Add Coating Shader Compound for Autodesk Sogtimage

Coating is really usual in real life. Indeed, it is more unusual in 3D world! Color obtained by coating is a mix of the color of coat and interferences of wavelength, so it’s not so easy to render. I made the choice of simulating and not spectral rendering. It’s easier, faster, and with more artistic controls!

So here is my ‘Add Coating’ Shader Compound for Autodesk Softimage 2011!

It is made for adding nearly any kind of coating! With this compound, you can do:
Colored glaze and varnish,
Antireflect and optical coatings on lens,
Oily Irisation,
Rainbow or color changing glaze…
And so many things!

This ‘Add Coating’ is not made to render real simulation of interference coating. It is made to have a full artistic control over the result. So, you don’t have to know how much thickness should have the coating according to wavelength… Just choose how many rainbows you want and color shift, and you’ll have a nice coated effect!

The shader Compound is easy to use:
First, do your material as usual, using all what you want in your render tree (architectural, phong, complex tree, Gem Dispersion Shader Compound, etc…).
Second, plug your material in the ‘Base material’ input of the ‘Add Coating’ Shader compound, and plug its output to ‘surface’. Voilà! You have coated your material!
Third, play with the many option of the coat to have the desired effect.

This Shader Compound is made for Educational Purpose Only, and it is fully commented. Have a look inside it!

You can also use it ‘as is’ if you need to add some coating.

If you make some pictures with this shader compound, please, don’t forget credits and send me your results. If you have any suggestion for making this compound better, just send me an email!

Quick documentation:
Input:
Base Material: this color is not intended to be use as a color. It’s where you have to plug your uncoated material to add coating to it.
Exaggerate effect: you can make effect more or less visible, more or less exaggerated. Less than one is more correct. Good value is around 0.5.
Disable Coating: switch off the effect of the Shader Compound. It turns it to be just a pass-through. It’s useful if you want to make passes without coating.

Interferences:
Spectral cycles: the number of ‘rainbow’ seen in the coating. Less than one is nice for real coating look, more than one will make a more rainbow effect on object.
Spectral Offset: the way to choose the color of coating you want. Cycle spectral colors to have the one you want at the place you want. It’s just a rainbow color sliding.
Saturation: you can desaturate coating here. When saturation is close or equal to zero, coating is acting like polish on material.

Attenuation:
Fresnel attenuation: at 0, the effect of coating is visible on the entire object, like a lens coating. At 1, just the edges of the material are colored, more like standard coating or colored coating.
Absorption: because of conservation of energy, coating is hiding base material. Absorption makes edges of the object darker (making coating more visible). It is nice to have a ‘deep’ effect on object.

Diffuse Coating:
Light sensibility: Some coatings are reflective and diffusive. Zero means no diffuse, 1 means full diffuse. This is useful for colored and thick coating. It helps also to make coating more visible in case of too few things around to be reflected.
Hardness: diffuse can be real local (light facing diffuse) or on all object. 0 means diffuse is visible on entire object.
Use Tint color: diffuse color is the one of ‘tinted coating’, like pigment include in glaze or coating. It’s the most common case.

Tinted Coating:
Tinted coating: when on, rainbow colors are filtered by the color of tint. It’s a filter color, not a pigment color.
Tint color: the color of tint, or filter color of coating.

Optimisation (for transparent base):
If you plug a transparent material in base material, coating could be very slow because of rendering inside the object in internal and total reflection. When you switch on this option, coating is rendered just on external reflection of object, making it really faster.
It is useful just on transparent base material. I do not recommend it on non transparent object.

Noise:
Noise intensity: you can make rainbow effect more or less noisy. 0 means no noise (default), with perfect rainbow, 1 or more means disturbed coating, like oil.
Noise scale: to adapt the size of noise pattern. The smallest is the scale, the biggest is the pattern.
Use external noise and External noise input: Disable the internal compound noise and take the scalar input as new noise. If you want a more controlled noise (like a logo on your coating…), you can override the internal noise and branch the shader you want here.

Multiple Outputs:
The Add coating compound has multiple outputs. It is useful for another kind of usage.
Instead of using a base material, you can plug the multiple outputs in your material.
For example, connect the ‘reflect color’ to your reflection color, multiply your diffuse color by absorption. On some object, the result will be the same, on other, it would do different effects.

To do:
For next versions, I plan to include a pigment color, acting as a real filter on object. Actually, tinted color does not affect object color.
Also, I’ll add coating specular. Actually, it just add reflect, without specular.
With specular and pigment, it would be possible to emulate thick varnish and glaze.
Multiple coating is actually possible by plugin AddCoating in another AddCoating. I’ll try to make a smarter (and faster) way to do it.
If you have any other idea or need, just ask me!

You can download the compound here: Add Coating Shader Compound

And here are some pictures and videos of coated materials:

AddCoating Shader Compound for Autodesk Softimage from François Gastaldo on Vimeo.

AddCoating Shader Compound Test video from François Gastaldo on Vimeo.

Dispersive Gem Shader Compound updated and FASTER!

I’ve worked on optimization of the Gem Compound Shader.

In the previous version, each ray were rendered 3 times, for R,G and B. It is needed for real accurate dispersion, but it is slow. And even slower when real reflections are added. But we don’t need such accuracy every time. Often, just a good visual effect is needed. So, here is a new version of Gem Shader Compound.

You now have the choice between 3 level of accuracy (and speed) of dispersion. The rendering time is dramatically speeded up!
You can even add reflections and still have a faster rendering time than previous version.

I also added a ‘no dispersion’ option, so you can go even faster if you don’t need dispersion at a time.

This Compound shader is still released for Educational Purpose and is fully commented. You can watch and read how I optimized it to try to get your own compounds faster. If you just want to use it for production, email me first, please.

Quick documentation:
Gem:
Transp Color: The color of the Gem. It should stay not saturated. If you use too much saturated color, you would not see any dispersion effect.

IOR: Base Index of refraction of the Gem. Gems usually have strong IoR, between 1.8 to 2.42.

Dispersion: the variation of IoR between Red and Blue. The stronger this number, the stronger is the effect. I recommend to stay below 0.15.

Metal Gem: when On, the reflection is colored by the Transp Color, giving a metallic look. This effect is not physical, and there is no metal gem in real world. Indeed, the effect is interesting.

Pass:
External Reflection Only: when On, the output returns an alpha ready reflection on external surface of the gem. No transparence is rendering neither ‘total inside reflection’. If you want to composite reflection, you have to make a pass with ‘External Reflection Only’ ON and another OFF.

Accuracy / Speed:
Accuracy: You have 4 ways to render dispersion, from slower to faster:
Full dispersion: it’s the one in the first version of the compound, the slowest one.
Minus back: faster, but secondary dispersion on total reflection is not rendered. I recommend ‘Minus Back’, which is fast and good enough for most usages.
Front only: just the dispersion of the front surface is rendered. It is really faster, and on very complex objects, the difference is not so visible.
No dispersion: No dispersion is rendered! So the Shader is doing usual glass, as other Mental Ray Shaders. It is faster than any dispersion and can be useful if dispersion isn’t needed for a scene…

External reflection Added: Add the External Reflection, but do not render Total Reflection. It is fast enough to be used with any Accuracy.

Full reflection added: Do complete rendering, with Transparency, External, internal and Total reflection. It is the slowest and the most accurate rendering of dispersion. Indeed, it is fast enough to be used with ‘Minus back’ and ‘Front Only’. Using it with Full dispersion can be very very slow and is ok just with very powerful rendering machine.

Usually, on simple objects, you should use the shader compound (few polygons gems) with Full dispersion and External Reflection.
For very complex object, Front only and External Reflection is fast and nice. I strongly recommend to try different accuracies to see what is the best rendering time / accuracy for your need.

You can download the compound here: GemShaderCompound1.4

Jeudis Bordelais 2010, coup d’envoi !

Et oui, c’est reparti ! Nouvelle équipe, nouvelle année, mais toujours le même concept basé sur la bonne humeur, l’ouverture d’esprit et le respect.

Et qu’il est dur de reprendre les photos dans de telles conditions ! J’en ai perdu l’habitude, et ça se voit. Après un ou deux Jeudis, ça ira mieux, mais la reprise fut douloureuse. Il faut dire que les conditions sont à l’opposé du rêve photographique : lumière de ville en quantité minimaliste et pluie étaient au rendez-vous.

Mais comme cela fait du bien de vous revoir à tous ! C’était super ! Vivement le prochain jeudi et encore BRAVO à la nouvelle équipe qui se lance dans cette aventure merveilleuse !

Voilà les photos de la soirée de soutien :

Gem Dispersion Shader Compound

One of the first things we can notice while watching Gems, is that they have high dispersive effect. Dispersion is due to the difference of Index of Refraction between colors, so there is a nice rainbow effect!

A friend tried to have this effect for a gem animation. It’s not so easy, because nothing in Autodesk Softimage let you do it. So, I’ve made this shader compound. It’s just RGB dispersion, with different IoR for R, G, and B. It’s not really fast, but it was enough for the need, and the animation was made!

Although there is no spectral rendering, it’s enough to have a cool visual effect. In fact, it is nice enough to be used in most case, when just the effect is needed, and not spectral accuracy.

As the result is interesting, I decided to release it as Educational Material. It is fully commented, ready to use and to be modified. Open the compound, and play with it!


Note about how to use Gem_Dispersion:
By default, the compound renders just the transparent part of material, without any reflection on surface.
If you want to have reflects, I strongly recommend you to make a new pass with ‘External Reflection Only’ override to ‘On’. Then, simply alpha blend this pass with the one with transp.
The ‘External Reflect Added’ is terribly slow, and I don’t recommend it. This need to be debugged…

If you make some pictures with this shader compound, please, don’t forget credits and send me your results. If you have any question about this compound, just send me an email!

Quick documentation:
Transp Color: The color of the Gem. It should stay not saturated. If you use too much saturated color, you would not see any dispersion effect.

IOR: Base Index of refraction of the Gem. Gems usually have strong IoR, between 1.8 to 2.42.

Dispersion: the variation of IoR between Red and Blue. The stronger this number, the stronger is the effect. I recommend to stay below 0.15.

External Reflection Only: when On, the output returns an alpha ready reflection on external surface of the gem. No transparence is rendering.

External reflection Added: Do complete rendering, with transparence and external reflection. Warning, it is very slow!

Metal Gem: when On, the reflection is colored by the Transp Color, giving a metallic look. This effect is not physical, and there is no metal gem in real world. Indeed, the effect is interesting.

You can download the compound here: Gem Dispersion Shader Compound

To see the animation made by David Mazeau with the help of the Gem Shader Compound: crystal-universe

And here are some pictures of some gems:

Gem Dispersion Shader Compound for Autodesk Softimage from François Gastaldo on Vimeo.

Siggraph 2010 Advance Program

Voici une bonne nouvelle pour tous ceux qui se préparent pour le Siggraph 2010: L'advance program est là !

Il maintenant tant de se plonger dedans et de décider ce que l'on va voir, et surtout ce qu'il ne nous fera pas trop de peine de rater...

Télécharger le tout de suite : Siggraph 2010 Advance Program

Electron Microscope for Autodesk Softimage

Do you like nanotechnologies or microscopy biology? What I really like is the look of those wonderful Electron Microscope images showing the nanoworld. There are noisy, strangely lighted, and seem to be from another world, strange and frightening…

So, I’ve made a shader compound for Autodesk Softimage 2011. The main interest of this compound is, of course, to simulate the electron microscope look, but also to show how to make it ready for passes, compositing, and easy to use.

This Shader Compound is made for Educational purpose, and it is fully commented. It’s really easy to make Electron Microscope look. It’s simply an incidence and an ambient occlusion. But to make this usable and adaptable is not so easy. That’s the goal of this compound. Have a look inside it!

You can also use it ‘as is’ if you need to make some nanopictures.

If you make some pictures with this shader compound, please, don’t forget credits and send me your results. If you have any suggestion for making this compound better, just send me an email!


Quick documentation:
Base lighting:
Light softness: how hard is the ‘lighting’ from electrons. Less softness is a more contrasted picture.
Shadowing distance: contact shadow size, or how far elements are obscuring each other.
Structured noise: Some electron microscope pictures are often noisy. From ‘very noisy’ to ‘extreme softness’, this function added structured noise to your picture, base on lighting. The less noise you have, the slower you are!

Color:
Real Electron Microscope images are black and white. Some of them are colored by post-processing. You can have this ‘colorized look’ by using this color, or switch of colorization and keep original black and white.

Bumpy Noise:
At nano scale, nothing is really flat. So this compound adds bumpy noise on object.
Disable Noise: doesn’t add noise and keep object perfectly flat.
Animated noise: if you choose a very small noise, you can animate it to have a more ‘rough’ picture effect during animation. Don’t use it with large noise!
Noise level: height of the noise. It should stay very small to keep ‘non flat’ effects.
Noise Scale: Size of features of noise. The smaller it is, the biggest are the features.

Bump: If you want to add your own bump to your objet.

Pass generation:
Here are switches for extracting one particular feature of the shader compound:
Total compound is ‘Color * Gradient * Ambient Occlusion’.
You should have just one of them switch on, or none of them. If you switch two, you’ll have to topmost one.

You can download the compound here: Electron Microscope Shader Compound

And here are some pictures and video of my nanoworlds:

Electron Microscope Shader Compound for Autodesk Softimage from François Gastaldo on Vimeo.