Single extrusions print slow and noisy

[Dreide]

Occasionally, single extrusions which fill internal thin walls (see Advanced->Thin wall behavior) are printed rather slow and with a creaking noise. When I analyzed how a cylindric wall is sliced (diameter 20mm), I found that one perimeter was made of 128 segments - fine. But the single extrusion for filling the gap in the wall was made of 515(!) segments. What is this high resolution good for? This number is actually not even consistent; it seems to change depending on what has been sliced before, so something is off. Anyway, the segments of the single extrusion are often so short that the motor step resolution becomes an issue. For example, the calculated angles between segments can appear much bigger due to round-off errors than they actually are, possibly triggering unnecessary deceleration in order to get around the putative corner; similarly, there are quite a number of segments for which the extruder position, in terms of whole-numbered motor steps, wouldn't change, which also triggers a full deceleration down to jerk speed.

I consider this a slicer bug, especially given that it is not even consistent. However, besides getting this fixed, it might be good to have a setting which allows the user to control the minimal segment length (maybe "minimum change in extruder position per segment"?).

[PhillipM]

Yes, it causes issues on some slow 8/16 bit boards - the skirt generation does the same thing, makes them far too high resolution and results in some machines stuttering as they can't process it fast enough.

[FalloutBe]

This issue still persists.
Can this please be looked into?
For example, our Ultimaker 2+ extended slows down on most single extrusions due to this problem.


If I go through the G-code like by line, I can see that the segment length on the (external) single extrusion is around 0.1mm long, which is very tiny