How do I define complex geometries using trimesh?

Date	Category
2023-12-06 22:59:52	Structures

To define complex geometries using the Trimesh library, you must install Tidy3D as pip install "tidy3d[trimesh]", which will install optional dependencies needed for processing surface meshes. The Trimesh library provides some built-in geometries such as ring (annulus), box, capsule, cone, cylinder, and so on. Let’s create a ring as an example.

n_sections = 100 # How many sections to discretize the mesh.

# Create a ring mesh.
ring_mesh = trimesh.creation.annulus(r_min=9, r_max=10, height=1, sections=n_sections)

# Plot the mesh.
ring_mesh.show()

To use this geometry in a Tidy3D simulation, you need to convert the mesh into a tidy3d.TriangleMesh geometry. Use the from_trimesh() method to conviently convert the mesh to a Tidy3D geometry. From there, you can further define the Tidy3D structure and put it into a simulation.

# Define a tidy3d geometry from a mesh.
ring_geo = td.TriangleMesh.from_trimesh(ring_mesh)

This example shows how to create many different complex geometries using Trimesh.