[cgbeige]

I'm trying to make a simple driven key to make a light approximation setup for Maya lights and Maxwell but I can't get the emitter Watts or Lumens values to be keyable in the Set Driven Key options. Is this possible? or is there an Expression I can use to do the same thing?

[msantana]

Couldn't find the link right now, but somebody (I think Mike Verta) made a video or a tutorial a while ago precisely about this.

I was able to dig out some file that I had and I could recall the example somewhat. The problem if I recall correctly is that the emitter variable in the Maxwell shader doesn't allow any negative numbers as input, so it won't allow directly to be modified as a driven key. However there is a workaround:

• 1. Create a light (Mental Ray or Maya)
  2. Animate its intensity (and since this variable is between 0 and 1 you can link it to the emitter)
  3. Link the intensity of the Maya light to the emitterWatts variable of your MXM shader.

You can then animate the Maya light any way you want, for example you can put an expression that oscillates (say a sine function of time), link that to the intensity and then link that light to the Maxwell emitter property as outlined above.

In the example I worked out, I created an expression of time, linked that to the intensity of a maya ambient light, and then linked that to the Maxwell material emitter properties. It still works in maya 2009.

Good luck.

[cgbeige]

thanks - that worked. I should have tried the basic connection editor first, I guess.