I am looking to use a bone as a “slider” to control the rotation of another bone. When the slider is at the lowest end of it’s range the target bone will not be rotated. And when the slider is at the top end of its range the target bone will be rotated 90 degrees.
I understand drivers and constraints fairly well. But the only control I have for rotating the bone is a quaternion. I would like to, say, control the rotation around the X axis with a driver but I don’t see how I can do that.