Animating Lights with Noise

By David Goodman

1. Open a new scene in Max or save your current file and reset. Draw a plane in the Top viewport approximately 250 x 250. The size doesn't really matter since we're just using it as a surface to see the effects of the light.

2. In the Left viewport, create an omni light about 10 grid spaces above Plane01.

3. Select the omni light you just created and right click on it. Go down the list and click on Track View Selected. When the Track View window opens, you will see +Omni01. Click on the +. You will now see +Transform and +Object (Omni Light). Click on the + at +Object (Omni Light). Click on Multiplier, then click on the Assign Controller button . In the Assign Float Controller Window that pops up, select Noise Float.

4. In the Track View window, select and right click on the Omni01 "Multiplier" to bring up the properties window. In the Noise Controller:Omni01/Multiplier window, put a check in ">0" and change the Strength to 2. Select the Perspective view and play the animation. The light should blink erratically like lightning. If you change the Strength values higher, the intensity of the light will increase. If you de-select ">0", the noise controller will let the Light's muliplier value fall below zero and you will get a negative multiplier. This negative value (-1) is the standard method of turning lights off (as in the on/off) controller, but the resulting negative number may give unwanted color to your scene objects when the light is off. For example, if you have an omni light colored bright orange and turn it "off" by changing the multiplier to -1, it will actually emit a bluish light that shows on your scene objects. Putting a tick in the ">0" check box "corrects" this.

5. For the omni to pulse in a different pattern, change the Seed, the Frequency, Fractal Noise and Roughness Values. To envision how this process works, look at the Noise Controller window. Start at the left side of the Characteristic Graph. If you trace your finger to the right along the jagged line, you can imagine that the light's intensity or brightness increases as you travel up the peaks and it dimishes as you travel down the peaks. At any point below the center line (the negative area) the light is effectively off. Checking ">0" does not allow the multiplier to go beneath this line.

6. The Ramp settings: If you want the light to be steady at the beginning and/or end of the animation, set the Ramp In and/or Ramp out values greater than 0. Watch the Characteristics Graph as you do this and see the peaks flatten onto the center line.

7. The Noise Controller can do more than turns lights on and off. You can use to affect an object's PRS Transforms as well. For instance, if you want a camera to shake violently as if in an earthquake, you can assign a noise controller to the camera's position transform. The possiblilities are limitless and I plan to write more tutorials on the subject. As always, experiment to see what you can come up with. Please let me know if this tutorial was helpful to you! Thanks!