# Qlab 2 Custom Geometry



## Chris Chapman (Jan 26, 2015)

I need to map some custom geometry for output on a projector in Qlab 2 (not 3) and don't quite get how you modify the stage. Do you need Quartz Composer to modify the video stage? 

To keep the thread on track, Qlab 3 isn't an option right now due to hardware and OS issues. So dust off your Qlab 2 memory archives and lend a brother a hand, OK?

I'm running off of a MacBook Pro. For testing I haven't set up the projector it needs to talk to. Is it that Qlab doesn't want to modify the default MacBook display? I dunno...


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## Drew Schmidt (Jan 27, 2015)

In an entire video system, Qlab3 or 2 or a Green Hippo or Isadora ... someone has to do work. This just means that _you_ need to do the work prior. You'll have to either use Quartz Composer to corner pin or (and I would suggest this second option if you're on an older system that cannot use Qlab 3) render the videos already pinned. There are a lot of ways to do this; here's one that assumes you have the Adobe suite.

1) Open photoshop. Create a document that is the same size as your second screen. 
2) Next, drag your document to your second screen and hit [F]. This will set your document into full screen (you can toggle this in the menu as well). Then make sure that your navigator is set to 100%. 
3) Fill your entire canvas with black
4) On a new layer, use a white brush to paint the set. Literally. You should see your mouse on the set. Paint the area where you want projections white.

Here you might be able to stop. You've just created a mask. If you don't care about being geometrically accurate, you could make the white area transparent and save the document as a PNG. Then make this your first cue in Qlab on the layer "TOP", then play all your cues on the layer "BOTTOM". The black will cover the area that you dont' want to be seen. The transparent portion will let through the area that you do.

However ... if you need to do corner pinning

5) Pull this document into After Effects
6) Layer the photoshop document on top of your composition and use the Corner Pin effect to adjust the video
7) Turn off the photoshop document and render, render, render, render over night

This will ask your system to do much less work during your show, making it a better solution than Quartz Composer.
You can make adjustments live like you could do with Quartz Composer, making is a worse solution. But if you're careful to get it right the first time, then you'll be fine.


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