Dynamic overhang speed does crazy things not what expected

[freakydude]

Description of the bug

I did a series of overhang tests at different speeds to determine how slow I had to print to get a certain overhang (angle) to print cleanly.

Then I wanted to teach the slicer the dynamic overhang speed. Unfortunately, I immediately realized that it does change speeds, but individually and here in connection with bridges it makes total nonsense.

First of all I would suggest to:

• define a Bridge as: "0 to X % Overhang AND straight lines from end to end". Give the user a parameter to define X. (for consistency maybe as degree)
• define an Overhang as: "0 to Y % Overhang AND not a Bridge (curved lines or more then X % Overhang)". Give the user a parameter to define Y. (for consistency maybe as degree)

I would expect:

• the first layer of bridges is fully recognized as a bridge and then assumes the speed for the bridge (80). Instead, the 3 lines to the right and left are perimeters, for which the dynamic speed then partially acts - for the 5 lines in the middle, the bridge speed.
• speed for 0% overlap and bridge speed should be an exclusive either/or - in any case, it is not clear how they relate to each other, neither in the description, better nor in the surface.
• the blue/yellow lines are obviously calculated by the dynamic overlap speed. The lines are 100% planar to the XY plane. A change between 60mm/ and 10mm/s (i.e. between 0%, 25% and 50%) is completely implausible.
• the overhang speed changes abruptly on one and the same line, which is absolutely horizontal between 0/50% and 25% speed. This cannot be possible at all.
• there is no (extra) distance between red + blue/yellow, it is a closed area (there is one in the slicer and that is how it is printed)

If you add the Benchy to the same project, for example - or an overhang test and take a closer look at it, you will also notice that the current implementation makes no sense at all and only looks good at first glance.

I am attaching the project with all settings and also the object again individually.
I suspect that the issue will get lost here again, but I hope that someone can really take a closer look and correct it.

Many thanks
freakyDude

Project file & How to reproduce

crazy-dynamic-overhang-speed-settings.zip

Checklist of files included above

• Project file
• Screenshot

Version of PrusaSlicer

2.7.1-win64

Operating system

Windows 11

Printer model

Sidewinder X2 with Klipper