Horizontalization of device ports

In the case where the device port needs to be kept horizontal, you can use the Horizontalized class to achieve the horizontalization of the device port, the specific schematic of this function definition is given in gpdk>``routing``>``horizontalized.py``, please refer to the explanatory notes in the horizontalized.py script, the core usage of which is as follows.

Horizontalized

Full script

import math
from typing import List, Optional, Tuple

from fnpcell import all as fp
from gpdk.technology import get_technology
from gpdk.util import all as util



class Horizontalized(fp.PCell):
    """
    Attributes:
        device: device whose ports need to be horizontalized
        bend_factory: Optional, bend waveguide factory
        straight_type: Optional, type of final short straight
        straight_length: defaults to 0.1, length of final short straight

    Examples:
    ```python
    TECH = get_technology()
        device = Horizontalized(device=BendCircular(radius=30, waveguide_type=TECH.WG.FWG.C.WIRE, transform=fp.rotate(degrees=30)))
    fp.plot(device)
    ```
    ![Horizontalized](images/horizontalized.png)
    """

    device: fp.IDevice = fp.DeviceParam()
    bend_factory: Optional[fp.IBendWaveguideFactory] = fp.Param(required=False)
    straight_type: Optional[fp.IWaveguideType] = fp.WaveguideTypeParam(required=False)
    straight_length: float = fp.PositiveFloatParam(default=0.1)

    def build(self) -> Tuple[fp.InstanceSet, fp.ElementSet, fp.PortSet]:
        insts, elems, ports = super().build()
        TECH = get_technology()

        bend_factory = self.bend_factory
        straight_type = self.straight_type
        straight_length = self.straight_length

        PI = math.pi
        HALF_PI = PI / 2

        content: List[fp.IDevice] = [self.device]
        for port in self.device.ports:
            if isinstance(port, fp.IOwnedPort) and not port.disabled:
                port_name = port.name
                port_orientation = fp.normalize_angle(port.orientation)
                final_orientation = None
                if -HALF_PI < port_orientation < HALF_PI:
                    final_orientation = 0
                elif HALF_PI < port_orientation < PI or -PI < port_orientation < -HALF_PI:
                    final_orientation = PI

                if final_orientation is not None:
                    turning_angle = fp.normalize_angle(final_orientation - port_orientation)
                    if fp.is_nonzero(turning_angle):
                        port = util.links.bend(TECH, content, start=port, radians=turning_angle, bend_factory=bend_factory)
                        if straight_length is not None:
                            port = util.links.straight(TECH, content, start=port, length=straight_length, end_type=straight_type)
                        port = port.with_name(port_name)

            ports += port

        insts += content
        return insts, elems, ports


if __name__ == "__main__":
    from gpdk.util.path import local_output_file

    gds_file = local_output_file(__file__).with_suffix(".gds")
    library = fp.Library()

    TECH = get_technology()
    # =============================================================
    # fmt: off

    from gpdk.components.bend.bend_circular import BendCircular
    from gpdk.technology.waveguide_factory import EulerBendFactory

    library += Horizontalized(device=BendCircular(radius=30, waveguide_type=TECH.WG.FWG.C.WIRE, transform=fp.rotate(degrees=30)))
    library += Horizontalized(device=BendCircular(radius=30, waveguide_type=TECH.WG.FWG.C.WIRE, transform=fp.rotate(degrees=30)), bend_factory=EulerBendFactory(radius_min=25, l_max=25, waveguide_type=TECH.WG.FWG.C.WIRE))

    # fmt: on
    # =============================================================
    fp.export_gds(library, file=gds_file)
    # fp.plot(library)

Section Script Definition

Create horizontalized components ports and export layouts

if __name__ == "__main__":
    from gpdk.util.path import local_output_file

    gds_file = local_output_file(__file__).with_suffix(".gds")
    library = fp.Library()

    TECH = get_technology()
    # =============================================================
    # fmt: off

    from gpdk.components.bend.bend_circular import BendCircular
    from gpdk.technology.waveguide_factory import EulerBendFactory

    library += Horizontalized(device=BendCircular(radius=30, waveguide_type=TECH.WG.FWG.C.WIRE, transform=fp.rotate(degrees=30)))
    library += Horizontalized(device=BendCircular(radius=30, waveguide_type=TECH.WG.FWG.C.WIRE, transform=fp.rotate(degrees=30)), bend_factory=EulerBendFactory(radius_min=25, l_max=25, waveguide_type=TECH.WG.FWG.C.WIRE))

    # fmt: on
    # =============================================================
    fp.export_gds(library, file=gds_file)
    # fp.plot(library)

Here, we use the Horizontalized class to horizontalize the port during the transition, where the device parameter input is used to receive the device that needs to be horizontalized, it is the device that will be horizontalized by the port.

straight_type receives the type of straight waveguide used in the horizontalization process. straight_length receives the length of the straight waveguide after horizontalization, and bend_factory receives the curve type of the waveguide. In the following figure, we can see the device after port horizontalization.

GDS Layout