How to draw a circle hole by bmesh on the plane?

Question

How to draw a circle hole or a square hole by bmesh on the plane object? I tried with below but failed it only draws circle rather than a hole.

bm=bmesh.new()
ret=bmesh.ops.create_circle(
    bm,
    cap_ends=False,
    radius=1.8,
    segments=8)
#print('circleret:',ret)
bmesh.ops.translate(
    bm,
    verts=ret['verts'],
    vec=(5.0, 24.0, 0.0))
mycircleface = bm.faces.new(ret['verts'])
me1 = bpy.data.meshes.new("Circle")
bm.to_mesh(me1)

Answer 1

Round or square hole in round or square mesh.

Would be many ways to skin this cat.

• Add a plane remove its one face. Size square_size
• Subdivide the plane equally using cuts
• Add a circle with 4 * (cuts + 1) segments, radius circle_radius
• Bridge the loops from square to circle

Test script.

import bpy
import bmesh
cuts = 3
square_size = 1
circle_radius = 2
context = bpy.context
collection = context.collection
me = bpy.data.meshes.new("Hole")
bm = bmesh.new()
bmesh.ops.create_grid(
        bm,
        x_segments=2,
        y_segments=2,
        size=square_size,
        )
bm.faces.remove(bm.faces[:].pop())
bmesh.ops.subdivide_edges(
        bm,
        edges=bm.edges,
        cuts=cuts,
        )
bmesh.ops.create_circle(
        bm,
        segments=4 * (cuts + 1),
        radius=circle_radius,
        )
bmesh.ops.bridge_loops(
        bm,
        edges=bm.edges,
        )
bm.to_mesh(me)
ob = bpy.data.objects.new("Hole", me)
collection.objects.link(ob)

This makes one of each as mesh and hole. Circle in circle (Square in square) can be done as above, simply making one twice.

Could wire this up similarly to

Create Circle with Inner Radius

giving option of square / circle inner outer and ngon fill.

See also

How can I morph a flat plane to be a flat cirlce? re morphing one to another.