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15 February 2007 91,012 views 3 Comments

Adding your own custom passes

So what happens if you want to add in some global illumination, some reflections, or even an occlusion pass? Well, there are various options open to you for you go about adding in these passes.

Firstly, you can always composite these passes in the traditional manner using the various tools that are provided in the FX Tree. This has the disadvantage that it doesn’t present a unified workflow and cannot take advantage of some of the features provided by Post Light

The alternative, is that you can use the companion tool to Post Light, called Post Light Encode.

The Post Light Encode Tool

Post Light Encode allows you to feed in your own lighting information into Post Light via Post Light’s Cache input.

Post Light Encode has three main inputs:

  • Diffuse input

    This input allows you to add passes such as global illumination, final gathering, or any other diffuse type lighting information.

  • Additive input

    This input is for any additive lighting information. You can use this input for passes such as specular, reflections, etc.

  • Cache input

    This input allows you to "daisy chain" Post Light Encode tools together to combine multiple passes into one encoded image.

Post Light Encode does not produce a viewable image, it simply encodes the supplied images into a single image. This encoded image is then able to be fed into Post Light’s Cache input to be properly combined with any lighting from the scene.

For further information about the specially encoded image, please see the previous page.

Occlusion and Shadow Passes

If you have already rendered a shadow or occlusion pass, you can easily use this by plugging it into Post Light’s blue mask input. Just make sure that the Image Input node that you are using to load the pass has its output type set to "RGB", otherwise it will not work properly.

When the occlusion or shadow pass is plugged into the mask input, Post Light will not light the dark areas specified in the pass.

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  • Adam Seeley said:

    Hi, Any idea if this works in Xp 64 bit Soft 2010/2011/2011 sp1.



  • AndyN (author) said:

    Hi Adam,
    That’s a good question. I can’t see a reason why not, but it would need to be recompiled and I’m afraid I don’t have access to a Windows 64bit machine.

    It could only support phong based lighting models so it didn’t catch on as it probably wasn’t flexible enough for most pipelines. Anyway, as a result, I haven’t kept it up to date.


  • Moykul said:

    Brilliant tool! Thank you so much!

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