[Bf-committers] Degrees, radians, and drivers

[Campbell Barton]

On Wed, Feb 19, 2014 at 11:45 PM, Hadrien Brissaud <hadriscus at gmail.com> wrote:
> Hello,
>
> I hope this is the place to post this, anyway, I have a concern for
> consistency about how rotations are displayed across Blender. I understand
> internally everything i handled in radians, and the drivers use radians
> too, however by default the UI shows rotations as degrees, which becomes
> misleading as soon as you want to use a rotation value in a driver.
> Furthermore I would assume most people use degrees over radians - but I
> have absolutely no number to back this up.
> Since Blender gives the user a choice whether to use degrees or radians,
> drivers should work with one or the other unit depending on which one is
> set in the scene properties. It raises another issue : if the unit of
> choice is changed after creating a rotation driver, the keyframe values are
> suddenly off. They could be converted automatically in this case.
>
> Just a thought. A while ago I spent an entire day trying to figure out what
> was wrong with my rotation driver, so it might be good to clear it up, also
> streamlining the system at the same time.
>
> Cheers,
>
> Hadrien

This sounds like its really a documentation issue, changing how
drivers work based on units (which is really a display & editing
option), is a no-go IMHO.

Understand the kind of frustration you get when running into these
issues but think we just need to make sure how drivers work is made
clear in docs, if there is some place we can make it obvious in the UI
that drivers use radians not degrees, that would be good to do too as
long as its not getting-in-the-way.