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Fix Eagle/Fusion SMD corner radius using pad height instead of shorter side - #581
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qu1ck merged 1 commit intoOct 6, 2026
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…r side Eagle defines SMD roundness relative to the shorter side of the pad (100% gives fully rounded ends), but the parser always used dy. For pads taller than they are wide the radius exceeded half the pad width and the pad was drawn distorted, and lower roundness values were exaggerated. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Eagle defines SMD
roundnessas a percentage of half the shorter side of the pad: 0% is a plain rectangle and 100% gives fully rounded ends. The Eagle/Fusion parser always computed the radius fromdy:That is correct for pads that are wider than they are tall, but for pads taller than they are wide (
dy > dx) the radius exceeds half the pad width. The rounded-rect path then overlaps itself and the pad renders as a distorted shape, while lower roundness values look far rounder than in Eagle.This change uses
min(dx, dy)instead. The unrotated pad size is used, so pad rotation does not affect the result.Testing
Hand-written
.brdwith one package containing these pads, parsed and rendered on master vs this branch:I haven't tested with a real-world Eagle/Fusion design.
Screenshots
Pads from the test board rendered in the generated BOM (front layer, same view for both):
The tall pad at 100% roundness goes from a distorted shape to a proper stadium, and the 50% pad no longer looks fully round. The wide pad and the plain rect are unchanged.
References: EAGLE forum: SMD pad roundness (the shorter side drives the radius), EAGLE help: SMD (100 gives fully round corners).
🤖 Generated with Claude Code