v3.4.2: More accurate change percentages

A minor revision that makes change percentages more accurate when copper is drawn differently between revisions.

Released October 20, 2026. Auto-update will deliver v3.4.2 to existing installs over the next few hours.

Comparing an Eagle export with the same board from Fusion 360 could report copper layers as 20 to 30% changed, even when the overlay showed almost no difference. Eagle fills copper pours with many thin strokes, while Fusion writes them as filled areas. GerbDiff drew those thin strokes too faintly, so the pour itself counted as changed. GerbDiff now takes a closer look at layers like these before reporting a percentage, and the same board reads well under 1%.

Thanks to the user who reported this and shared files to reproduce it.