An assortment of OSL shaders for your perusal

[Rens]

@DaveKW;69723b1

I’m not sure I follow the reason for the rough fresnel. Couldn’t you just increase the ior and decrease the reflection amount, or is it a case of this does it in fewer clicks and/or it’s more physically accurate?

Yes, If you increase the IOR and decrease the reflection amount you’ll get roughly the same, and yes it’s less eyeballing with the shader and you can have varying roughness as well. Plus it calculates the front reflection colour for you.
If you want to set up what I did in the shader yourself you can get a reflection map like Falloff set to Fresnel (or the reflector shader hehe) and place that into the second/white input of a Mix node. Place a VRayColor into the first/black input and set the colour to what you think the front reflection amount will be, roughly. So say RGB 0.04 for a plastic. Now have the glossiness input drive the mix amount. I tweaked the glossiness input a bit in my shader so it’s not linear, but this is roughly the same setup. In the end it’s just a colour blend and not a full per-sample calculation, but it seems to do the trick nicely so far. : )

To explain it a bit more, basically what rough Frensel does is it evens out the reflection amount (the % of light reflected) so that is is less angle dependent. So in most shaders, if you set the IOR and enable Frensel reflections you will have stronger reflections near the grazing angles or side edges of the object, like as in the edges of the sphere example I posted. The front facing reflections will be much lower.
Rough Fresnel evens this out, as when the surface is rougher, the angles get mixed and blended because of all the scratches and bumps on rough surfaces. Basically with a rougher surface you will look at a lot of front facing surfaces mixed into the side facing surfaces and the other way around, because of the micro-detail valleys and mountains (scratches). Summed up with a fully rough surface, this comes down to a close to uniform reflection amount for all angles that is close to the original front facing reflection amount, it gets evened out over all angles, side and front.

In this shader this means I have blended the Fresnel falloff curve (front low, side high) with a single colour that is close to the Fresnel front (low) reflection amount. Or to put it in numbers, when your object reflection is 4% in the front and 100% at the sides, rough Fresnel will blend this to be say 5% in the front and 5% at the sides for a fully rough surface.

@Vizioen

I don’t know if this is possible, I wish there was a shader that makes single sided geometry appear to have actual thickness… kinda like a shader-based Shell modifier. It doesn’t have to be so big as to change the object’s silhouette, just a one-pixel edge that catches the light.

That would be tricky. I had a quick look but you’re pretty limited in OSL when it comes to looking up geometry. A shader similar to the VRayEdgesTex might be able to do that.

@vlado

I remember one time I saw something floating around here which emulates building interios. Imagine you have a high-rise building with thousands of offices behind glass windows. Somewhere I found some sort of shader or sth which generates perspectively correct simplified interiors/rooms behind those glass panels. I can’t find it at the moment, but do you know what I mean?

Yes, I’ve added some features and hope to finish this version in the coming week. Here’s the WIP if you’re interested:
http://www.rensheeren.com/osl/intmaptemp.zip

And this is the thread you mentioned, I think:
http://forums.chaosgroup.com/showthread.php?81727-Interior-mapping-shader&highlight=interior+mapping

@dre4mer

And whats about a Curvature with 3 input Textures Flat,Concave,Convex?

You should sell your shaders, or at least add a donate button to your Page.
I’d be happy to pay a little for them:)

Probably not doable in OSL but I’ll have a look. I won’t be selling these shaders, but I’ll consider a donate button. : )
I started on a blur shader, but it might be very slow, let’s see!

@Ivaylo_Katev

Can you do a decent Color Correction node via OSL? Also +1 for blur node…

Yes I’ve done a CC shader, I’ll upload it sometime next week hopefully.

@joa_grilo

Actually I think I may want something even more important: Texture Bombing!

Sounds interesting! Should be doable, yes.

@Ivaylo_Katev

A procedural texture (or a few) that emulated the weave of various types of fabric would be useful. The clothTex is nice, but only matches a certain type of fabric weave.

That’s a tricky one but would be fun to figure out how to do that. : )

If you want to share what you have on the Disney shader I’d be interested in having a look!