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Object Tracker Constraint doesn't seem to be working properly
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Description

System Information
Operating system: Windows-10-10.0.17763-SP0 64 Bits
Graphics card: GeForce GTX 660 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 441.66

Blender Version
Broken: version: 2.82 (sub 7), branch: master, commit date: 2020-02-12 16:20, hash: rB77d23b0bd76f
Worked: 2.79 (I can't recall doing an object solve since 2.8)

Short description of error
I've tracked the camera in a shot, gotten a solve, and applied the camera tracker constraint to the camera. Then I also tracked a moving object in the scene and solved for that. In the 3d view, the objects tracking points were a bit too far away from the rest of the scene, so I set the 'object scale' setting down to .1850 to bring it to the correct position. I added a simple cube and gave it an object solver constraint. After selecting the appropriate object and camera in the constraint settings, my cube is much smaller and very close to the camera, nowhere near the tracking markers. In this state, from the camera view, it appears to be moving correctly with the track. To compensate, in the past I would simply move the cube to the location of the object track points, scale appropriately, and it would work perfectly. Now when I move the cube to the points, it doesn't follow them at all, but it still is linked to the camera. I also tried selecting one of the object track points and setting the origin in the solve panel, but that did nothing to affect the cube's position, despite the fact that I've seen that action cause the cube to snap to that location in tutorial videos for older versions of Blender. The only combination of steps that gets me kind of where I want to be is if I reset the object scale back to 1 in the solve panel (moving the track points far away in the 3d view again), then select a tracker and set origin in the solve panel. This moves my cube to the correct location in space, but my track points are still off in the distance for some reason.

Exact steps for others to reproduce the error
Track a 3d camera move using footage, solve camera and apply camera solver constraint. Track separate object in scene, solve for object motion. Create a cube and apply object solver constraint. Try any methods to place the cube in the proper 3d space.

Event Timeline

Philipp Oeser (lichtwerk) changed the task status from Needs Triage to Needs Information from User.Thu, Mar 12, 11:16 AM

Could you provide a minnimal example .blend file demonstrating the issue?
(this ensures we are all looking at the same thing when investigating this, thx)

I tried to create one, but for some reason, without the footage (which I'm not at liberty to share), the blend file kept crashing when I applied the object solver constraint. Might be a separate bug.

Seems related to T74322, but I am not positive enough to mark this as a duplicate.

despite the fact that I've seen that action cause the cube to snap to that location in tutorial videos for older versions of Blender.

@Steve Ernst (steveernst117) do you have a link to any of said tutorials?

I tried to create one, but for some reason, without the footage (which I'm not at liberty to share), the blend file kept crashing when I applied the object solver constraint. Might be a separate bug.

Can you apply the constraint and then upload the file without the footage?

The specific tutorial I had in mind is on the official 'Track, Match, Blend' dvd from 2.6-something or other. But in 2017, I myself made a tutorial on object tracking during which I was able to add the object solver constraint and manually move the cube to the correct location (https://youtu.be/gqUtFF7zBoM?t=1545). For whatever reason, it doesn't work that way in 2.8 so far as I can tell.
*Edit* My current theory is that the camera solve motion and object solve motion are 'overlapping' in some way that they shouldn't be. This tutorial for 2.8 (https://youtu.be/5xPLjDDG_sI?t=148) shows object tracking working pretty much the same way it did in my own tutorial from 2017, but the thing they both have in common is that neither have a moving camera solve.

I just tried appending the camera and the cube with their constraints into a fresh blend file, and that also causes crashes shortly thereafter. I suspect it has something to do with the missing footage file. However, I guess I can always just upload the blend file and the footage will just be missing...maybe everything else will still work.

Ankit (ankitm) changed the task status from Needs Information from User to Needs Triage.Thu, Mar 26, 9:54 AM

Things seem a bit unclear. Could you edit the main post and stick to the template, or even better, file a new bug report with clear steps to redo the bug and the file ?

I agree that this report is a bit unclear.

And it’s not simplified and is too time consuming.
We require the bug reporter to narrow down the problem.
If there are many steps to reproduce the problem, please attach a .blend file saved right before the bug occurs, so only a few steps are needed to trigger the bug.

Please open a new report with the required information.

(About the crash it is better to create another report too).