Is the camera moving, or locked down? What’s currently behind the window? Is it light or dark?
If it’s locked down, you might be able to simply mask out the window and position your 3D render. Duplicate the masked layer, invert the mask (so you get the window only), raise it above the BG plate and CG render in the stack, and change its transfer mode to something like screen.
If the camera is moving, you may be able to track the window (Mocha-AE would be brilliant for this) and repeat as above, or you may have to solve the camera in 3D (such as with SynthEyes or the Foundry’s CAMERATRACKER). You’d need to export this 3D data both to your Max camera and your AE camera.
Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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