Qlab and the Power of Quartz

Several times now in this column or while speaking, I have mentioned my affection for Figure53’s Qlab software, in particular the feature set for video that was so greatly expanded by the latest version. Specifically, I think the greatest tool that this new version has given us is the ability to make Quartz Composer output more accessible—more useful—in a cue-based playback situation.

There seems to be a little confusion about, or aversion to, Quartz for some reason. Maybe it’s the seemingly alien and perplexing nature of its object-oriented interface. Maybe it’s a reluctance to purchase yet another software package for what seems like a limited use.

Here’s the thing: Quartz Composer is free (well, with a Mac, which just might be that last reason to convert for all you PC lovers out there). And it’s easy. The software comes packed with so many sample compositions that getting started is fun and simple. If that isn’t enough for you, the inter-tubes are loaded with pre-built Quartz compositions and tutorials for building your own.

Quartz is flexible, and, because it is integral to the OS X system, it runs extremely fast. Getting to know it and love it will very nearly infinitely expand Qlab’s utility for video. My favorite application for it is something that, up until recently, was the domain of more expensive media servers: mapping video to a 3D object.

For the Bill T Jones/Arnie Zane Dance Company’s latest production, Fondly Do We Hope, Fervently Do We Pray, programmer Dallas Nichols and I were brought in to help implement Qlab for projection on a giant ellipsoidal curtain that circuits the entire stage. Janet Wong’s design for the video envisioned it mapped to the surface of the curtain. In order to accomplish this, we used Qlab, Quartz and a plug-in for Quartz called Kineme3D (available here). We very simply created a 3D elliptoid the same proportion as the curtain on its elliptical track. Then, using Kineme3D, we could rotate and manipulate the object to match the orientation of the FOH projector. By publishing the input and attaching the Quartz renderer file to each Qlab video cue via dragging and dropping, we could map each video cue’s content to the surface without needing to make changes to the source artwork. That way, when the show changes venues the production staff can make simple changes to the Quartz file and be done with focus from the new projector position.