Files
kicad-mcp-server/python/commands/schematic_analysis.py
Eugene Mikhantyev 53564cbc58 fix: check_wire_collisions reports false positives for unannotated components
PinLocator.get_all_symbol_pins resolves symbols by reference designator,
so when multiple components share the same unannotated reference (e.g. "Q?"),
it always returned the first match's pin positions. Every duplicate then
got an identical bounding box, causing a single wire to be flagged against
all N instances instead of only the ones it actually crosses.

Fix: add _compute_pin_positions_direct() that computes absolute pin positions
directly from each symbol's own (at x y rotation) and (mirror ...) data plus
pin definitions fetched by lib_id — no reference-name lookup involved.
Also extend _parse_symbols to capture mirror_x/mirror_y flags.

Add regression test: two "R?" at different positions, wire crossing only
one → must produce 0 collisions against the far-away component.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-22 21:36:50 +00:00

682 lines
24 KiB
Python

"""
Schematic Analysis Tools for KiCad Schematics
Read-only analysis tools for detecting spatial problems, querying regions,
and checking connectivity in KiCad schematic files.
"""
import logging
import math
from pathlib import Path
from typing import Dict, List, Tuple, Optional, Any, Set
import sexpdata
from sexpdata import Symbol
from commands.pin_locator import PinLocator
logger = logging.getLogger("kicad_interface")
# ---------------------------------------------------------------------------
# S-expression parsing helpers
# ---------------------------------------------------------------------------
def _load_sexp(schematic_path: Path) -> list:
"""Load schematic file and return parsed S-expression data."""
with open(schematic_path, "r", encoding="utf-8") as f:
return sexpdata.loads(f.read())
def _parse_wires(sexp_data: list) -> List[Dict[str, Any]]:
"""
Parse all wire segments from the schematic S-expression.
Returns list of dicts: {start: (x_mm, y_mm), end: (x_mm, y_mm)}
"""
wires = []
for item in sexp_data:
if not isinstance(item, list) or len(item) < 2:
continue
if item[0] != Symbol("wire"):
continue
pts = None
for sub in item:
if isinstance(sub, list) and len(sub) > 0 and sub[0] == Symbol("pts"):
pts = sub
break
if not pts:
continue
coords = []
for sub in pts:
if isinstance(sub, list) and len(sub) >= 3 and sub[0] == Symbol("xy"):
coords.append((float(sub[1]), float(sub[2])))
if len(coords) >= 2:
wires.append({"start": coords[0], "end": coords[1]})
return wires
def _parse_labels(sexp_data: list) -> List[Dict[str, Any]]:
"""
Parse all labels (label and global_label) from the schematic S-expression.
Returns list of dicts: {name, type ('label'|'global_label'), x, y}
"""
labels = []
for item in sexp_data:
if not isinstance(item, list) or len(item) < 2:
continue
tag = item[0]
if tag not in (Symbol("label"), Symbol("global_label")):
continue
name = str(item[1]).strip('"')
label_type = str(tag)
x, y = 0.0, 0.0
for sub in item:
if isinstance(sub, list) and len(sub) >= 3 and sub[0] == Symbol("at"):
x = float(sub[1])
y = float(sub[2])
break
labels.append({"name": name, "type": label_type, "x": x, "y": y})
return labels
def _parse_symbols(sexp_data: list) -> List[Dict[str, Any]]:
"""
Parse all placed symbol instances from the schematic S-expression.
Returns list of dicts: {reference, lib_id, x, y, rotation, mirror_x, mirror_y, is_power}
"""
symbols = []
for item in sexp_data:
if not isinstance(item, list) or len(item) < 2:
continue
if item[0] != Symbol("symbol"):
continue
lib_id = ""
x, y, rotation = 0.0, 0.0, 0.0
reference = ""
is_power = False
mirror_x = False
mirror_y = False
for sub in item:
if isinstance(sub, list) and len(sub) >= 2:
if sub[0] == Symbol("lib_id"):
lib_id = str(sub[1]).strip('"')
elif sub[0] == Symbol("at") and len(sub) >= 3:
x = float(sub[1])
y = float(sub[2])
if len(sub) >= 4:
rotation = float(sub[3])
elif sub[0] == Symbol("mirror"):
m = str(sub[1])
if m == "x":
mirror_x = True
elif m == "y":
mirror_y = True
elif sub[0] == Symbol("property") and len(sub) >= 3:
prop_name = str(sub[1]).strip('"')
if prop_name == "Reference":
reference = str(sub[2]).strip('"')
is_power = reference.startswith("#PWR") or reference.startswith("#FLG")
symbols.append({
"reference": reference,
"lib_id": lib_id,
"x": x,
"y": y,
"rotation": rotation,
"mirror_x": mirror_x,
"mirror_y": mirror_y,
"is_power": is_power,
})
return symbols
def _parse_no_connects(sexp_data: list) -> Set[Tuple[float, float]]:
"""Parse all no_connect elements and return their positions as (x, y) tuples in mm."""
positions: Set[Tuple[float, float]] = set()
for item in sexp_data:
if not isinstance(item, list) or len(item) < 2:
continue
if item[0] != Symbol("no_connect"):
continue
for sub in item:
if isinstance(sub, list) and len(sub) >= 3 and sub[0] == Symbol("at"):
positions.add((float(sub[1]), float(sub[2])))
break
return positions
# ---------------------------------------------------------------------------
# Geometry helpers
# ---------------------------------------------------------------------------
def compute_symbol_bbox(
schematic_path: Path,
reference: str,
locator: PinLocator,
) -> Optional[Tuple[float, float, float, float]]:
"""
Compute bounding box of a symbol from its pin positions.
Returns (min_x, min_y, max_x, max_y) in mm, or None if no pins found.
"""
pins = locator.get_all_symbol_pins(schematic_path, reference)
if not pins:
return None
xs = [p[0] for p in pins.values()]
ys = [p[1] for p in pins.values()]
return (min(xs), min(ys), max(xs), max(ys))
def _line_segment_intersects_aabb(
x1: float, y1: float, x2: float, y2: float,
box_min_x: float, box_min_y: float, box_max_x: float, box_max_y: float,
) -> bool:
"""
Test whether line segment (x1,y1)→(x2,y2) intersects an axis-aligned bounding box.
Uses the Liang-Barsky clipping algorithm.
"""
dx = x2 - x1
dy = y2 - y1
p = [-dx, dx, -dy, dy]
q = [x1 - box_min_x, box_max_x - x1, y1 - box_min_y, box_max_y - y1]
t_min = 0.0
t_max = 1.0
for i in range(4):
if abs(p[i]) < 1e-12:
# Parallel to this edge
if q[i] < 0:
return False
else:
t = q[i] / p[i]
if p[i] < 0:
t_min = max(t_min, t)
else:
t_max = min(t_max, t)
if t_min > t_max:
return False
return True
def _point_in_rect(
px: float, py: float,
min_x: float, min_y: float, max_x: float, max_y: float,
) -> bool:
"""Check if a point is within a rectangle."""
return min_x <= px <= max_x and min_y <= py <= max_y
def _distance(p1: Tuple[float, float], p2: Tuple[float, float]) -> float:
"""Euclidean distance between two points."""
return math.sqrt((p1[0] - p2[0]) ** 2 + (p1[1] - p2[1]) ** 2)
# ---------------------------------------------------------------------------
# Tool 2: find_unconnected_pins
# ---------------------------------------------------------------------------
def find_unconnected_pins(schematic_path: Path) -> List[Dict[str, Any]]:
"""
Find all component pins with no wire, label, or power symbol touching them.
Returns list of dicts: {reference, libId, pinNumber, pinName, position: {x, y}}
"""
sexp_data = _load_sexp(schematic_path)
symbols = _parse_symbols(sexp_data)
wires = _parse_wires(sexp_data)
labels = _parse_labels(sexp_data)
no_connects = _parse_no_connects(sexp_data)
# Build set of "connected" positions in mm
connected: Set[Tuple[float, float]] = set()
# Wire endpoints
for w in wires:
connected.add(w["start"])
connected.add(w["end"])
# Label positions
for lbl in labels:
connected.add((lbl["x"], lbl["y"]))
# Power symbol positions (they implicitly connect)
for sym in symbols:
if sym["is_power"]:
connected.add((sym["x"], sym["y"]))
tolerance = 0.05 # mm
def _snap(v: float) -> int:
"""Snap coordinate to grid for O(1) set lookup."""
return round(v / tolerance)
connected_grid: set = set()
for pos in connected:
connected_grid.add((_snap(pos[0]), _snap(pos[1])))
no_connect_grid: set = set()
for pos in no_connects:
no_connect_grid.add((_snap(pos[0]), _snap(pos[1])))
def is_connected(px: float, py: float) -> bool:
sx, sy = _snap(px), _snap(py)
# Check the snapped cell and immediate neighbors to handle edge cases
for dx in (-1, 0, 1):
for dy in (-1, 0, 1):
if (sx + dx, sy + dy) in connected_grid:
return True
return False
def is_no_connect(px: float, py: float) -> bool:
sx, sy = _snap(px), _snap(py)
for dx in (-1, 0, 1):
for dy in (-1, 0, 1):
if (sx + dx, sy + dy) in no_connect_grid:
return True
return False
locator = PinLocator()
unconnected = []
for sym in symbols:
ref = sym["reference"]
# Skip power symbols, templates, and empty references
if sym["is_power"] or ref.startswith("_TEMPLATE") or not ref:
continue
pin_positions = locator.get_all_symbol_pins(schematic_path, ref)
if not pin_positions:
continue
pin_defs = None
for pin_num, pos in pin_positions.items():
px, py = pos[0], pos[1]
if is_no_connect(px, py):
continue
if is_connected(px, py):
continue
if pin_defs is None:
pin_defs = locator.get_symbol_pins(schematic_path, sym["lib_id"])
pin_name = pin_defs.get(pin_num, {}).get("name", pin_num)
unconnected.append({
"reference": ref,
"libId": sym["lib_id"],
"pinNumber": pin_num,
"pinName": pin_name,
"position": {"x": round(px, 4), "y": round(py, 4)},
})
return unconnected
# ---------------------------------------------------------------------------
# Tool 3: find_overlapping_elements
# ---------------------------------------------------------------------------
def find_overlapping_elements(
schematic_path: Path, tolerance: float = 0.5
) -> Dict[str, Any]:
"""
Detect spatially overlapping symbols, wires, and labels.
Args:
schematic_path: Path to .kicad_sch file
tolerance: Distance in mm below which elements are considered overlapping
Returns dict: {overlappingSymbols, overlappingLabels, overlappingWires, totalOverlaps}
"""
sexp_data = _load_sexp(schematic_path)
symbols = _parse_symbols(sexp_data)
wires = _parse_wires(sexp_data)
labels = _parse_labels(sexp_data)
overlapping_symbols = []
overlapping_labels = []
overlapping_wires = []
# --- Symbol-symbol overlap (O(n²)) ---
non_template_symbols = [s for s in symbols if not s["reference"].startswith("_TEMPLATE") and s["reference"]]
for i in range(len(non_template_symbols)):
for j in range(i + 1, len(non_template_symbols)):
s1 = non_template_symbols[i]
s2 = non_template_symbols[j]
dist = _distance((s1["x"], s1["y"]), (s2["x"], s2["y"]))
if dist < tolerance:
entry = {
"element1": {"reference": s1["reference"], "libId": s1["lib_id"],
"position": {"x": s1["x"], "y": s1["y"]}},
"element2": {"reference": s2["reference"], "libId": s2["lib_id"],
"position": {"x": s2["x"], "y": s2["y"]}},
"distance": round(dist, 4),
}
# Flag power symbol pairs specifically
if s1["is_power"] and s2["is_power"]:
entry["type"] = "power_symbol_overlap"
else:
entry["type"] = "symbol_overlap"
overlapping_symbols.append(entry)
# --- Label-label overlap ---
for i in range(len(labels)):
for j in range(i + 1, len(labels)):
l1 = labels[i]
l2 = labels[j]
dist = _distance((l1["x"], l1["y"]), (l2["x"], l2["y"]))
if dist < tolerance:
overlapping_labels.append({
"element1": {"name": l1["name"], "type": l1["type"],
"position": {"x": l1["x"], "y": l1["y"]}},
"element2": {"name": l2["name"], "type": l2["type"],
"position": {"x": l2["x"], "y": l2["y"]}},
"distance": round(dist, 4),
})
# --- Wire-wire collinear overlap ---
for i in range(len(wires)):
for j in range(i + 1, len(wires)):
w1 = wires[i]
w2 = wires[j]
overlap = _check_wire_overlap(w1, w2, tolerance)
if overlap:
overlapping_wires.append(overlap)
total = len(overlapping_symbols) + len(overlapping_labels) + len(overlapping_wires)
return {
"overlappingSymbols": overlapping_symbols,
"overlappingLabels": overlapping_labels,
"overlappingWires": overlapping_wires,
"totalOverlaps": total,
}
def _check_wire_overlap(
w1: Dict[str, Any], w2: Dict[str, Any], tolerance: float
) -> Optional[Dict[str, Any]]:
"""
Check if two wire segments are collinear and overlapping.
Returns overlap info dict or None.
"""
s1, e1 = w1["start"], w1["end"]
s2, e2 = w2["start"], w2["end"]
# Check horizontal collinearity
if abs(s1[1] - e1[1]) < tolerance and abs(s2[1] - e2[1]) < tolerance:
if abs(s1[1] - s2[1]) < tolerance:
# Both horizontal, same Y
min1, max1 = min(s1[0], e1[0]), max(s1[0], e1[0])
min2, max2 = min(s2[0], e2[0]), max(s2[0], e2[0])
if min1 < max2 and min2 < max1:
return {
"wire1": {"start": {"x": s1[0], "y": s1[1]}, "end": {"x": e1[0], "y": e1[1]}},
"wire2": {"start": {"x": s2[0], "y": s2[1]}, "end": {"x": e2[0], "y": e2[1]}},
"type": "collinear_overlap",
}
# Check vertical collinearity
if abs(s1[0] - e1[0]) < tolerance and abs(s2[0] - e2[0]) < tolerance:
if abs(s1[0] - s2[0]) < tolerance:
# Both vertical, same X
min1, max1 = min(s1[1], e1[1]), max(s1[1], e1[1])
min2, max2 = min(s2[1], e2[1]), max(s2[1], e2[1])
if min1 < max2 and min2 < max1:
return {
"wire1": {"start": {"x": s1[0], "y": s1[1]}, "end": {"x": e1[0], "y": e1[1]}},
"wire2": {"start": {"x": s2[0], "y": s2[1]}, "end": {"x": e2[0], "y": e2[1]}},
"type": "collinear_overlap",
}
return None
# ---------------------------------------------------------------------------
# Tool 4: get_elements_in_region
# ---------------------------------------------------------------------------
def get_elements_in_region(
schematic_path: Path,
x1: float, y1: float, x2: float, y2: float,
) -> Dict[str, Any]:
"""
List all wires, labels, and symbols within a rectangular region.
Args:
schematic_path: Path to .kicad_sch file
x1, y1, x2, y2: Bounding box corners in schematic mm
Returns dict: {symbols, wires, labels, counts}
"""
min_x, max_x = min(x1, x2), max(x1, x2)
min_y, max_y = min(y1, y2), max(y1, y2)
sexp_data = _load_sexp(schematic_path)
symbols = _parse_symbols(sexp_data)
wires = _parse_wires(sexp_data)
labels = _parse_labels(sexp_data)
locator = PinLocator()
# Symbols: include if position is within bounds
region_symbols = []
for sym in symbols:
if not sym["reference"] or sym["reference"].startswith("_TEMPLATE"):
continue
if _point_in_rect(sym["x"], sym["y"], min_x, min_y, max_x, max_y):
entry = {
"reference": sym["reference"],
"libId": sym["lib_id"],
"position": {"x": sym["x"], "y": sym["y"]},
"isPower": sym["is_power"],
}
# Include pin positions
pin_positions = locator.get_all_symbol_pins(schematic_path, sym["reference"])
if pin_positions:
entry["pins"] = {
pn: {"x": round(pos[0], 4), "y": round(pos[1], 4)}
for pn, pos in pin_positions.items()
}
region_symbols.append(entry)
# Wires: include if ANY endpoint is within bounds
region_wires = []
for w in wires:
s, e = w["start"], w["end"]
if (_point_in_rect(s[0], s[1], min_x, min_y, max_x, max_y) or
_point_in_rect(e[0], e[1], min_x, min_y, max_x, max_y)):
region_wires.append({
"start": {"x": s[0], "y": s[1]},
"end": {"x": e[0], "y": e[1]},
})
# Labels: include if position is within bounds
region_labels = []
for lbl in labels:
if _point_in_rect(lbl["x"], lbl["y"], min_x, min_y, max_x, max_y):
region_labels.append({
"name": lbl["name"],
"type": lbl["type"],
"position": {"x": lbl["x"], "y": lbl["y"]},
})
return {
"symbols": region_symbols,
"wires": region_wires,
"labels": region_labels,
"counts": {
"symbols": len(region_symbols),
"wires": len(region_wires),
"labels": len(region_labels),
},
}
# ---------------------------------------------------------------------------
# Tool 5: check_wire_collisions
# ---------------------------------------------------------------------------
def _compute_pin_positions_direct(
sym: Dict[str, Any], pin_defs: Dict[str, Dict]
) -> Dict[str, List[float]]:
"""
Compute absolute schematic pin positions for a symbol instance directly from
its parsed position/rotation/mirror data and pin definitions in local coords.
Unlike PinLocator.get_all_symbol_pins, this does NOT do a reference-name
lookup in the schematic, so it works correctly when multiple symbols share
the same reference designator (e.g. unannotated "Q?").
KiCad transform order: mirror (in local coords) → rotate → translate.
"""
sym_x = sym["x"]
sym_y = sym["y"]
rotation = sym["rotation"]
mirror_x = sym.get("mirror_x", False)
mirror_y = sym.get("mirror_y", False)
result: Dict[str, List[float]] = {}
for pin_num, pin_data in pin_defs.items():
rel_x = float(pin_data["x"])
rel_y = float(pin_data["y"])
# Apply mirroring in local symbol coordinates
if mirror_x:
rel_y = -rel_y
if mirror_y:
rel_x = -rel_x
# Apply symbol rotation
if rotation != 0:
rel_x, rel_y = PinLocator.rotate_point(rel_x, rel_y, rotation)
result[pin_num] = [sym_x + rel_x, sym_y + rel_y]
return result
def check_wire_collisions(schematic_path: Path) -> List[Dict[str, Any]]:
"""
Detect wires passing through component bodies without connecting to their pins.
For each non-power, non-template symbol:
1. Compute bounding box from pin positions (shrunk by margin).
2. For each wire segment, test intersection with the bbox.
3. If intersects but no wire endpoint matches a pin → collision.
Returns list of collision dicts.
"""
sexp_data = _load_sexp(schematic_path)
symbols = _parse_symbols(sexp_data)
wires = _parse_wires(sexp_data)
locator = PinLocator()
margin = 0.5 # mm margin to shrink bbox (avoids false positives at pin tips)
pin_tolerance = 0.05 # mm
collisions = []
# Pre-compute per-symbol data
symbol_data = []
for sym in symbols:
ref = sym["reference"]
if sym["is_power"] or ref.startswith("_TEMPLATE") or not ref:
continue
# Get pin definitions by lib_id (works regardless of reference designator,
# so unannotated components with duplicate "Q?" references are handled correctly).
pin_defs = locator.get_symbol_pins(schematic_path, sym["lib_id"])
if not pin_defs:
continue
# Compute absolute pin positions directly from this symbol's own position/rotation,
# bypassing the reference-name lookup in PinLocator (which always finds the first
# symbol with a given reference, breaking for unannotated duplicates like "Q?").
pin_positions = _compute_pin_positions_direct(sym, pin_defs)
if not pin_positions:
continue
xs = [p[0] for p in pin_positions.values()]
ys = [p[1] for p in pin_positions.values()]
min_x, min_y, max_x, max_y = min(xs), min(ys), max(xs), max(ys)
# Expand degenerate dimensions (pins in a line) to approximate body size
min_body = 1.5 # mm minimum half-extent for component body
if max_x - min_x < 2 * min_body:
cx = (min_x + max_x) / 2
min_x = cx - min_body
max_x = cx + min_body
if max_y - min_y < 2 * min_body:
cy = (min_y + max_y) / 2
min_y = cy - min_body
max_y = cy + min_body
# Shrink bbox by margin
min_x += margin
min_y += margin
max_x -= margin
max_y -= margin
# Skip degenerate bboxes (single-pin or very small after shrink)
if max_x <= min_x or max_y <= min_y:
continue
pin_set = set()
for pos in pin_positions.values():
pin_set.add((pos[0], pos[1]))
symbol_data.append({
"sym": sym,
"bbox": (min_x, min_y, max_x, max_y),
"pin_set": pin_set,
})
# Test each wire against each symbol bbox
for w in wires:
sx, sy = w["start"]
ex, ey = w["end"]
for sd in symbol_data:
bx1, by1, bx2, by2 = sd["bbox"]
if not _line_segment_intersects_aabb(sx, sy, ex, ey, bx1, by1, bx2, by2):
continue
# Check if either wire endpoint matches a pin of this symbol
endpoint_matches_pin = False
for px, py in sd["pin_set"]:
if (abs(sx - px) < pin_tolerance and abs(sy - py) < pin_tolerance):
endpoint_matches_pin = True
break
if (abs(ex - px) < pin_tolerance and abs(ey - py) < pin_tolerance):
endpoint_matches_pin = True
break
if not endpoint_matches_pin:
sym = sd["sym"]
collisions.append({
"wire": {
"start": {"x": sx, "y": sy},
"end": {"x": ex, "y": ey},
},
"component": {
"reference": sym["reference"],
"libId": sym["lib_id"],
"position": {"x": sym["x"], "y": sym["y"]},
},
"intersectionType": "passes_through",
})
return collisions