Grease Pencil : Points depth inverted

Hi,
I’m bringing up an old post that’s still relevant today: Grease Pencil stroke direction feels inverted by default
This is about the depth of display points of a stroke. The end of the stroke appear behind the beginning of the stroke.
GP_Stoke_direction

I confirm that this behavior is still present in the latest versions of Blender. This is very annoying, especially for a more organic drawing style. It doesn’t feel very natural when drawing.

With the grease pencil V3, wouldn’t this be an opportunity to fix that?
I want to help, even if I’m a newbie in Blender source code. On the other hand, I have very good experience with the API and glsl, and I want to learn.

But first I would like to get the developers’ opinion.
Is this intended behavior? Would you see any harm in changing that?

I did some investigations, and when we switch the direction of the stroke, the depth is displayed correctly (the start of the stroke at the back, the end at the front, like a real drawing).
From what I deduce from how the Grease Pencil works, there are two options:

  • We change the way in which the points are stored in the array at the time of the stroke paint. But it risks impacting performance, and many things downstream.
  • We change the way in which the points are sorted by depth at rendering time.

The second option seems more reasonable to me.
If you think this is a good idea, and you have some ideas to guide me, don’t hesitate!

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I’m glad to see this is not totally forget. Maybe I could try to help too.