This week at our meetup we got a chance to hang out at HDMG’s studio. It offered a dark space for the projector and a huge area to project on the cyc wall. No one had trouble seeing this time! We also saw several new faces and had good conversations.
First we got down to business showing off the new website and our Slack group. If you haven’t heard about the new site, well… here we are. If you haven’t joined the Slack group, or aren’t sure what Slack is, head over to this page for more info and to request an invite.
Then we got going with our expressions presentations. The key takeaways were:
- Expressions can save you time by easily linking one animated property to another.
- With enough R&D, you can reduce complicated animations to just a few keyframes.
- Tool Farm offers a good starter expression class from Harry Frank.
- Dan Eberts’ site Motion Script offers a lot of expression examples and detailed explain actions of how it all works.
Christopher Levin showed us a simple but great example of how to link animations together then offset them in time for a trailing effect using
valueAtTime(). He also used layer references to automatically get values from the previous layer in the comp. You can download his project to pick it apart.
Next up was Paul Conigliaro giving a very brief overview of how to think about building expressions. The bottom line was to think about expressions as taking some kind of input, doing some hand crafted magic, and spitting out a new value for your property. One example was to auto-roll a wheel based on its width and x-position. Piggy-backing off Chris, he showed how to loop shape or mask path animations using two methods: A slider &
valueAtTime(), and using a modulus operator (
%). You can take a look at the full project file including examples not shown.
Closing out the presentations was Dean Rockne showing off his slick whiteboard video rig. To save time on production of multiple videos, he developed a rig using expressions to animate the position of a precomp containing a 3D rendered hand holding a marker. By pointing the precomp to 3 layer controls (start, end, and middle containing the drawing of the shapes), the precomp cycles through its different animations of the hand raising, lowering, and wiggling as it reveals the vector drawing below.