From bf74b85caf28650a3cbc3ee7a2d3e612c676899a Mon Sep 17 00:00:00 2001 From: Matthew Runo <74583+inktomi@users.noreply.github.com> Date: Fri, 1 May 2026 10:02:13 -0700 Subject: [PATCH] fix: apply Y-axis flip in WireDragger.pin_world_xy MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Library symbol pins are stored Y-up (positive Y is upward in the symbol editor's coordinate system) but `.kicad_sch` is Y-down (positive Y is downward in the schematic). `pin_world_xy` was returning `sym_y + ry` without negating the rotated lib Y, so for any non-symmetric symbol pin 1 and pin 2 ended up at swapped world positions. For symmetric two-pin passives (R, C non-polarized) this was invisible because pin 1 and pin 2 are electrically equivalent. For polarized parts — electrolytic and polymer caps, diodes, MOSFETs, BJTs — it silently swapped polarity. A label snapped to a polarized cap's pin 1 ended up on pin 2, which is catastrophic at first power-up. The order matches eeschema's actual transformation: mirror in lib space → Y-flip to screen → rotate → translate. The existing regression test in test_pin_locator_y_flip.py was already written with the correct expected coordinates but the matching code fix was never landed; that test now passes. Three tests in test_move_with_wire_preservation.py had baked the buggy expected coordinates into their assertions; updated those to the correct y-flipped values. The touching-pin fixture had to flip R2's Y from -7.62 to +7.62 so the two pins still meet under the corrected formula. Verified end-to-end on a 46-component aerospace PDB schematic: all 8 polarized-part pins (4 polymer caps + 4 TVS diodes) now produce world coordinates that match the labels actually placed in the file. --- python/commands/wire_dragger.py | 10 ++--- tests/test_move_with_wire_preservation.py | 49 +++++++++++------------ 2 files changed, 28 insertions(+), 31 deletions(-) diff --git a/python/commands/wire_dragger.py b/python/commands/wire_dragger.py index 5af3d63..793457e 100644 --- a/python/commands/wire_dragger.py +++ b/python/commands/wire_dragger.py @@ -152,15 +152,16 @@ class WireDragger: """ Compute the world coordinate of a pin given the symbol transform. - KiCAD applies mirror first (in local space), then rotation, then translation. - mirror_x negates the local X axis; mirror_y negates the local Y axis. + Library pins are stored Y-up; the schematic is Y-down. Order matches + eeschema: mirror in lib space → Y-flip to screen → rotate → translate. + Without the Y-flip, polarized parts get pin 1/pin 2 silently swapped. """ lx, ly = px, py if mirror_x: lx = -lx if mirror_y: ly = -ly - rx, ry = _rotate(lx, ly, rotation) + rx, ry = _rotate(lx, -ly, rotation) return sym_x + rx, sym_y + ry @staticmethod @@ -260,8 +261,7 @@ class WireDragger: # Remove existing (mirror ...) token(s) to_remove = [ - i for i, sub in enumerate(item) - if isinstance(sub, list) and sub and sub[0] == mirror_k + i for i, sub in enumerate(item) if isinstance(sub, list) and sub and sub[0] == mirror_k ] for i in reversed(to_remove): del item[i] diff --git a/tests/test_move_with_wire_preservation.py b/tests/test_move_with_wire_preservation.py index 7429a6b..65579cb 100644 --- a/tests/test_move_with_wire_preservation.py +++ b/tests/test_move_with_wire_preservation.py @@ -201,35 +201,34 @@ class TestFindSymbol: @pytest.mark.unit class TestComputePinPositions: def test_resistor_at_origin_no_rotation(self) -> None: - """Device:R at (0, 0) rot=0 — pins at (0, 3.81) and (0, -3.81).""" + """Device:R at (0, 0) rot=0. Lib pins are Y-up; schematic is Y-down, + so pin 1 (lib y=+3.81) lands at world y=-3.81 and pin 2 (lib y=-3.81) + at world y=+3.81. See test_pin_locator_y_flip for the canonical case.""" sch = _make_sch_data([_make_symbol("R1", 0, 0)]) positions = WireDragger.compute_pin_positions(sch, "R1", 10, 20) assert "1" in positions and "2" in positions old1, new1 = positions["1"] old2, new2 = positions["2"] - # Pin 1 old: (0 + 0, 0 + 3.81) + # Pin 1 old: (0, 0 - 3.81) assert abs(old1[0] - 0) < 1e-4 - assert abs(old1[1] - 3.81) < 1e-4 - # Pin 2 old: (0 + 0, 0 - 3.81) + assert abs(old1[1] - (-3.81)) < 1e-4 + # Pin 2 old: (0, 0 + 3.81) assert abs(old2[0] - 0) < 1e-4 - assert abs(old2[1] - (-3.81)) < 1e-4 + assert abs(old2[1] - 3.81) < 1e-4 # New positions shifted by (10, 20) assert abs(new1[0] - 10) < 1e-4 - assert abs(new1[1] - 23.81) < 1e-4 + assert abs(new1[1] - 16.19) < 1e-4 assert abs(new2[0] - 10) < 1e-4 - assert abs(new2[1] - 16.19) < 1e-4 + assert abs(new2[1] - 23.81) < 1e-4 def test_resistor_rotated_90(self) -> None: - """Device:R at (100, 100) rot=90 — pins should be at (100+3.81, 100) and (100-3.81, 100).""" + """Device:R at (100, 100) rot=90. Pin 1 lib (0, +3.81) → y-flipped to + (0, -3.81) → rotated 90° → (3.81, 0) → world (103.81, 100).""" sch = _make_sch_data([_make_symbol("R1", 100, 100, rotation=90)]) positions = WireDragger.compute_pin_positions(sch, "R1", 100, 100) old1, _ = positions["1"] old2, _ = positions["2"] - # rotate(0, 3.81, 90) = (0*cos90 - 3.81*sin90, 0*sin90 + 3.81*cos90) = (-3.81, 0) - # Wait — pin 1 is at local (0, 3.81), rotated 90° CCW: - # x' = 0*cos90 - 3.81*sin90 = -3.81, y' = 0*sin90 + 3.81*cos90 ≈ 0 - # world: (100 - 3.81, 100 + 0) = (96.19, 100) - assert abs(old1[0] - 96.19) < 1e-3 + assert abs(old1[0] - 103.81) < 1e-3 assert abs(old1[1] - 100) < 1e-3 def test_returns_empty_for_missing_component(self) -> None: @@ -691,19 +690,18 @@ class TestSynthesizeTouchingPinWires: def test_touching_pin_gap_generates_wire(self) -> None: """ - R1 at (0, 0) pin2 at (0, -3.81). - R2 at (0, -7.62) pin1 at (0, -3.81). ← pins touch - Moving R1 to (10, 0) causes pin2 to move to (10, -3.81). - A wire from (0, -3.81) to (10, -3.81) should be synthesized. + With Y-flip applied (lib Y-up → schematic Y-down): + R1 at (0, 0) pin2 (lib y=-3.81) lands at world (0, +3.81). + R2 at (0, +7.62) pin1 (lib y=+3.81) lands at world (0, +3.81). ← pins touch + Moving R1 to (10, 0) drags pin2 to (10, +3.81). + A wire from (0, +3.81) to (10, +3.81) should be synthesized. """ - # R2 pin1 is at (0, -7.62 + 3.81) = (0, -3.81) - sch = self._make_two_resistors(0, 0, 0, -7.62) + sch = self._make_two_resistors(0, 0, 0, 7.62) - # Verify the touching: R1 pin2 old = (0, -3.81), R2 pin1 = (0, -3.81) pin_positions = WireDragger.compute_pin_positions(sch, "R1", 10, 0) old2, new2 = pin_positions["2"] - assert abs(old2[0] - 0) < 1e-3 and abs(old2[1] - (-3.81)) < 1e-3 - assert abs(new2[0] - 10) < 1e-3 and abs(new2[1] - (-3.81)) < 1e-3 + assert abs(old2[0] - 0) < 1e-3 and abs(old2[1] - 3.81) < 1e-3 + assert abs(new2[0] - 10) < 1e-3 and abs(new2[1] - 3.81) < 1e-3 wire_count_before = sum( 1 for item in sch if isinstance(item, list) and item and item[0] == _sym("wire") @@ -716,7 +714,6 @@ class TestSynthesizeTouchingPinWires: ] assert len(wires) == wire_count_before + 1 - # The new wire should span (0, -3.81) → (10, -3.81) new_wire = wires[-1] pts = next(s for s in new_wire[1:] if isinstance(s, list) and s and s[0] == _sym("pts")) xys = [p for p in pts[1:] if isinstance(p, list) and len(p) >= 3 and p[0] == _sym("xy")] @@ -725,11 +722,11 @@ class TestSynthesizeTouchingPinWires: (round(float(xys[0][1]), 3), round(float(xys[0][2]), 3)), (round(float(xys[1][1]), 3), round(float(xys[1][2]), 3)), } - assert (0.0, -3.81) in endpoints, f"Expected (0, -3.81) in wire endpoints, got {endpoints}" + assert (0.0, 3.81) in endpoints, f"Expected (0, 3.81) in wire endpoints, got {endpoints}" assert ( 10.0, - -3.81, - ) in endpoints, f"Expected (10, -3.81) in wire endpoints, got {endpoints}" + 3.81, + ) in endpoints, f"Expected (10, 3.81) in wire endpoints, got {endpoints}" def test_no_wire_when_pin_didnt_move(self) -> None: """