AE CC 2017, mocha Pro 5.5.1, Mac OS Sierra 10.12.3
I've read the FAQ, watched multiple tutorials and still stumped. I must be missing a fundamental concept in mocha or AE, and I am admittedly new to more advanced concepts in both. I have tried doing this with cut & paste workflow in mocha AE as well as mocha Pro and nothing has worked.
I have footage that where I am replacing the head of a running individual with a Photoshop 2D image. Portions of the footage have foreground obstructions so I need to mask those and knock out appropriate portions of the 2D image over the life of the clip. The obstructions are also moving and intersect the 2D image for 20 frames or so in different portions of the clip. For the purposes of trying to solve this I have just concentrated on one area, a thrown flag that passes in front of the video area I am superimposing with the 2D graphic.
Tracking works great. I create a track for the head, including a tracking cut out layer track for the thrown flag so that it doesn't interfere with my main track. I export the tracking for the head by cut & paste, link to my null linked to my 2D image, and it works as advertised. But no joy when I create shapes that I will use as a mask for knockouts for the flag obstruction. Reload my footage layer in mocha, I move to a starting frame and create an X-spline around flag, then track forward, adjusting spline position and shape (the flag changes shape as it flutters) along the way. Then I stop when safely out of the area of obstruction, set in and out points as relevant. I export mocha AE shape data to clipboard, using either visible layers or selected layer - simple because there is just the one shape.
In AE, playhead on first frame of comp, I create my solid above the 2D image layer. Everything goes black as expected. I move the playhead to the first frame for my flag shape. I then paste the shape data into the solid layer, and see my "flag shape" when I twirl down. I trim back the solid to the flag in and out points. Everything under the solid remains the solid color, which seems weird. When I look at the parameters, I see opacity is set to 0%. I manually set this to 100% and now see the underlying video clips, the 2D image, and my starting shape. So OK, I set the image layer to use the solid layer as an alpha inverted track matte. Play through the clip, nothing happens, 2D image obscures the flag. So I undo setting the track matte, and the shape reappears on screen. Hit play, and I see that the shape never moves, never changes shape, to match what I had done in mocha.
When I look at the actual shape data, it looks like it contains values changing over time, but I am a n00b so can't tell. I should also note that I started first with a round trip clip from premiere to AE to mocha and back. I thought maybe this was an offset issue, so that I started using in an out points in the mocha import window (which caused other issues with "cannot set frame because"), then I just started with AE and importing the footage direct instead of direct link from Premiere, and finally after much back and forth I just trimmed the clip to the i/o I wanted and created an image sequence to eliminate potential issues and started the process from scratch with AE to mocha. And still no joy. Also note that I have ensured that the sizes (1280x720) and frame rates (29.97 for video, 30 for the image sequence) are the same between mocha and AE.
There may be a different workflow with the mocha plugin, but I would like to get the cut & paste but right first in mocha pro in case all I ever have to work with is mocha AE. Please point out my misconceptions or bonehead actions and save me from myself so that I can at least have a joyful weekend making this work.