Static Materials with intricate shapes

This module contains a (currently rather small) collection of objects with a shape that is more intricate than a basic cuboid.

fdtdx.objects.static_material.Cylinder

Bases: StaticMultiMaterialObject

A cylindrical optical fiber with configurable properties.

This class represents a cylindrical fiber with customizable radius, material, and orientation. The fiber can be positioned along any of the three principal axes.

Attributes:

Name	Type	Description
radius	float	The radius of the fiber in meter.
material	Material	The material properties of the fiber.
axis	int	The principal axis along which the fiber extends (0=x, 1=y, 2=z).
partial_voxel_grid_shape	PartialGridShape3D	The shape of the voxel grid in grid units.
partial_voxel_real_shape	PartialRealShape3D	The shape of the voxel grid in physical units.
color	tuple[float, float, float]	RGB color tuple for visualization (default=LIGHT_GREY).

Source code in src/fdtdx/objects/static_material/cylinder.py

@extended_autoinit
class Cylinder(StaticMultiMaterialObject):
    """A cylindrical optical fiber with configurable properties.

    This class represents a cylindrical fiber with customizable radius, material,
    and orientation. The fiber can be positioned along any of the three principal axes.

    Attributes:
        radius: The radius of the fiber in meter.
        material: The material properties of the fiber.
        axis: The principal axis along which the fiber extends (0=x, 1=y, 2=z).
        partial_voxel_grid_shape: The shape of the voxel grid in grid units.
        partial_voxel_real_shape: The shape of the voxel grid in physical units.
        color: RGB color tuple for visualization (default=LIGHT_GREY).
    """

    radius: float = field(kind="KW_ONLY")  # type: ignore
    material: Material = field(kind="KW_ONLY")  # type: ignore
    axis: int = field(kind="KW_ONLY")  # type: ignore
    partial_voxel_grid_shape: PartialGridShape3D = frozen_private_field(default=UNDEFINED_SHAPE_3D)
    partial_voxel_real_shape: PartialRealShape3D = frozen_private_field(default=UNDEFINED_SHAPE_3D)
    color: tuple[float, float, float] = LIGHT_GREY

    @property
    def horizontal_axis(self) -> int:
        """Gets the horizontal axis perpendicular to the fiber axis.

        Returns:
            int: The index of the horizontal axis (0=x or 1=y).
        """
        if self.axis == 0:
            return 1
        return 0

    @property
    def vertical_axis(self) -> int:
        """Gets the vertical axis perpendicular to the fiber axis.

        Returns:
            int: The index of the vertical axis (1=y or 2=z).
        """
        if self.axis == 2:
            return 1
        return 2

    def place_on_grid(
        self: Self,
        grid_slice_tuple: SliceTuple3D,
        config: SimulationConfig,
        key: jax.Array,
    ) -> Self:
        self = super().place_on_grid(
            grid_slice_tuple=grid_slice_tuple,
            config=config,
            key=key,
        )
        permittivity_config = {
            "material": self.material,
        }
        self = self.aset("permittivity_config", permittivity_config)
        return self

    def get_voxel_mask_for_shape(self) -> jax.Array:
        width = self.grid_shape[self.vertical_axis]
        height = self.grid_shape[self.horizontal_axis]
        center = (height / 2, width / 2)
        grid_radius_exact = self.radius / self._config.resolution
        grid = (
            jnp.stack(jnp.meshgrid(*map(jnp.arange, (width, height)), indexing="xy"), axis=-1)
            - jnp.asarray(center)
            + 0.5
        ) / jnp.asarray(grid_radius_exact)

        mask = (grid**2).sum(axis=-1) < 1
        mask = jnp.expand_dims(mask, axis=self.axis)
        return mask

    def get_material_mapping(
        self,
    ) -> jax.Array:
        return jnp.zeros(
            self.grid_shape,
            dtype=jnp.int32,
        )

horizontal_axis: int property

Gets the horizontal axis perpendicular to the fiber axis.

Returns:

Name	Type	Description
int	int	The index of the horizontal axis (0=x or 1=y).

vertical_axis: int property

Gets the vertical axis perpendicular to the fiber axis.

Returns:

Name	Type	Description
int	int	The index of the vertical axis (1=y or 2=z).

An object with the shape of a cylinder.