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Line clipping returns empty (invalid?) paths #1424

springmeyer opened this Issue · 2 comments

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It appears that clipping of lines frequently results in paths whose first vertex == SEG_END.

This leads to uninitialized values in our label_positions::centroid/middle_point algorithms. While these algo's recently (as part of the vertex_converters push) return bool for success, our rendering code does not handle this: see #1423

This ticket exists to discuss whether this clipping behavior is correct.

@springmeyer springmeyer referenced this issue from a commit
@springmeyer springmeyer return without rendering if label placement algorithm returns false i…
…ndicating a degenerate geometry - closes #1423 and refs #1424

Note: disabled line clipping for markers in 9539ce9 to avoid the problem described in #1426, which will also avoid this issue from presenting itself for markers (at least). It seems like it might be worth a check in other places we clip lines to avoid undefined behavior and/or simply optimize cases of empty paths.


closing as we can track at #1699

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