OpenEXR Integration with Renderelements in newer builds

[studioDIM]

It is not quite a fair comparizon, since the RPF stores more information than EXR. RPF stores multilayer information where you can have, for example, multiple z-values for a single pixel for the different objects in that pixel whereas EXR is limited in this regard and would store only a single z-value for that pixel.

Oh, i stand corrected.
I always saw layers, and never thought much of them
Now i see the light
Cheerio Vlado.

Lele

[panthon]

Oh, i stand corrected.
I always saw layers, and never thought much of them
Now i see the light
Cheerio Vlado.

Lele

Now enligthen us!

What are layers and sublayers for inverted phase subpixels for? Any practical application?

[instinct]

erm...maybe feature lists and marketing ? :P

seriously i guess it helps a lot in doing proper DOF calculations in post.

Thorsten

[panthon]

seriously i guess it helps a lot in doing proper DOF calculations in post.

Thorsten

How does it help? And how do u setup this kind of layers approach?

[studioDIM]

i cannot find ANY info on layers in rpfs, honestly.

Even though, with objects, in max, one can choose to "render hidden objects" hidden, that is, by the object in front of them
And layers MIGHT come handy in there, whereby layer one has, say, the Zdepth for the front object, and layer 2 has the Z for the one at the back, where the pixels ARE overlapping, but for a number of reasons (i cannot quite figure out) are needed.
I am thinking of maybe billboards, where there are troubles with opacity, and layers might help.

Lele

[vlado]

Aside from helping for DOF, the layers allow you to correctly isolate an object in combustion, for example.

Imagine that you want to brighten up an object in the scene. Now imagine that you have a pixel where this object is in front of another one. The subpixel layers allow you to decompose the pixel into the contribution of each object, brighten up only the object that you need, and then assemble the pieces again into the new pixel value.

Without this sub-pixel information, the program doesn't know exactly what to do. It will either brighten the whole pixel, or leave the whole pixel unchanged, which will result in a halo around your object.

Best regards,
Vlado

[panthon]

Aside from helping for DOF, the layers allow you to correctly isolate an object in combustion, for example.

Imagine that you want to brighten up an object in the scene. Now imagine that you have a pixel where this object is in front of another one. The subpixel layers allow you to decompose the pixel into the contribution of each object, brighten up only the object that you need, and then assemble the pieces again into the new pixel value.

Without this sub-pixel information, the program doesn't know exactly what to do. It will either brighten the whole pixel, or leave the whole pixel unchanged, which will result in a halo around your object.

Best regards,
Vlado

Thanks, I am going to look into it and how to implement it in our current workflow asap.

[studioDIM]

Now i am confused for good

I can see layers other than 1 are often sub-pixel in rpfs (mainly black, with outlines at most, and visually broken at that), but you're saying that i would need to use the additional layers to correctly pull an objectID-based mask for instance?

Or i got it wrong?

Lele

[studioDIM]

Mmmmh, ok i see what you mean, Vlado, about AA issues and edges.

I find it very convoluted, though, for little change in most situations.
Also, i can see in the manual of combustion that it should support multilayer RPFs (all that i can render from max IS multilayer) on import, allowing to choose what layer has to be imported and how, but it doesn't work on 4.03 (no dialog box ever pops up).
So i have to manually duplicate a comp layer, add the operator to show the GBuffer (coverage in my case), set it to show layer two, extract the object id i want, and do a composite alpha arithmetic to "clean up" the AAsed edges.

I would point out that an alpha erode of half a pixel most times does it.

Or did i really get this one wrong?
Panthon, any clue?

Lele

[panthon]

Currently, i dont see any practical way to use it in combustion. I dont even know how to setup it in max in order to distribute objects in layers.

[studioDIM]

ah THAT is easy: render

Layers are automatic, there is no intervention possible...

Lele

[instinct]

memo to myself: include multiple z´buffer channels in openEXR writer :P

Still wonder how the rpf saver accesses the additional layer(s)...There is only one z-buffer i though...hmm....Reading Alert! :P

Thorsten

[studioDIM]

the confusing thing is that they call them LAYERS.
Well they ain't.
They are just, err, heum, well, yes, LAYERS , but not in a Photoshop sense.
That is: the Z IS one and one only.
On layer two you will find something like a combination of Coverage and Z, or in other words, the subpixel, AAsed edges of the Zbuffer. On layer three you might find more bits (the higher the layer number, the lower the amount of infos in it, i keep finding out) of SP detail, and so on.

And again, if anyone finds anything at all on this stuff, i'd be glad to dive into it as well...

Lele

[panthon]

And again, if anyone finds anything at all on this stuff, i'd be glad to dive into it as well...

Lele

Not much info about it, huh?
It must be for a good reason...

[studioDIM]

discreet combustion = polite fart ?

Lele