Corner pin in 3D space with 3D coordinates?
updated 1 year, 1 month ago 3 Members · 4
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Hello:
I made a 3D animation of a laptop computer in Cinema 4D, with the idea of compositing the contents of the screen later in AE. To that end, I added four dummy objects on the corners of the computer screen in C4D, so that I could import them (along with the camera) into AE as null objects.
So far so good… but once I had my AE project set up, with my camera and my null objects marking the corners of the screen, I realized: and how do I “corner pin” a 3D layer in AE to those four null objects?
(Of course, I could always track the corners of the 3D render, as if it was regular footage, but I’d rather not do it when it’s a CG scene and I have on hand the actual, exact coordinates of the screen in question).
So… uh, is there any way?
You don’t need to use all four points for a corner pin — you can parent the screen to any one of the points, and just use the null’s orientation/position plus the 3D camera to keep the screen in place.
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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you could convert those null’s position to screen space (using the toComp method) so you could apply to the points of the corner pin. But Walter’s solution is more robust because any camera lens effect (such as DOF) will already be applied by default.
Cassius Marques
http://www.zapfilmes.comI did try to use toComp(), but it was giving me nonsensical figures, I don’t know why. But Walter’s solution is much better, and more insightful to boot. So thanks!
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