include an example in the api docs for using bmesh operators to make 2 links in a chain.

This commit is contained in:
Campbell Barton 2012-11-28 15:08:45 +00:00
parent 96136d3d88
commit f828a318f5
2 changed files with 111 additions and 0 deletions

@ -0,0 +1,106 @@
# This script uses bmesh operators to make 2 links of a chain.
import bpy
import bmesh
import math
import mathutils
# Make a new BMesh
bm = bmesh.new()
# Add a circle XXX, should return all geometry created, not just verts.
bmesh.ops.create_circle(
bm,
cap_ends=False,
diameter=0.2,
segments=8)
# Spin and deal with geometry on side 'a'
edges_start_a = bm.edges[:]
geom_start_a = bm.verts[:] + edges_start_a
ret = bmesh.ops.spin(
bm,
geom=geom_start_a,
angle=math.radians(180.0),
steps=8,
axis=(1.0, 0.0, 0.0),
cent=(0.0, 1.0, 0.0))
edges_end_a = [ele for ele in ret["geom_last"]
if isinstance(ele, bmesh.types.BMEdge)]
del ret
# Extrude and create geometry on side 'b'
ret = bmesh.ops.extrude_edge_only(
bm,
edges=edges_start_a)
geom_extrude_mid = ret["geom"]
del ret
# Collect the edges to spin XXX, 'extrude_edge_only' could return this.
verts_extrude_b = [ele for ele in geom_extrude_mid
if isinstance(ele, bmesh.types.BMVert)]
edges_extrude_b = [ele for ele in geom_extrude_mid
if isinstance(ele, bmesh.types.BMEdge) and ele.is_boundary]
bmesh.ops.translate(
bm,
verts=verts_extrude_b,
vec=(0.0, 0.0, 1.0))
# Create the circle on side 'b'
ret = bmesh.ops.spin(
bm,
geom=verts_extrude_b + edges_extrude_b,
angle=-math.radians(180.0),
steps=8,
axis=(1.0, 0.0, 0.0),
cent=(0.0, 1.0, 1.0))
edges_end_b = [ele for ele in ret["geom_last"]
if isinstance(ele, bmesh.types.BMEdge)]
del ret
# Bridge the resulting edge loops of both spins 'a & b'
bmesh.ops.bridge_loops(
bm,
edges=edges_end_a + edges_end_b)
# Now we have made a links of the chain, make a copy and rotate it
# (so this looks something like a chain)
ret = bmesh.ops.duplicate(
bm,
geom=bm.verts[:] + bm.edges[:] + bm.faces[:])
geom_dupe = ret["geom"]
verts_dupe = [ele for ele in geom_dupe if isinstance(ele, bmesh.types.BMVert)]
del ret
# position the new link
bmesh.ops.translate(
bm,
verts=verts_dupe,
vec=(0.0, 0.0, 2.0))
bmesh.ops.rotate(
bm,
verts=verts_dupe,
cent=(0.0, 1.0, 0.0),
matrix=mathutils.Matrix.Rotation(math.radians(90.0), 3, 'Z'))
# Done with creating the mesh, simply link it into the scene so we can see it
# Finish up, write the bmesh into a new mesh
me = bpy.data.meshes.new("Mesh")
bm.to_mesh(me)
# Add the mesh to the scene
scene = bpy.context.scene
obj = bpy.data.objects.new("Object", me)
scene.objects.link(obj)
# Select and make active
scene.objects.active = obj
obj.select = True

@ -53,6 +53,11 @@ to perform useful operations.
This API us new in 2.65 and not yet well tested.
Operator Example
++++++++++++++++
This script shows how operators can be used to model a link of a chain.
.. literalinclude:: ../examples/bmesh.ops.1.py
"""