… you do realize you can turn those off, right??


#78

Really? Can you change the spread, color, or falloff of an IES light? Can you turn off shadows?

Now you’re putting title over content. What makes you think he has an art degree - that he says “well, ILM does it” all the time? Anyone who thinks “phyisically accurate” is more important than aesthetics, needs a goddamn art class. Our job is NOT to produce things that any schmuck could go out and photograph on his own. His imdb page is shorter than mine, so just stow this BS where the sun don’t shine. I fucking swear to god, the number of people who believe in the Emperor’s New Clothes just makes it embarrassing to be human sometimes.

Do they change the falloff? Do they have to worry about render times? This is ridiculous, you’re just repeating the same argument that cg lighters should have the same f’ing limits as real lighters, even though we have supervisors that CONSTANTLY ask for completely unrealistic things.

THEY DON’T HAVE TO USE DIFFERENT RENDERERS AND SHADERS PROGRAMMED BY A DOZEN DIFFERENT PEOPLE EITHER. They don’t have to use INACCURATE lighting like Interpolated GI, or cg lights. Unless you can somehow argue that all these renderers are in fact SIMULATORS, your argument is worthless. And until practical lights come an “invisible” option, then it’s also just plain wrong. It’s absurd to say “they have no limits” when cg lighting offers SO many more options.

Is there something about;

  • “I’m just tired of doing workarounds for things that don’t help me in the first place.”
  • “Who else has never gotten a single benefit from this ‘feature’, only extra work, extensive node networks and complicated hacks to get around?”
  • “I know the workarounds, I’m just tired of taking the extra time for no good reason.”
  • “Thanks but I applied the workaround a long time ago. I’m just sick of doing workarounds for a feature that takes control away the artist, and locks it.”

… that makes you think, that I think, that workarounds are not an option?

Gee thanks for repeating the same juvenile BULLSHIT that I just pointed out in my last post.

Please remember these words the next time your supervisor asks for something to be brighter, and then says “why is the reflection darker?” when you try to do what he asked.

And not ask for any improvements. Just do more work to get the same result, quietly.

That’s great - do you put “physically accurate” before aesthetics?


#79

Ok, fair enough, here’s my question.

What is it about:

  • “I’m just tired of doing workarounds for things that don’t help me in the first place.”
  • “Who else has never gotten a single benefit from this ‘feature’, only extra work, extensive node networks and complicated hacks to get around?”
  • “I know the workarounds, I’m just tired of taking the extra time for no good reason.”

and especially:

  • Thanks but I applied the workaround a long time ago. I’m just sick of doing workarounds for a feature that takes control away the artist, and locks it.”

that makes people think I need help with the shader?

Well considering that people seem to think that the earth being round is “insane”, I’ll take insanity, thank you.


#80

Let it die guys, I feel like we’re in the max forums… :smiley:


#81

Yes, multi-million dollar pipeline of textured assets, VRay, and HDRs shot with a 5D.

I literally have no idea what we’re talking about anymore, and I’m sure you have no idea what we’re talking about, so until there’s a .ma file, I’ll just send along an example of how easy it is to make a non-conserving material…and I’m out.

You speak like this is a non-stop issue for you, so I don’t see why you can’t put together a sample file for us to look at. If it’s too uncommon an issue for you to find a file with problems, or be able to make one…why are we even having this discussion at all? You know there’s render passes too right? You can just crank up reflection (or anything) in comp. Render out multimattes and you can control it even more.

https://dl.dropboxusercontent.com/u/26845156/Terribly_Ugly_Shader.mb

Cheers.


#82

Terribly_Ugly_Shader.mb

This is why you people can never be trusted. Lies lies lies.


#83

@guccione, how I know that about him is because I work with him and I can vouch for both his knowledge and talent. And may I ask for you IMDb page? I’m also curious who I’m talking to and the name you are using on the forum, gives me little to go on and forces me to make assumptions.


#84

Making a lot of new friends I see, Guccione?


#85

You’ve “lit hundreds of shots in tv and features” all from home? Shoot your own hdr’s and paint/grade them?

Because locking features ‘on’ is STUPID. As I’ve pointed out, in not-so-many words, a dozen times now.

“And you know for a fact that this works with vray hair shaders? Or shall I dick around for another 2hrs to find out that it doesn’t work, just for the chance that you can continue to claim that only the most ‘physically accurate’ features should be allowed in 3d.”

I’m sure you have no idea what we’re talking about

That’s a bunch of crap.

The entire conversation so far;
“I’m sick of doing workarounds for a feature that can’t be switched off”

““I’m sick of doing workarounds for a feature that can’t be switched off””

“”“I’m sick of doing workarounds for a feature that can’t be switched off”""

“But we need this feature. Because I like to tell my supervisor that ‘No, I can’t do that, it’s not physically correct’ - since that’s more important than aesthetics. And because ILM uses it. Just do a workaround.”

That’s utterly ridiculous. Realism is one aspect used to create good visuals. Where it doesn’t help, you do not use it. Luminous white eyes are in almost every Pixar character, and self-illumination is included in most diffuse or all-purpose shaders. How “physically accurate” is that?

Sure, that’s because they’re selling it as a photoreal renderer. They may also like the way it looks. But it’s pretty silly to act like ‘physically accurate’ is their ultimate concern when they still use shadow maps, point clouds/brick maps, and reflection maps, isn’t it? (and please don’t try to claim again that shaders have to be physically accurate, but not lighting; that’s just weak backpedalling). Put a frame of Monster’s U next to a frame of Corpse Bride, then ask yourself how much they really care about realism.


#86

I see no reason why a shader shouldn’t allow energy conservation to be turned off, under perhaps an ‘advanced’ section, with a warning that things may break somewhere.

Having been on the Maxwell testing team for many years and also testing/following the development of other renderers, I totally understand why energy conservation has become the norm. People in this thread are already WAY ahead of many many users’ understanding of lighting and shading by even knowing what energy conservation is. There are an enormous amount of people out there who will push and pull shading attributes around without understanding them and then complain on forums or to the renderer devs that they’re getting artifacts like NaN/divide by zero, black pixel, super white pixel, unrealistic GI results or noise in their renders that won’t clear up.

In the end the renderer is doing math and the more you bend the math the more likely things are to get out of control somewhere and return a problem, either visually or in the form of a crash or excessively long render time.

By imposing some restrictions like energy conservation you are:

  1. Preventing users from breaking the renderer.
  2. Helping less experienced artists to achieve pleasing results.
  3. Simplifying the development of the renderer. You don’t need to start having GI, motion blur, sampling etc algorithms that can handle unexpected shader results.
  4. Starting from a more physically plausible baseline.

To a certain degree it is catering to the lowest common denominator, artists without technical understanding. It just so happens that it also approaches reality which often tends to be the desired outcome anyway.

But sure, have the option to turn it off. I see nothing wrong with that.


#87

People who constantly misrepresent you are not looking to be friends -


#88

You can ask…

( sorry, one of my favorite lines from galactica, always wanted to say it :slight_smile: )

I’d rather the discussion not be judged by title or some contest, but by content. Like how many times I’ve had to repeat myself, and how many times I’ve made points that are completely ignored. Whatever assumptions you’re making are probably outside the scope of the discussion, trying to judge my motivation or something? Anyway, none of that should be necessary.


#89

Nothing is locked.

You can disregard energy conservation in two seconds via a VRayBlendMtl in Additive Mode.

The workflow for non-energy conserving shaders is a node heavy setup of fresnel blending against the diffuse component, the reflections, another set of blending if you want refractions, and even more if you want SSS, etc…all of which will never compute as fast as compiled code dedicated to the task.

Considering 99.99% of the time you want energy conservation, and considering it’s by far the more elaborate setup to have to recreate if it’s missing…it should absolutely be the default, which it universally is.

Lastly, are you NOT outputting render passes? They exist so that if you want more reflections, you just boost the reflections in comp without having to worry about what was actually rendered…and multimattes to further isolate selections.

However, if you couldn’t get a VRayHairMtl3 to appear like blonde hair, you were definitely missing something in your settings.

Our “multi million dollar pipeline” you keep talking about is essentially no different than what people are doing at home. Most of our software is basically the same as off the shelf versions, and it’s really the data management, publishing, and all of that stuff where the TD side of things take over and where the money goes.


#90

Hi Guccione, may I ask which version of V-Ray are you using?
It seems all the points you raise with the V-Ray IES lights are already there, at least in the V-Ray for Maya version 2.45.01. Maybe that could be the issue? I’m not sure. :slight_smile:

Yes, by changing the IES file -I guess if you want full control of a CG light, it would be best to use a spotlight, obviously as IES are measured profiles of lights - that is their sole intention.
http://www.photometricviewer.com/

That is a really cool program to quickly toggle through the different profiles.

Yes, either with temperature (kelvins) or whatever color you would like, pink, purple, file texture using the color mappable attribute…

Yes, with the cutoff threshold, I suppose one could also map something to the intensity possibly like a ramp.

Yes, as well as individual and accurate controls for Diffuse, Specular and Area Speculars. In V-Ray 2.45 there is also a parameter to change shadow color or use soft shadows.


#91

This is my interpretation of what this troll wants:

  1. “I want my VRayMaterial to have a checkbox just like mantra surface, where you can turn off energy conservation, or at least to behave like Arnold’s aiStandard where I can take care of energy conservation by my self”

  2. “I want the VRayHairMaterial to produce beautiful blond hair”

My answers would be:

No can’t do, just use the other suggestions like vray blend mtl, passes and multi mattes.

I can’t understand why this seems so hard, since color correcting our shots is as important as look dev. And as others have said, you’ll want energy conservation 99.9816 % of the time, unless you’re doing FX like lightnings or thelike.

Beautiful blond hair is really hard to achieve. Best results I’ve got in the least render time, with the least GI artifacts have been with arnold. So try that.

Q. for the troll: Are you absolutely sure you are properly using linear workflow ?


#92

Then why do you have to work - around it, genius?

“And you know for a fact that this works with vray hair shaders? Or shall I dick around for another 2hrs to find out that it doesn’t work, just for the chance that you can continue to claim that only the most ‘physically accurate’ features should be allowed in 3d.”

I see, you don’t know if it works. I should experiment for (and waste) another hour to find out, because you like inflexibilty.

^Fixed it for ya

You still seem to be arguing that I don’t want the feature to be offered, when I keep saying that I want it to be an OPTION, just like EVERY OTHER FEATURE.

No energy conservation - oh how horribly fake looking.
https://www.youtube.com/watch?v=6Kt3WR0J5Vk
https://www.youtube.com/watch?v=YeXDSYF2xDk

Half of these jet shots have energy conservation (vray), half don’t(lightwave). Tell us which is which.
https://www.youtube.com/watch?v=_sdJPn_PRWg

Energy conservation is a MINOR improvement, that does not justify workarounds.

Yea I’m doing all that. Do you think it’s a good idea to send renders to the compers that have the wrong colors?? And just hope they get it right… instead of actually spending time making the image better? All because a feature is locked, and assumes that every single thing that comes before it is 100% ‘physically accurate’. I don’t.

So it’s ‘only’ a six-figure pipeline? Does every little boutique have that much to throw around? The point is, you have far less to deal with than someone at home or at a small studio, so stop telling everyone how ‘easy’ it is to do yet another workaround.


#93

Really - so maybe it is just Vray. And I guess having an off switch doesn’t cause any problems.

“Thanks but I applied the workaround a long time ago. I’m just sick of doing workarounds for a feature that takes control away the artist, and locks it.”

3D artists have to do stuff like that all the time.

~ Troll


#94

I haven’t tried IES lights for a long time! The only reason I brought them up was to make the point that it’s utterly impractical to use maximum physical accuracy in 3d rendering. Like if we had no choice but to stick to the manufacturer’s specs, and we couldn’t turn off shadows.