Error when drawing C shape stroke

[jlampel]

I don't necessarily expect this stroke shape to be supported, but when trying it out I got a freeze and an error:

The extra little straight line at the end of the stroke near the brush was added during the error and was not part of the initial gesture. I started at the bottom left vertex and moved right and up. Doing the same gesture in the opposite direction does not produce the error.

Python: Traceback (most recent call last):
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rfcore.py", line 422, in modal
    RFCore.handle_update(context, event)
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rfcore.py", line 234, in handle_update
    if brush: brush.update(context, event)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rfbrushes\strokes_brush.py", line 179, in update
    self.operator.process_stroke(context, self.stroke, self.stroke_cycle, self.snap_bmv0, self.snap_bmv1)
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rftool_strokes\strokes.py", line 116, in process_stroke
    logic = Strokes_Logic(context, stroke, cycle, snap_bmv0, snap_bmv1, self.span_insert_mode, self.initial_cut_count, RFTool_Strokes.rf_brush.radius)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rftool_strokes\strokes_logic.py", line 234, in __init__
    self.insert()
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rftool_strokes\strokes_logic.py", line 260, in insert
    self.insert_equals()
  File "C:\Users\Jonathan\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\retopoflow\retopoflow\rftool_strokes\strokes_logic.py", line 511, in insert_equals
    bmf = self.bm.faces.new((bmv00, bmv01, bmv11, bmv10))
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: faces.new(...): 0 BMVert has been removed

[vxlcoder]

I haven't implemented C-shapes, yet, but it's not crashing now.

Question: you seem to have edges selected at top and a single vert at bottom-left. Do you think this is how Strokes should determine if it is a C-shape fill?

detecting corners is always a bit tricky, especially with stroke smoothing enabled. But we could potentially detect if one end of stroke hovers the selected edges (top-right) and one end of stroke hovers another vert (bottom-left), which doesn't necessarily need to be selected but could be along an edge strip that connects to an opposite end that was hovered and selected... then we could find the sharpest corner in the stroke and declare it the corner. (so, in other words, first detect how things are connected to selected based on hover first, then find the corner)

[vxlcoder]

commit fdb29be should have this working now!

note: only select either the top edge or the left edge

[jlampel]

Even better than not crashing, this works great!