Import: AnimatedTriangle sample model doesn't rotate around a complete circle

[scurest]

AnimatedTriangle has an issue with antipodal quaternions, cf. KhronosGroup/glTF-Sample-Models#185 and KhronosGroup/glTF#1395.

The way I solved this was to

for i in range(1, len(quaternions)):
    if quaternions[i].dot(quaternions[i-1]) < 0:
        quaternions[i] = -quaternions[i]

[julienduroure]

Fixed by 28e731e

[scurest]

There's the same problem for joint animation though.

Rotate.zip

You can probably replace the round-trip through Eulers with that loop too, since round-tripping through Eulers only changes the sign of the quaternion, and that loop fully determines all the signs.

[julienduroure]

ReOpened for bone management

[scurest]

@julienduroure That's still not right.

When you convert quaternions to Eulers or matrices, you lose the information about whether you had q or -q, so flipping signs before you do that is totally useless. It works for that test file only because it happens to go down the if not node.parent branch so it doesn't go through matrices/Eulers. Here's a file that goes down the else branch and still has the problem.

You should do that loop as the last step, to final_rots just before you call fill_fcurves. And I'm pretty sure if you do that you don't need the Euler round-trip.