When I explored the skylighting technique back in October 2000, I first tried to hand craft a dome by hand and soon got tired of starting over every time I had a new idea to explore. I also discovered the constraints of hand crafted domes. This is how I decided to program a small application designed to generate the necessary files to implement this technique for Animation Master. I also decided that the geodesic distribution was the main model I would use for my domes and started with Rick Bono's dome application which I soon modified to generate the data I needed for my skydomes.

The domes generated by the application are available here. I decided to release the model files only instead of the application because the number of geodesic skylights are limited and I did not felt like working on the interface to make it user friendly or foolproof (I did not want to have to support the application). Instead I worked on developing a set of files that allows anyone to easily modify the lighting model through the simple modification of a few files directly inside Animation Master workspace. All the skylight files are available in this Skylights.zip file. For a description of the skylight setups included in this package, see the page Skylight Library.

Here is how it works

Each skylight is composed of 3 files.

A Model file

One model file (.mdl) is simply an array of bones located at geodesic positions on the hemisphere and one bone located at the 0,0,0 llocation which can serve as a target for klieg lights.

There are no splines or patches in this model.

A Light file

One light file (.lit) includes the definition for a default light which is originally set to klieg but can be modified at will by the user.

An Action file

One action file (.act) which replicates the one light file at each bone position in the model file. Each instance of the replicated light is constraint translated to one bone and constraint aimed-at the target bone in the model.

A little random adjustment shift is added to each light position to help get rid of the shadow bandings that can occur in certain circumstances.

As can be observed, only one light is needed for such a setup. This means that any change in intensity, color or any other attributes can easily be fixed by adjusting the lighting parameters in this one single light.

In the downloadable zip file, there are several domes with different number of lights each. The number of lights are indicated in parentheses within the file names. In the example used here, "c2-ico-f2 (20)" is a class 2 icosahedron based of frequency 2 with 20 lights. It is important to use the model, light and action files that match the same number of lights.

Project setup

Import the model file and the light file into your Objects folder in the AM workspace and import the action file into your Action folder.

Drop the skylight model into your choreography and drop the action onto the skylight model. Depending on the size of the scene, it might be necessary to scale the skylight model. Since the scaling operation is done in the choreography, all associated light parameters are scaled at the same time.

Make sure that the skylight model in the choreography is set-up so that it does not receive or cast shadows. This will improve a little the render time if the renderer does not have to check for shadows for this model.

Adjust the light file intensity property to the desired illumination in the scene and render.

Continue to Customizing the Skylight for an exploration of different light type setups or move on to Advanced techniques for Skylights for a review of some nice tricks with skylights.