New Processing Components: Illumination, Shadow, Reflect

I was looking a bit into Genetica recently, and - while I don't like it too much compared to FF - I noticed it has some quite handy and fast pseudo 3D processing nodes called Illumination, Shadow, Reflect and Refract.

Now, Refraction we already have, and - obviously - FF has surface type filters to simulate indirect illumination and reflection (and indirect 'shadowing' from the HDRI lighting) most excellently. Direct illumination and 'hard' shadows are missing, though.

What would make Illumination, Shadow and Reflect components appealing? You could use them INSIDE of filters (inside simple filters, most importantly), and be able to further process their pseudo-3D results as opposed to having those effects applied after the fact in the result node. They are similar to the Refraction component in that - apart from the image map - they would require an additional input, a height map, to define a pseudo 3D surface that would be used to calculate the illumination, shadow and reflection respectively. Illumination and Shadow would also require the user to input the hemispherical location of a point or direct light.

Of course, I have absolutely no clue how hard this would be to integrate into FF's procedural architecture, but the existence of the Refraction component gives me hope. Besides, how cool would this be...

Some simple examples how these nodes are used in Genetica:

Some more examples:

Adding Lights...

Small correction:

Illumination and Shadow only have ONE input in Genetica, the heightmap (which is always the red channel). Makes sense.

Yeah, those are a MUST!

Kinda defeats the purpose of passing a height map to the surface renderer but here's an "illuminate" filter...



Light.ffxml

I pretty much nailed the illumination effect in FF. Unfortunatly its pretty slow and there's a serious bug that will delay its release for a while. Anyway here's a preview...

Controls...


Height Map...


Rendered Effect...

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uberzev wrote: I pretty much nailed the illumination effect in FF

Looking nice so far. Please post the filter!

Hmmm. No word from the devs?

And I wasn't even the only one who thought this one was just sooooo cool! *sigh*

As for Reflect -- FF would need tools/components to produce procedural spherical maps / cube maps to produce the environment for the component. And we dropped that idea because procedural environments don't look as good as high-quality real-world HDRIs.

i'm not even going to pretend i understand all this, but i'll throw my newb question/suggestion into the fray anyways... wouldnt more custom or hdri filters do the job... at least somewhat? i mean, who says a custom hdri cant have multiple light sources?

and that raises another question, at least for me, how much work would it be for FF itself to make, rather than just import, these custom hdri's?

Craig

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Crapadilla wrote: Direct lighting. Compared to HDRI lighting this certainly feels like a step back in quality.

FF already has the code for direct lights, there's just no UI for that. We'll get back to this in future versions.

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Crapadilla wrote: Hard Shadows.

Very expensive to render.

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Crapadilla wrote: Toon Shading.

This is very important for a 3D renderer, but I'm not sure if this is important to a texture tool. Plus, the toon shading can be done via a separate filter type, or by adding curves to remap diffuse and specular functions (however that can significantly slow down the rendering).

Low Dynamic Range, i.e. a regular bitmap

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Vladimir Golovin wrote: FF already has the code for direct lights, there's just no UI for that. We'll get back to this in future versions.

...

Well, it dawns on me that the Genetica examples I gave above were probably not suited too well for discussing the non-obvious and experimental uses that I had in mind for these proposed components. But since introducing a second layer of shading/lighting into FF makes little sense indeed and would certainly confuse users, I'm gonna have to rest my case.

Rest in peace, beloved Illumination/Shadow components...

Also, I would like to correct, that there are some significant technical difficulties with that

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Crapadilla wrote: the toon shading can be done via a separate filter type

Well, I wouldn't mind a third filter type called 'toon filter' with its own specific lighting tab and renderer. Might be very nice to achieve all sorts of stylized surface effects.

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Crapadilla wrote: Hey, uberzev! This bug that prevented you from releasing your 'illumination technique' , has it been fixed in the release version? I'm asking because I still think you were on to something there which hasn't been explored at all. Maybe you could release it as a snippet?

Actually it was fixed a few versions ago. I just sort of forgot about it.

Its essentially an emboss. What it lacks is the ability to make the light come from a more overhead position.

Illuminate.ffxml

The top shows the height map. The left is what my illuminate snippet renders, and at the right what a more sophisticated illumination would provide.

Alright, that explains what I am seeing there.

I was under the impression that FF always rounded fractional values of sliders to two digits of precision internally. If that rounding is just happening for the display of these values, then count me in complaining on that one. This is definitely a "Bad Thing™"!

The good thing about this: I've learned something new about FF...

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Crapadilla wrote: Hard Shadows. Without a doubt, these would still be interesting IMHO, even in HDRI renders. I would maintain that this might be a feature worth integrating into the surface filter render engine.

I have created quite working cheat to create hard shadows on flat surface. All you need is heigtmap and you just need to displace hard shadow with it. Only limitation is that shadows can't be too long.

My example filter does not have shasow direction, but it can be implemented. Theoretically shadows could be also be rendered to non flat surface as log as surface is smooth and not too steep.

Filter can be found here:
http://www.filterforge.com/filters/2275.html



Those shadows work also for more complex height fields than just raindrops that are used in that filter.

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The biggest problem with faking hard shadows this way is that they are disconnected from the actual lighting happening in the result node. If you tweaked the lighting, the shadows should change accordingly, but with faked shadows you'd have to introduce additional controls to do that.

Yes. That is offcourse problem (not in my filter because it uses own lightning inteface) which could be rounded by allowing filter to have information about lingning controls.

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Also, 'real' shadows would pick up the 'ambient' color of the environment, leading to greater realism.

I don't understand why faked shadows could not do this?

And I am npt trying to say that this fake makes idea of real shadows obsolete. It does not... Nut still usable way to create hard shadow if they are not implememted in FilterForge.

I'd like to be able to specify a profile gradient as env. map from inside the filter. (Instead of having to import an exr or pfm)

Dilla, I think that something along that line is a really good idea....allowing more customization over existing lighting.....and could allow filters to be submitted with outside HDRIs.....

Maybe done under something like an environment profile....

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uberzev wrote: Please add at least the illumination component

No! Just give us illumination gradients, and we're fine!