Hi,
After analyzing your repro case, I came to the conclusion that the shape of your spline is what creates the issue. For a Bezier to approximate perfectly a circle, and as far as I know, you need a Control Point every quarter of circle. Your half circle only has 2 CPs.
I modified your scene to use a circle spline that has a CP every 90°. I used the Range parameters of the Shape Extrusion module to use only half of the circle. In this case, even with default values and non cached spline, the gap is not visible.
I attached the scene.
Does this solve your issue?
Have a nice day.
After analyzing your repro case, I came to the conclusion that the shape of your spline is what creates the issue. For a Bezier to approximate perfectly a circle, and as far as I know, you need a Control Point every quarter of circle. Your half circle only has 2 CPs.
I modified your scene to use a circle spline that has a CP every 90°. I used the Range parameters of the Shape Extrusion module to use only half of the circle. In this case, even with default values and non cached spline, the gap is not visible.
I attached the scene.
Does this solve your issue?
Have a nice day.
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