Relighting is an interesting method that is often used in video post production pipelines.

Given the vector of its surface normal, it is possible to calculate the brightness of each pixel by a pseudo 3D lightning system.

Checkout the demo of SmartReLight!



As the ‘object space’ – or ‘material’ normal’s have to be known, relighting is mostly used within the post process of CG generated images or videos.

It’s a convenient way to archive great lighting and gives the artist most control as he can tune it in real-time without having to re- render the footage for every adjustment.

As you can see from this example, the complete lighting is done by the shader using only a color pass and the object normal’s:

This implementation is fairly simple as it doesn´t support reflections and refractions like Normality , but its fast and does the job – and what better way to get through the last cold days of the year than playing half an hour with Pixel Bender?

It’s also possible to relight already lighted sources to some extend, by not using the color- , but an already phong- shaded pass:

You can download SmartReLight here and the source of the demo including the shader here.

Compiling PB shaders at runtime

Last but not least a short but very interesting story:

Recently I was asked if it was possible to compile a PB shader at runtime.

Given it some thought – why not?

And as it turned out the hell of a chap Nicolas Canasse already took care of that matter.
There is also already an AS3 port by James Ward.

All the best for 2010 !

Microsofts Silverlight has advanced to a level where it´s features and performance get contrastable with flash.

It took mere minutes to port Smart Normal from PixelBender (Hydra) to Silverlights shader Language HLSL (DirectX).
As with Astro, shaders are rendered via software – not the GPU.

The result is roughly comparable with this Flash demo of Smart Normal.

This was not intended to be a performance test but it clearly indicates that Silverlight isn´t inferior when it comes to video, shading or 2,5D.

C# is a mighty language -  easy to pickup for those who are familiar with C++ and working with XAML even feels natural to a Flex developer.

It has to be seen where Open Source, Google, Adobe and Microsoft will take the ‘web 3.0′ but Silverlight definetly has the potential to be a part of that future.
In general, competition is a good thing when it comes to software and the same applies to RIA runtimes…

View the Silverlight Smart Normal demo or download the Smart Notmal shader as HLSL *.fx file.

Hint: If you are looking for a PixelBender Toolkit replacement when working with HLSL try Shazzam.