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ruddiger52
11-04-2009, 01:25 AM
Is there an equivalent of the max Environment Blur shader in maya?

ruddiger52
11-05-2009, 07:30 PM
On the mia material the interpolation seems to have similar properties but i cant get smooth results

royg
11-05-2009, 07:47 PM
Yes, it's a node called "mia_envblur". Plug it into the Environment slot in your mia material's shading group.

Don't forget to turn on "Single Sample from Environment" in the Interpolation section of your mia material's attributes, otherwise you'll get next to no benefit from the envblur. Set the amount of blurriness (glossiness) via the mia material's glossiness setting. No need to touch any of the settings in the envblur itself.

ruddiger52
11-05-2009, 08:05 PM
ill try it thanks!

joie
11-06-2009, 07:34 AM
And remember also to use that shader only in still images, it will flicker so much in animation.

royg
11-06-2009, 06:37 PM
And remember also to use that shader only in still images, it will flicker so much in animation.Ummm... that's not true at all - or at least is not the fault of the envblur shader.

joie
11-08-2009, 12:19 PM
If you can render an animation with envblur without any flickering on it, please post it.

royg
11-08-2009, 09:51 PM
There is envblur driving the soft reflections on the spheres. Don't see any flicker. NEVER HAVE. If it flickers for you, it's more likely due to a particular HDRI or low FG settings. It is certainly not due to the envblur - although I'd be happily proved wrong: Would you like to post an example of a situation where it renders with no flicker until you add an envblur node to prove it is indeed the envblur causing the flicker?

Saturn
11-08-2009, 09:59 PM
I second that I never had any flicker with mia_env_blur.
Actually this is the opposite.

You may be confused with reflection interpolation mode that cause flicker if you use it on something different than a plane.

joie
11-09-2009, 07:06 AM
Mmm. As far as I know, the envblur node first pixelates the source image and then blurs it. So, I have an animation of a statue where the offended shader flickers, saw it, disconnected it and it worked perfectly, so I guess, it was envBlur failure.

I can't post anything related to that, I'm afraid (NDA issues).

royg
11-09-2009, 06:23 PM
Mmm. As far as I know, the envblur node first pixelates the source image and then blurs it. So, I have an animation of a statue where the offended shader flickers, saw it, disconnected it and it worked perfectly, so I guess, it was envBlur failure.

I can't post anything related to that, I'm afraid (NDA issues).Well, you could still post a test. I whipped mine up in 2 seconds. The point is trying to recreate and repeat the issue.

Anyway, whatever you encountered, I can pretty much guarantee it wasn't the envblur shader. You should perhaps do a few more tests before jumping the gun to make big statements like your original post, because it's just a completely false statement.

The envblur node doesn't exactly simply pixelate then blur the image. It takes an existing environment and converts it into an internal mipmap which it can then do clever lookups in a special coordinate space which resembles normal glossiness but with pretty much an infinite amount of rays. (That sentence was just re-written from Zap's blog ;) Which, of course, is the point of the node - to reduce the grain from environment reflections (instead of having to increase the samples for glossiness). The point is, this will not result in flickering.

I hope I've convinced you that the envblur node is not to blame for the flickering you encountered.

ruddiger52
11-09-2009, 07:26 PM
Hey guys,


I just watched the DT tutorial on this blur node. They say you need to connect the blur node into the environment shader slot on the camera instead of the shading group. Then you need to attach a lookup node into the env blur node and then attach a texture to the lookup node. This is all well and good except that they say this will not blur properly objects in the scene, only the texture applied to the lookup node.

Is the way you are explaining above better for blurring the reflections of an entire scene?? I notice that by applying the the env blur node to the shader group node, you do not need to apply a texture anywhere, which is a good sign to me. Just getting blurring of an environment texture doesn't really do me any good.

By the way I did as explained in this thread and it seems to work. Im just wondering if there are any benefits to doing it as explained in the DT tutorial.

Thanks!!

royg
11-09-2009, 08:09 PM
envblur is solely for getting fast, smooth glossy environment reflections. It doesn't do anything for inter-object reflections, regardless of how you hook it up. You still need to use the samples setting in your mia material to get those smooth, and that is going to affect your render time.

One way around this is to use the max distance setting for reflection (in the mia material) to have the object's reflections fade out the further they are from the reflective surface.

The DT method is when you're just using an image as your environment. My method is when you use an HDRI (via the Image Based lighting section in the render settings) or physical sun & sky. You still can hook up the envblur node to the object's shading group though (or the camera, it doesn't matter - using the shading group means you could potentially have different environments per objects (if you really needed this), using the camera environment slot means it's only one connection so less work but will use the same environment for all environment reflections).

ruddiger52
11-09-2009, 08:17 PM
yeah makes sense. I guess i could do a pano render of the scene and then use that as an environment for the ref pass.

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