Reversal read the midpoints after Gradient::reverse had reordered the stops, so each stop
took the wrong segment's midpoint: red-to-blue with its midpoint at 20% reversed to a 50%
midpoint instead of 80%, moving the transition.
Gradient::reverse now mirrors each segment's midpoint with it, so a reversed gradient is the
same ramp the other way round; paint.editGradient's own (wrong) pass is gone, and the SVG
importer's reflect spread, which had a correct copy of the same mirroring, uses it too.
Tests: two- and three-stop gradients with off-centre midpoints sample the same reversed (t vs
1 - t) and come back after two reversals; paint.editGradient reverse turns a 0.2 midpoint into
0.8.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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# ROADMAP.md
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