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

2 files changed, 111 insertions, 0 deletions

diff --git a/doc/python_api/examples/bmesh.ops.1.py b/doc/python_api/examples/bmesh.ops.1.py
new file mode 100644
index 00000000000..2eefb63a23d
--- /dev/null
+++ b/doc/python_api/examples/bmesh.ops.1.py
@@ -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
diff --git a/doc/python_api/rst_from_bmesh_opdefines.py b/doc/python_api/rst_from_bmesh_opdefines.py
index 3077798cbef..c1b6643389d 100644
--- a/doc/python_api/rst_from_bmesh_opdefines.py
+++ b/doc/python_api/rst_from_bmesh_opdefines.py
@@ -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
 """