Mocha-Nuke CornerPin 4-point track workflow in flame?

I am using constantly Mocha 4-corner tracks in Nuke (CornerPin node) to track a still frame into a shot. (or a part of it)
I track a shot in Mocha, export a CornerPin node and paste it into Nuke.
The four corners track/distort the image throughout the shot. On the reference frame you keep the transform TO and the transform FROM values identical (no distortion).

I would like to so the same in Flame.
I export from Mocha the 4-corner tracks and load them into the 4-corners of a bilinear. I can do the same trick like in Nuke in flame and copy the tracking data to the UV channels and only keep the reference frame values on one frame. Then I also don’t have any distortion.
The problem is the the 4-corners are the boundary of the frame in flame. In Nuke the four corners are just transformation data as you can see on the screenshot.

I guess a workaround in Mocha could be to place the 4-corners on the corners of the image resolution.
Is there a way to in flame to copy the workflow from Nuke?


Best, Daniel

After you copy the animation to the UVs, you should be able to switch to the Move UV/Vertex tool using shift-u and then scale the vertices of the UV to create a larger canvas so that your image isn’t being clipped by the edges of the surface.

Instead of applying the tracking data to the verts of your perspective surface, apply the tracking to your UV points. Make sure to use 4 corners →

Then you can do some stuff–>

When you want to pin it back, apply the tracking to the verts instead.


Edit: Someone will likely point out that the smoother way is exporting your tracking as a gmask tracer with axis from Mocha, loading that setup into Flame and using the axis to distort and undistort a surface in action as an axis has a built in invert toggle.


Thank you both, I will try that all out tomorrow.

Best, D

Under Surface>Extrapolation, there is a button called Crop. You want that turned off.

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@toodee I reread your post and I think @ytf has the actual answer you were looking for setting a single frame reference to extend beyond the geometry extents.

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Yes, I think the “Crop” button is doing the trick! This button reminds me of the Project3D node in Nuke. Every time I forget about the enabled crop :slight_smile:

Thanks a lot all of you.

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