DrcViolation

A single DRC violation.

Returned as part of a DrcResult after running run_drc(). Each violation describes a specific rule failure, including the rule name, affected layer(s), severity, and a bounding box around the offending geometry.

result = run_drc(cell, rules)
for v in result.violations:
    print(f"[{v.severity}] {v.rule_type} on {v.layer}: {v.message}")

Attributes

attributerule_namestr | None

Name of the rule that was violated, or None if the rule was not named.

attributemessagestr

Human-readable description of the violation.

attributeseveritystr

Severity level: "error" or "warning".

attributerule_typestr

Type of the DRC rule that was violated (e.g., "min_width", "min_spacing").

attributelayertuple[int, int]

The (number, datatype) of the primary layer involved in the violation.

attributelayer2tuple[int, int] | None

The (number, datatype) of the second layer, for inter-layer rules (e.g., spacing, enclosure). None for single-layer rules.

attributebboxtuple[tuple[float, float], tuple[float, float]]

Bounding box of the violation as ((min_x, min_y), (max_x, max_y)).

Coordinate frame: top-level (flattened, global) coordinates, the same frame as the final GDS output. Violations raised inside a nested cell are reported at the cell's placed position, not in its local coordinate system. This contract holds for every rule type.

attributecell_namestr | None

Name of the cell containing the polygon that triggered the violation.

Populated for every attributable violation: all per-polygon rules (min_width, min_area, allowed_angles, min_edge_length, self_intersection, max_width, acute_angle, snap_to_grid), all same-layer and cross-layer pairwise rules, and not_inside (set to the inner-layer cell). The only rule type that leaves cell_name as None by design is density, which is a window-level check with no single source polygon.

attributecell_name2str | None

Name of the cell containing the second polygon involved in the violation.

For intra-cell same-layer pairwise violations (both polygons inside the same cell definition), this equals cell_name. For inter-instance or cross-layer pairwise rules, it identifies the other cell. None for per-polygon rules and for cases where the second side is undefined. Examples: an enclosure violation with no outer polygon on the layer, a require_overlap miss (no matching polygon), or a not_inside violation (which unions all outer polygons before testing).

Attributes

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