Re: [fltk.general] Re: filled non-convex polygon disappears when rotated

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Re: Re: filled non-convex polygon disappears when rotated Paul Hahn 08:03 Oct 24 top right image
On Saturday, October 24, 2020 at 9:24:24 AM UTC-5 Ian MacArthur wrote:
Actually... Thinking about this again... I wonder if you need to use fl_begin_complex_polygon & etc. rather than just fl_begin_polygon for concave shapes?

OK I just tried fl_begin/end_complex_polygon and it WORKS! Thanks!
ISTR that is maybe the case, as I think that's where the winding order comes into play.
It's been a while since I've tried this!
BTW my winding order is CCW. I can also go back and try CW winding order with the fl_begin/end_polygon and see if that works.

Probably I missed something in the doco about needing to use fl_begin/end_complex_polygon for this (rotated, concave, CCW) situation. But the interesting thing is that fl_begin/end_polygon did in fact work for this when the rotation angle was zero(???)

From my Fairphone FP3

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