arc_to_bulge question

[drmerc]

I'm attempting to convert arcs into polylines using the arc_to_bulge function.
for example:
for e in doc.query("ARC"):
arc_point = ezdxf.math.arc_to_bulge(e.dxf.center, e.dxf.start_angle, e.dxf.end_angle, e.dxf.radius)

The start and end points of the arc_point don't match e.start_point and e.end_point and results in a larger arc than expected.

Is there something I'm missing?

Thanks!

[Timerlen]

This code can be used to check the start point and end point of a circle
from ezdxf.math import Vector
if b.dxftype() == "ARC":
start_point = Vector.from_deg_angle(b.dxf.start_angle, b.dxf.radius)
end_point = Vector.from_deg_angle(b.dxf.end_angle, b.dxf.radius)
s = start_point + b.dxf.center
e = end_point + b.dxf.center
Maybe something is shifted?

[mozman]

FYI: This works only if the extrusion vector == (0, 0, 1), which means the OCS == WCS. An extrusion vector != (0, 0, 1) can also appear if you only work in 2D. CAD applications can use the extrusion vector (0, 0, -1) to change the arc orientation from counter clockwise to clockwise orientation. I found this behavior for arcs in mirrored and then exploded block references.

[Timerlen]

Now I know that I know little. Is there perhaps more extensive documentation somewhere?

[mozman]

The DXF format store angles in degrees, the arc_to_bulge() function requires radians as input.

[drmerc]

That was it! Thank you