Camera turns in oposite direction to track target with track to and copy rotation constraint #83159

New Issue

Vladimir · 2020-11-28T19:55:02+01:00

Vladimir commented

2020-11-28 19:55:02 +01:00

System Information
Operating system: Linux
Graphics card: Intel Haswell

Blender Version
Broken: 2.92
Worked: Never (2.80+)

Short description of error
Camera turns in oposite direction to track target with track to and copy rotation constraint.
2020-11-28_21-40-21.mov

Exact steps for others to reproduce the error
interpolation-bug.blend
Open attached file, compare camera tracking between frames 309 and 310.

**System Information** Operating system: Linux Graphics card: Intel Haswell **Blender Version** Broken: 2.92 Worked: Never (2.80+) **Short description of error** Camera turns in oposite direction to track target with track to and copy rotation constraint. [2020-11-28_21-40-21.mov](https://archive.blender.org/developer/F9401264/2020-11-28_21-40-21.mov) **Exact steps for others to reproduce the error** [interpolation-bug.blend](https://archive.blender.org/developer/F9401271/interpolation-bug.blend) Open attached file, compare camera tracking between frames 309 and 310.

Vladimir commented

2020-11-28 19:55:02 +01:00

Added subscriber: @Wovchick

Vladimir changed title from ~~Unauthorized camera(object) rotation with interpolation frames by X axis location~~ to Unauthorized camera(object) rotation when using interpolation frames by X axis with constraint track to

2020-11-28 20:15:47 +01:00

Vladimir changed title from ~~Unauthorized camera(object) rotation when using interpolation frames by X axis with constraint track to~~ to Unauthorized camera(object) rotation when making interpolation frames by X axis with constraint track to

2020-11-28 20:18:06 +01:00

Vladimir changed title from ~~Unauthorized camera(object) rotation when making interpolation frames by X axis with constraint track to~~ to Unauthorized camera(object) rotation when interpolation frames by X axis with constraint track to

2020-11-28 20:19:37 +01:00

Vladimir changed title from ~~Unauthorized camera(object) rotation when interpolation frames by X axis with constraint track to~~ to Unauthorized turn to 180 degrees Camera when interpolation frames by X axis with constraint track to

2020-11-29 06:51:47 +01:00

Richard Antalik commented

2020-12-07 18:50:05 +01:00

Added subscriber: @iss

Richard Antalik commented

2020-12-07 18:50:05 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Richard Antalik commented

2020-12-07 18:50:05 +01:00

This works correctly when I use copy location on camera instead of parenting. I am not quite sure what "interpolation frames by X axis" means - is it keyframe interpolation?
This looks like bug to me though.

This works correctly when I use copy location on camera instead of parenting. I am not quite sure what "interpolation frames by X axis" means - is it keyframe interpolation? This looks like bug to me though.

Vladimir commented

2020-12-07 20:34:53 +01:00

In #83159#1070293, @iss wrote:
This works correctly when I use copy location on camera instead of parenting. I am not quite sure what "interpolation frames by X axis" means - is it keyframe interpolation?
This looks like bug to me though.

Between keyframes the Blender generating (interpolating) frames and make it incorrect as I seems, the Camera between keyframes sharp rotate to 180 degrees, that it not must be because constraint Track to setted there.

> In #83159#1070293, @iss wrote: > This works correctly when I use copy location on camera instead of parenting. I am not quite sure what "interpolation frames by X axis" means - is it keyframe interpolation? > This looks like bug to me though. Between keyframes the Blender generating (interpolating) frames and make it incorrect as I seems, the Camera between keyframes sharp rotate to 180 degrees, that it not must be because constraint Track to setted there.

Richard Antalik commented

2020-12-08 05:34:26 +01:00

Changed status from 'Needs User Info' to: 'Confirmed'

Richard Antalik changed title from ~~Unauthorized turn to 180 degrees Camera when interpolation frames by X axis with constraint track to~~ to Camera turns in oposite direction to track target with track to and copy rotation constraint

2020-12-08 05:45:37 +01:00

Sybren A. Stüvel commented

2020-12-08 12:14:55 +01:00

Added subscriber: @dr.sybren

Sybren A. Stüvel commented

2020-12-08 12:14:55 +01:00

Changed status from 'Confirmed' to: 'Archived'

Sybren A. Stüvel closed this issue

2020-12-08 12:14:55 +01:00

Sybren A. Stüvel commented

2020-12-08 12:14:55 +01:00

The problem is that, with Euler angles, there are multiple ways in which to reach the same orientation. This means that the Track To constraint has multiple solutions to pick from, and not all of them may be compatible with the world rotation of the Copy Rotation target (in this case, the boat).

A Locked Track constraint will work better in this case (see the attached file). #83159-interpolation-bug.blend

I don't think this is a bug in Blender, but rather a downside of using Euler angles & matrices for the constraint system.

The problem is that, with Euler angles, there are multiple ways in which to reach the same orientation. This means that the Track To constraint has multiple solutions to pick from, and not all of them may be compatible with the world rotation of the Copy Rotation target (in this case, the boat). A Locked Track constraint will work better in this case (see the attached file). [#83159-interpolation-bug.blend](https://archive.blender.org/developer/F9494007/T83159-interpolation-bug.blend) I don't think this is a bug in Blender, but rather a downside of using Euler angles & matrices for the constraint system.

Vladimir commented

2020-12-08 14:27:30 +01:00

In #83159#1070854, @dr.sybren wrote:
The problem is that, with Euler angles, there are multiple ways in which to reach the same orientation. This means that the Track To constraint has multiple solutions to pick from, and not all of them may be compatible with the world rotation of the Copy Rotation target (in this case, the boat).

A Locked Track constraint will work better in this case (see the attached file). #83159-interpolation-bug.blend

I don't think this is a bug in Blender, but rather a downside of using Euler angles & matrices for the constraint system.

I understand! Thank You!

> In #83159#1070854, @dr.sybren wrote: > The problem is that, with Euler angles, there are multiple ways in which to reach the same orientation. This means that the Track To constraint has multiple solutions to pick from, and not all of them may be compatible with the world rotation of the Copy Rotation target (in this case, the boat). > > A Locked Track constraint will work better in this case (see the attached file). [#83159-interpolation-bug.blend](https://archive.blender.org/developer/F9494007/T83159-interpolation-bug.blend) > > I don't think this is a bug in Blender, but rather a downside of using Euler angles & matrices for the constraint system. I understand! Thank You!

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

Camera turns in oposite direction to track target with track to and copy rotation constraint #83159