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Graph Editor generator for angles works in Radians while the graph editor displays the result in degrees.
Open, Confirmed, MediumPublic


System Information:

Blender Version
Broken: Blender 2.80 Beta (18e5540a48b6) and Blender 2.79 (e290a0b0568e)

Short description of error:
If you use the "generator" modifier in the graph editor for an angle, the generator will work in radians while the graph editor will display the output in degrees.

Exact steps for others to reproduce the error

  1. Open the startup file.
  2. Select the default cube and key frame one of the rotational axis.
  3. Open a graph editor and give the "key framed rotation" and "generator" modifer.
  4. Notice that the results are much greater than what the results should read. This is due to the fact the m in y=mx + c is radians and not degrees while the graph editor works in degrees.

Event Timeline

Sebastian Parborg (zeddb) triaged this task as Confirmed, Medium priority.

Ah.. just after making the D4458 patch I noticed the assignment @Joshua Leung (aligorith)

From discussions with various people over the years, we've all consistently come to the conclusion that all of these things should always be evaluated in radians only, since that's technically how Blender stores + uses all rotation values internally, and it's also what all the math/trig functions in every standard math library work.

It is only for user convenience that we set the "display units" to degrees, to make it easier for artists to use. Technically, everything is really getting evaluated/interpreted in radians everywhere. In the graph editor, we usually apply some conversions to map between the two as necessary when dealing with rotation curves. Perhaps this case is getting skipped when doing the display unit adjustments when drawing the curve, but I'd have to check carefully to know.