Proper Way to Draw Rotary Slider Clockwise?

I’d like to draw rotary knobs that go from 5π/4 to -π/4 and travel clockwise. Initially, I was accomplishing this by the following startAngleRadians and endAngleRadians (respectively):
-float_Pi3.0/4.0, float_Pi3.0/4.0

However, that failed the assertion that values be greater than zero.

It seems that float_Pi5.0/4.0, float_Pi11.0/4.0 are giving me the behavior I want without failing assertions. I’m bewildered by that endAngleRadians value, though. It seems to be making a full clockwise circle starting from π/2 then going an additional 3π/4 past that, to get to where I want it. Is this correct? Is this behavior documented somewhere?

Thanks for any insight!
~Tris