jefken,
hatch and solid fill using different techniques.
For hatch a repeated pattern is used and stenciled with the contour.
The direction and order of contour entities doesn't matter here.
But for solid fill a flood fill algorithm is used. For this the direction and order of entities is relevant.
And the algorithm has to detect what is outside and inside and this seems to be buggy.
I had the idea to use polylines for the contour, but this failed too. The result is different, but still invalid.
So if you need solid fill for your drawing I recommend dellus' advice.
Armin
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