From 2d765284f5c93b1095e93a1141a2b5fb7f6bf362 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Mon, 11 Jul 2022 23:27:57 +0200
Subject: [PATCH 1/7] Add grid snapping to grating_coupler_elliptical

(cherry picked from commit fd107da4150d1fb6d9c3d285e7b2918f95d574ee)
---
 gdsfactory/components/grating_coupler_elliptical.py | 2 ++
 gdsfactory/geometry/functions.py                    | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/gdsfactory/components/grating_coupler_elliptical.py b/gdsfactory/components/grating_coupler_elliptical.py
index 4ad45885a4..129cf908d3 100644
--- a/gdsfactory/components/grating_coupler_elliptical.py
+++ b/gdsfactory/components/grating_coupler_elliptical.py
@@ -33,7 +33,9 @@ def ellipse_arc(
     """
     theta = np.arange(theta_min, theta_max + angle_step, angle_step) * DEG2RAD
     xs = a * np.cos(theta) + x0
+    xs = gf.snap.snap_to_grid(xs)
     ys = b * np.sin(theta)
+    ys = gf.snap.snap_to_grid(ys)
     return np.column_stack([xs, ys])
 
 
diff --git a/gdsfactory/geometry/functions.py b/gdsfactory/geometry/functions.py
index 1b88ca484f..c87b10e2ec 100644
--- a/gdsfactory/geometry/functions.py
+++ b/gdsfactory/geometry/functions.py
@@ -165,7 +165,7 @@ def extrude_path(
     spike_length: Union[float64, int, float] = 0,
     start_angle: Optional[int] = None,
     end_angle: Optional[int] = None,
-    grid: float = 0.001,
+    grid: float = 0.005,
 ) -> ndarray:
     """Deprecated. Use gf.path.Path.extrude() instead.
 

From 102708c80dbf62244ff9f154bfc364f169685cac Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Tue, 21 Jun 2022 23:32:12 +0200
Subject: [PATCH 2/7] Change numeric default layers to named layers in port and
 cross_section

(cherry picked from commit b694d6612f0411b6019135b865c478549d5f838f)
---
 gdsfactory/cross_section.py | 2 +-
 gdsfactory/port.py          | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/gdsfactory/cross_section.py b/gdsfactory/cross_section.py
index 0e84d6a910..e15db3f215 100644
--- a/gdsfactory/cross_section.py
+++ b/gdsfactory/cross_section.py
@@ -26,7 +26,7 @@
 Floats = Tuple[float, ...]
 port_names_electrical = ("e1", "e2")
 port_types_electrical = ("electrical", "electrical")
-cladding_layers_optical = ((68, 0),)  # for SiEPIC verification
+cladding_layers_optical = ("DEVREC",)  # for SiEPIC verification
 cladding_offsets_optical = (0,)  # for SiEPIC verification
 
 
diff --git a/gdsfactory/port.py b/gdsfactory/port.py
index 82ce947ce1..e2eb3a7180 100644
--- a/gdsfactory/port.py
+++ b/gdsfactory/port.py
@@ -401,8 +401,8 @@ def port_array(
     ]
 
 
-def read_port_markers(component: object, layers: LayerSpecs = ((1, 10),)) -> Component:
-    """Loads a GDS and returns the extracted ports from layer markers.
+def read_port_markers(component: object, layers: LayerSpecs = ("PORT",)) -> Component:
+    """Loads a GDS and returns the extracted ports from layer markers
 
     Args:
         component: or Component

From 82aba327ef70d0846bcf243f11bddd28841e3e98 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Wed, 13 Jul 2022 01:05:19 +0200
Subject: [PATCH 3/7] Grid snapping and defaults fixes

(cherry picked from commit df950ad25ef202cc77d4107ee8c170c146153089)
---
 gdsfactory/components/bend_circular.py | 2 +-
 gdsfactory/read/from_picwriter.py      | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/gdsfactory/components/bend_circular.py b/gdsfactory/components/bend_circular.py
index e3e0c81fa2..63faa72da5 100644
--- a/gdsfactory/components/bend_circular.py
+++ b/gdsfactory/components/bend_circular.py
@@ -12,7 +12,7 @@ def bend_circular(
     angle: float = 90.0,
     npoints: int = 720,
     with_bbox: bool = True,
-    cross_section: CrossSectionSpec = strip,
+    cross_section: CrossSectionSpec = "strip",
     **kwargs
 ) -> Component:
     """Returns a radial arc.
diff --git a/gdsfactory/read/from_picwriter.py b/gdsfactory/read/from_picwriter.py
index 5cd76892de..6439025336 100644
--- a/gdsfactory/read/from_picwriter.py
+++ b/gdsfactory/read/from_picwriter.py
@@ -79,6 +79,7 @@ def from_picwriter(
         datatypes = poly.datatypes
 
         for polygon, layer, datatype in zip(polygons, layers, datatypes):
+            polygon = gf.snap.snap_to_grid(polygon)
             c.add_polygon(polygon, layer=(layer, datatype))
 
     c2 = Component(c.name)

From 8fac7db8b788118c6d9ca72936d654218db46f81 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Fri, 15 Jul 2022 19:14:28 +0200
Subject: [PATCH 4/7] Fixed default of get_route_from_steps

(cherry picked from commit 66ce68b927db385dbfc2e131d583639ebb02793b)
---
 gdsfactory/routing/get_route_from_steps.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/gdsfactory/routing/get_route_from_steps.py b/gdsfactory/routing/get_route_from_steps.py
index bef39047d8..1aefba4b9e 100644
--- a/gdsfactory/routing/get_route_from_steps.py
+++ b/gdsfactory/routing/get_route_from_steps.py
@@ -4,7 +4,6 @@
 
 import gdsfactory as gf
 from gdsfactory.components.via_corner import via_corner
-from gdsfactory.cross_section import strip
 from gdsfactory.port import Port
 from gdsfactory.routing.manhattan import round_corners
 from gdsfactory.types import (
@@ -21,7 +20,7 @@ def get_route_from_steps(
     steps: Optional[List[Dict[str, float]]] = None,
     bend: ComponentSpec = "bend_euler",
     taper: Optional[ComponentSpec] = "taper",
-    cross_section: Union[CrossSectionSpec, MultiCrossSectionAngleSpec] = strip,
+    cross_section: Union[CrossSectionSpec, MultiCrossSectionAngleSpec] = "strip",
     **kwargs
 ) -> Route:
     """Returns a route formed by the given waypoints steps.

From e69644499eaf1648a1ad0de8db6795e12eceb511 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Wed, 13 Jul 2022 01:05:19 +0200
Subject: [PATCH 5/7] Grid snapping and defaults fixes

(cherry picked from commit 3834ca5fa3767321ed11dadc8a9fb5db67b0b1e4)
---
 gdsfactory/components/bend_circular.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/gdsfactory/components/bend_circular.py b/gdsfactory/components/bend_circular.py
index 63faa72da5..eed3453da0 100644
--- a/gdsfactory/components/bend_circular.py
+++ b/gdsfactory/components/bend_circular.py
@@ -1,7 +1,6 @@
 import gdsfactory as gf
 from gdsfactory.add_padding import get_padding_points
 from gdsfactory.component import Component
-from gdsfactory.cross_section import strip
 from gdsfactory.path import arc, extrude
 from gdsfactory.snap import snap_to_grid
 from gdsfactory.types import CrossSectionSpec

From 5a7abfdb18c77206f071e3cdf26e1ebfebdda552 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Wed, 3 Aug 2022 01:09:31 +0200
Subject: [PATCH 6/7] Read grid size from PDK and grid snapping fixes

---
 gdsfactory/component.py                       |  6 ++++-
 .../grating_coupler_rectangular_arbitrary.py  | 25 ++++++++++---------
 gdsfactory/geometry/boolean.py                |  5 ++--
 gdsfactory/snap.py                            | 14 ++++++++---
 4 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/gdsfactory/component.py b/gdsfactory/component.py
index a90da3582c..9c7e0b2d44 100644
--- a/gdsfactory/component.py
+++ b/gdsfactory/component.py
@@ -1096,7 +1096,7 @@ def write_gds(
         gdspath: Optional[PathType] = None,
         gdsdir: Optional[PathType] = None,
         unit: float = 1e-6,
-        precision: float = 1e-9,
+        precision: Optional[float] = None,
         timestamp: Optional[datetime.datetime] = _timestamp2019,
         logging: bool = True,
         on_duplicate_cell: Optional[str] = "warn",
@@ -1117,6 +1117,10 @@ def write_gds(
                 "overwrite": overwrite all duplicate cells with one of the duplicates, without warning.
                 None: do not try to resolve (at your own risk!)
         """
+        from gdsfactory.pdk import get_grid_size
+
+        precision = precision or get_grid_size() * 1e-6
+
         gdsdir = (
             gdsdir or pathlib.Path(tempfile.TemporaryDirectory().name) / "gdsfactory"
         )
diff --git a/gdsfactory/components/grating_coupler_rectangular_arbitrary.py b/gdsfactory/components/grating_coupler_rectangular_arbitrary.py
index 88b90033c0..72225e6ad1 100644
--- a/gdsfactory/components/grating_coupler_rectangular_arbitrary.py
+++ b/gdsfactory/components/grating_coupler_rectangular_arbitrary.py
@@ -4,7 +4,6 @@
 
 import gdsfactory as gf
 from gdsfactory.component import Component
-from gdsfactory.components.rectangle import rectangle
 from gdsfactory.components.taper import taper as taper_function
 from gdsfactory.types import ComponentSpec, CrossSectionSpec, Floats, LayerSpec
 
@@ -96,18 +95,20 @@ def grating_coupler_rectangular_arbitrary(
     gaps = gf.snap.snap_to_grid(gaps)
 
     for width, gap in zip(widths, gaps):
-        xi += gap + width / 2
-        cgrating = c.add_ref(
-            rectangle(
-                size=(width, width_grating),
-                layer=layer,
-                port_type=None,
-                centered=True,
-            )
+        xi += gap
+        cgrating = c.add_polygon(
+            [
+                (0.0, 0.0),
+                (0.0, width_grating),
+                (width, width_grating),
+                (width, 0.0),
+            ],
+            layer,
+        )
+        cgrating.move(
+            (gf.snap.snap_to_grid(xi), gf.snap.snap_to_grid(-0.5 * width_grating))
         )
-        cgrating.x = gf.snap.snap_to_grid(xi)
-        cgrating.y = 0
-        xi += width / 2
+        xi += width
 
     if layer_slab:
         slab_xmin += length_taper
diff --git a/gdsfactory/geometry/boolean.py b/gdsfactory/geometry/boolean.py
index bd5759cb07..085a6d0299 100644
--- a/gdsfactory/geometry/boolean.py
+++ b/gdsfactory/geometry/boolean.py
@@ -8,7 +8,7 @@
 import gdsfactory as gf
 from gdsfactory.component import Component
 from gdsfactory.component_reference import ComponentReference
-from gdsfactory.types import ComponentOrReference, Int2, Layer
+from gdsfactory.types import ComponentOrReference, Int2, LayerSpec
 
 
 @gf.cell
@@ -19,7 +19,7 @@ def boolean(
     precision: float = 1e-4,
     num_divisions: Union[int, Int2] = (1, 1),
     max_points: int = 4000,
-    layer: Layer = (1, 0),
+    layer: LayerSpec = (1, 0),
 ) -> Component:
     """Performs boolean operations between 2 Component/Reference/list objects.
 
@@ -64,6 +64,7 @@ def boolean(
             elif isinstance(e, Polygon):
                 polys.extend(e.polygons)
 
+    layer = gf.pdk.get_layer(layer)
     gds_layer, gds_datatype = _parse_layer(layer)
 
     operation = operation.lower().replace(" ", "")
diff --git a/gdsfactory/snap.py b/gdsfactory/snap.py
index 30e5f84341..5f51773d32 100644
--- a/gdsfactory/snap.py
+++ b/gdsfactory/snap.py
@@ -1,5 +1,5 @@
 """snaps values and coordinates to the GDS grid in nm."""
-from typing import Tuple, Union
+from typing import Optional, Tuple, Union
 
 import numpy as np
 
@@ -21,13 +21,19 @@ def assert_on_2nm_grid(x: float) -> None:
 
 
 def snap_to_grid(
-    x: Union[float, Tuple, np.ndarray], nm: int = 1
+    x: Union[float, Tuple, np.ndarray], nm: Optional[int] = None
 ) -> Union[float, Tuple, np.ndarray]:
-    if nm == 0:
+
+    if nm is None:
+        from gdsfactory.pdk import get_grid_size
+
+        nm = int(get_grid_size() * 1000)
+    elif nm == 0:
         return x
     elif nm < 0:
         raise ValueError("nm must be an integer tolerance value greater than zero")
-    elif nm == 1:
+
+    if nm == 1:
         y = np.round(np.asarray(x, dtype=float), 3)
     else:
         y = nm * np.round(np.asarray(x, dtype=float) * 1e3 / nm) / 1e3

From 55210a1e2b9ae9e9e432b03f3ba51eac3dd06004 Mon Sep 17 00:00:00 2001
From: bsnyder <b.snyder@psiquantum.com>
Date: Sun, 25 Sep 2022 21:32:04 +0200
Subject: [PATCH 7/7] Added parabolic width_type to taper_cross_section

---
 gdsfactory/components/__init__.py            |  2 ++
 gdsfactory/components/taper_cross_section.py |  7 ++++++-
 gdsfactory/cross_section.py                  |  2 +-
 gdsfactory/path.py                           | 15 ++++++++++++++-
 gdsfactory/types.py                          |  2 +-
 5 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/gdsfactory/components/__init__.py b/gdsfactory/components/__init__.py
index 4cad19ad14..216801bbf3 100644
--- a/gdsfactory/components/__init__.py
+++ b/gdsfactory/components/__init__.py
@@ -220,6 +220,7 @@
 )
 from gdsfactory.components.taper_cross_section import (
     taper_cross_section_linear,
+    taper_cross_section_parabolic,
     taper_cross_section_sine,
 )
 from gdsfactory.components.taper_from_csv import (
@@ -270,6 +271,7 @@
     crossing45=crossing45,
     taper_cross_section_linear=taper_cross_section_linear,
     taper_cross_section_sine=taper_cross_section_sine,
+    taper_cross_section_parabolic=taper_cross_section_parabolic,
     taper=taper,
     taper2=taper2,
     taper_0p5_to_3_l36=taper_0p5_to_3_l36,
diff --git a/gdsfactory/components/taper_cross_section.py b/gdsfactory/components/taper_cross_section.py
index 55b721fa03..e969da462c 100644
--- a/gdsfactory/components/taper_cross_section.py
+++ b/gdsfactory/components/taper_cross_section.py
@@ -12,6 +12,7 @@ def taper_cross_section(
     length: float = 10,
     npoints: int = 100,
     linear: bool = False,
+    width_type: str = "sine",
     **kwargs
 ) -> Component:
     r"""Returns taper transition between cross_section1 and cross_section2.
@@ -22,6 +23,7 @@ def taper_cross_section(
         length: transition length.
         npoints: number of points.
         linear: shape of the transition, sine when False.
+        width_type: shape of the transition ONLY IF linear is False
         kwargs: cross_section settings for section2.
 
 
@@ -42,7 +44,7 @@ def taper_cross_section(
     transition = gf.path.transition(
         cross_section1=gf.get_cross_section(cross_section1),
         cross_section2=gf.get_cross_section(cross_section2, **kwargs),
-        width_type="linear" if linear else "sine",
+        width_type="linear" if linear else width_type,
     )
     taper_path = gf.path.straight(length=length, npoints=npoints)
 
@@ -54,6 +56,9 @@ def taper_cross_section(
 
 taper_cross_section_linear = gf.partial(taper_cross_section, linear=True, npoints=2)
 taper_cross_section_sine = gf.partial(taper_cross_section, linear=False, npoints=101)
+taper_cross_section_parabolic = gf.partial(
+    taper_cross_section, linear=False, width_type="parabolic", npoints=101
+)
 
 
 if __name__ == "__main__":
diff --git a/gdsfactory/cross_section.py b/gdsfactory/cross_section.py
index e15db3f215..e2d7ff6baf 100644
--- a/gdsfactory/cross_section.py
+++ b/gdsfactory/cross_section.py
@@ -19,7 +19,7 @@
 LAYER = TECH.layer
 Layer = Tuple[int, int]
 Layers = Tuple[Layer, ...]
-WidthTypes = Literal["sine", "linear"]
+WidthTypes = Literal["sine", "linear", "parabolic"]
 
 LayerSpec = Union[Layer, int, str, None]
 LayerSpecs = Union[List[LayerSpec], Tuple[LayerSpec, ...]]
diff --git a/gdsfactory/path.py b/gdsfactory/path.py
index 7911ade99c..cb19834a15 100644
--- a/gdsfactory/path.py
+++ b/gdsfactory/path.py
@@ -137,6 +137,15 @@ def sine(t):
     return sine
 
 
+def _parabolic_transition(y1, y2):
+    dy = y2 - y1
+
+    def parabolic(t):
+        return y1 + np.sqrt(t) * dy
+
+    return parabolic
+
+
 def _linear_transition(y1, y2):
     dy = y2 - y1
 
@@ -225,8 +234,12 @@ def transition(
                 width_fun = _linear_transition(width1, width2)
             elif width_type == "sine":
                 width_fun = _sinusoidal_transition(width1, width2)
+            elif width_type == "parabolic":
+                width_fun = _parabolic_transition(width1, width2)
             else:
-                raise ValueError(f"width_type={width_type!r} must be {'sine','linear'}")
+                raise ValueError(
+                    f"width_type={width_type!r} must be {'sine','linear','parabolic'}"
+                )
 
             if section1.layer != section2.layer:
                 hidden = True
diff --git a/gdsfactory/types.py b/gdsfactory/types.py
index 9aca6f5bd4..c22a30c804 100644
--- a/gdsfactory/types.py
+++ b/gdsfactory/types.py
@@ -58,7 +58,7 @@
 ]
 Axis = Literal["x", "y"]
 NSEW = Literal["N", "S", "E", "W"]
-WidthTypes = Literal["sine", "linear"]
+WidthTypes = Literal["sine", "linear", "parabolic"]
 
 
 class Label(LabelPhidl):