maya 2011 new ibl mode?


#7

BSDF Shading is a separate and potentially more complicated subject. You can look under the mental ray documents for an explanation of what is built-in. It has some limitations and a couple bugs in 2011. You may also need SP1 to be sure it works. The built-in shaders are examples of what can be done rather than full fledged shading nodes. But with something like mental mill, you can begin making your own.

The built-in IBL is very much like environment dome lighting. It’s just smarter and easier to use. FG will add a secondary (or more) bounce beyond the direct environment lighting. Also, IBL at low quality generates grain instead of splotches (set to “light” or “automatic”) This is usually more acceptable for animation.


#8

I generally just drop it into the Maya IBL and then add the string options. Although the Maya IBL reverses the image. Something I’ve gotten used to is reversing it before using it.


#9

that’s a very cool hint mate.
It really works with the IBL Node, good to know.

So if i’m comparing the results i get with FG and an HDRI
and the builtin IBL plus HDRI, it’s quite obvious which one give me the better
quality. In fact it’s a huge difference and with the proper setting
it seems that the speed/quality is better balanced compared to the FG method.


#10

Generally speaking it will give you better results than FG alone. It is not always faster (it’s sort of brute force). I will occasionally combine with FG so that I get the indirect lighting as well. Depends on the complexity of what I’m lighting really. Like an interior with the IBL generating outside to inside light, I still need something to fill the room.

But in VFX work, your characters are generally situated in a set. The set data usually includes and HDR of the environment. This means we can light characters with the built-in IBL for integration extremely easily.


#11

Hi !
Can you be more specific David? What do you mean by "Go to the string options:

environment lighting mode
automatic
string " ?
Where are the string options? Input line operations where you can input text with wildcards? If it’s a node, you have to select it somehow…Or do you mean mental ray’s environment lookup node?
I’ve searched through all the documentation, and i cannot find the “new IBL”.I’ve searched on What’s new section, and excepting mia_ciesky and photometric_light, there is no new nodes for mental ray.


#12

You need to open the render globals for mental ray at least once (usually).

Then you can go to the text box at the top right of the Maya tool bar and go to Select By Name.

Input: miD*

Hit enter. This will select the miDefaultOptions. Scroll down and there’s a rollout for String Options. The Add button needs to be hit for each attribute you are going to add. So, if you add all of what I mentioned in the response you would need to click it 5 times.

Then each attribute has three fields:

Name
Value
Type

Fill those in as I have them listed here for whichever ones you want to use.


#13

Hi! Thank you !
I obviously didn’t know that String Options was on miDefaultOptions.Sorry.
I 've used miDefaultOptions before in the previous versions of maya , because it was then the only way to render just FG map.Since 8.5, they made it available in render globals, and i didn’t touch the “hidden” miDefault globals since then.

But that’s a new IBL, or you just alter the built in IBL ? I think that if it was new, it has to be specified somewhere.Cheers!


#14

What these settings do is take the environment attached to your camera and make it the emitting IBL.

This means any environment lookup should work. This includes the Maya IBL since at translation time it becomes the camera environment.


#15

Thank you very very much! I didn’t have a clue.
To be honest, i haven’t used the lookups before.I’ll check that out…I guess Columbo was right: you learn something new every day.


#16

Does the new IBL work with the useBackground-shader? I can´t seem to get any shadows on there.

edit: ok, so the usebackground only catches normal shadows? How would I go about to get the occlusion/shadows from the IBL onto it? Or should I just use a normal occlusion pass?


#17

You might want to try the mip_matteshadow from the production shaders. I do have some strange issues with the built-in IBL if I use it in the beauty, but it can give you occlusion, etc in separate passes.

DJX mip_matteshadow


#18

Interesting. Thanks, I will look into it. Funny how most of my MR questions lead to djx blog :stuck_out_tongue:

btw, what kind of issues do you have? something that renders the beauty unusable?


#19

Sometimes the IBL will reveal the geometry of the matteshadow object and I can’t seem to make it go away every time.


#20

Is the new IBL supposed to work witthout major bugs with mia material transparency?

the reason why I am asking is that I´m working on a pretty complex scene, and was about to add some glasbottles when I noticed that the transperency had no effect. Checking all ray-values, raytracer in the featurestab, checking every possible thing I could think of, turning all IBL-values to high (like transparent shadows and stuff), but the transparency was still not showing. Then I deleted my IBL-setup, and it worked.


#21

I suggest to you to write here:
http://forum.mentalimages.com/forumdisplay.php?82-mental-ray-Maya
Maybe mental images start with some features that work for user.


#22

What IBL setup were you using?

Remember the Maya IBL is an Autodesk feature.

The native IBL feature can use that but it can also use a regular lookup sphere instead. (Pretty much an environment attached to the camera.)


#23

I created a regular IBL setup from render settings, attached my hdr, then used the mr string option script to turn on the hidden IBL features. That´s it. If I delete the ibl-node and add a point light, I can see the transparency work.

I just realised I´ve missed to check something very obvious, create a new scene and create a ibl-setup and a transparent material to see if it is the scene or the ibl that is causing trouble. Will do that later today.

But I guess it must be my scene somehow, an issue like the new ibl not working with transparency surley wouldn´t go unnoticed.


#24

Try exporting. I’ve not had that problem.


#25

How can you control the amount of light ? Through the hdr’s exposure ( in photoshop )?


#26

Try boosting the color gain of the HDRI a bit. The default is one but it can be pushed up.