Line-Symbol-Templates for simple- and marker-line with arrowheads #64555
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… line with arrowheads
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| </data_defined_properties> | ||
| </layer> | ||
| </symbol> | ||
| <symbol alpha="1" clip_to_extent="1" force_rhr="0" frame_rate="10" is_animated="0" name="arrowheads markerline" tags="Showcase" type="line"> |
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Can you set addedVersion here too? Otherwise the auto-upgrade logic won't kick in.
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Why's the start trim here different to the end trim? Can you explain why those values need to be different? |
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Thanks!
It's a compromise. Because the marker starts at the start-trim position, but does not end exactly at the end-trim position. First, when the last element before the gab is a gap, the end trim appears longer than it is (here with starttrim 3 and endtrim 3 - would be the same with endtrim 2.1): 
On endtrim 2 it would still be another marker, so the end-gap is small, but looks better. 
Still a problem, when the line is not a whole element in the end. Here again an endtrim of 2: 
So one have to find the best value so there are not too large gaps and still not too close at the end marker. In the example of this PR we have an element of size 6 and an interval of size 6. We have a starttrim of 8 and an endtrim of 5 what appeared to me the best solution (starttrim minus half of the marker size). But honestly I'm not 100% convinced anymore. But I can do more evaluations on Monday. |
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Simple line with arrowheads and marker line with arrowheads in the category "Showcase".
Screencast.From.2026-01-15.16-33-49.mp4
This PR depends on #64548 because the use of the trim option on marker lines.