Making Smoke With Animated Displacement MapsHash Animation:Master, 1999
Someone on the Hash A:M mail list mentioned that it's possible to apply an animated displacement map to an object, and they posted a sample animation where they used the technique to create a billowing column of smoke. I really liked the effect, but I thought that their smoke looked too hard-edged, and I wanted to see if I could improve on it. Following their general directions I created an animated map and applied it to an object. Then I created a material that faded to transparency at the top an bottom of the object. That helped, but I still thought it needed to be softer, so I made the material anisotropic. Edges that curve away from the camera fade to transparency, while parts that are viewed face-on are opaque. I think it does a pretty good job of simulating the soft yet solid appearance that some plumes of smoke or steam have. Here's a frame from the animated displacement map:
Below is the object that the map distorts. In the animation I scale it up to full size and then keep shrinking and expanding it just a bit.
There are also two earlier variations on the smoke animation: Version 1 and Version 2. Version 1 has some black artifacts that appear in the hilights because of a setting that I messed up when rendering it. |
