.. SPDX-FileCopyrightText: 2026 aesc silicon
..
.. SPDX-License-Identifier: AGPL-3.0-or-later

no_angle
========

Flags forbidden edge angles on a layer. By default, every non-orthogonal (not
horizontal/vertical) edge is forbidden; with the ``angle`` param, only edges at one
specific orientation are. Used for IHP's ``Gat.f``: a 45° gate over active area is not
allowed.


Semantics
---------

Run over the tiled merge cache. Typically pointed at an intersection layer (e.g.
``GatPolyOverActiv``) so only the part of the gate actually crossing the channel is
inspected, rather than the whole gate polygon. Each merged region's edges (rectilinear
and oblique alike) are classified by their angle, folded into ``[0°, 180°)``:

- With no ``angle`` param: any edge that isn't within ``tolerance`` degrees of 0° or 90°
  is flagged.
- With ``angle`` set: only edges within ``tolerance`` degrees of that orientation (or its
  180° complement) are flagged — e.g. to forbid *only* 45° edges while tolerating other
  non-orthogonal angles.


Layers
------

One layer — every edge of its merged geometry is checked.


Parameters
----------

``angle``
   Optional. The one forbidden orientation, in degrees. If omitted, every non-orthogonal
   edge is forbidden.

``tolerance``
   Optional, defaults to ``1.0`` (degrees). How close an edge's angle must be to the
   forbidden orientation (or to 0°/90° in the "no angle param" case) to count as
   orthogonal/matching.


Violation markers
------------------

One edge marker per forbidden edge, spanning its full length.


KLayout equivalent
------------------

``layer.edges.with_angle(0, 90, false)`` (non-orthogonal edges) or
``layer.edges.with_angle(angle)`` for a specific forbidden orientation.


Example
-------

.. code-block:: yaml

    - id: Gat.f
      check: no_angle
      layers: [GatPolyOverActiv]
      value: 0.0