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Home: Autodesk Maya Online Help
Extrude polygons in an arc or wedge shape
Polygon creation
Duplicate polygon faces
Create symmetrical polygon
meshes
Maya lets you create
polygon models that have symmetry. Symmetry is when a form
has balanced proportions across a dividing line or axis. There are many
types of symmetry possible. The most common types of symmetry are bilateral
symmetry and radial symmetry.
In Maya you can model
a polygon mesh symmetrically using the following features:
Using Duplicate
Special to create a symmetrical mesh
The Duplicate
Special feature lets you copy any object across the X,
Y, or Z axis using the object’s pivot point as a reference point.
Duplicating an object in this way creates an identical copy that
is separate from the original.
To mirror a polygon mesh across its pivot point
using the Duplicate Special feature
- Select the polygon mesh and choose
Edit > Duplicate Special > .
- Set the Translate and Rotate values
to 0.
- Set the scaling to -1 for the axis (X,
Y, or Z) across which you want to mirror the polygon mesh.
- Click Duplicate Special.
NoteWhen you scale an
object by -1 across its axis of symmetry, the surface normal will
be flipped. Keep this in mind when you need to perform other modeling
operations on the mesh. You can reverse the normals using
Normals > Reverse.
Using Mirror
Geometry to create a symmetrical mesh
Use the Mirror
Geometry feature when you have created one half of a
model and want to create an identical duplicate mirrored half. The
original half of the polygon mesh is duplicated across an axis of
symmetry based on its bounding box or pivot point. You can also
merge the duplicated polygon mesh with the original mesh to create
one resulting polygon mesh.
To
mirror a polygon mesh across its bounding box using the Mirror
Geometry feature
- Select the polygons and choose
Mesh > Mirror Geometry > .
- Choose the direction to mirror the polygons
and whether to merge the duplicated polygons into the original mesh.
- Click Mirror.
Using Mirror
Cut to create a symmetrical mesh
You can model a polygon mesh and then copy
it across a user defined axis of symmetry using the Mirror
Cut feature. The Mirror Cut feature
lets you manually position the axis that the mesh will be duplicated
across. You can also merge the duplicated polygon mesh with the
original mesh to create one resulting polygon mesh. Mirror
Cut can provide for interesting symmetry results depending
on where you locate the axis of symmetry.
To model a polygon mesh symmetrically
with Mirror Cut
- Select a polygon mesh.
- Select
Mesh > Mirror Cut.
- Use the manipulator to adjust the plane
of symmetry.
Note
- If you position the plane of symmetry
so it is beyond the positive edge of the original object, then both
the original object and its mirror image will disappear (except
for one face on each). If you want to mirror the object in the direction
of its positive edge, then move the symmetry plane so it intersects
the original object and rotate the symmetry plane 180 degrees.
- When you delete history of an object
on which you have applied
Mesh > Mirror Cut,
the plane of symmetry is not deleted. You must manually delete the
plane of symmetry.
Using Subdiv
Proxy to create a symmetrical mesh
Subdiv proxy lets you
simultaneously preview the smoothed version of the polygon mesh
while you modify the original mesh. The original mesh appears partially
transparent so you can view the smoothed version beneath. When you
turn on Subdiv Proxy’s Mirror
Behavior option, you can modify the original half of
the polygon mesh while the other half updates.
To
model a polygon mesh symmetrically using Subdiv Proxy
- Select a polygon mesh.
- Select
Proxy > Subdiv Proxy > .
- In the Subdiv Proxy options window, set Mirror
Behavior to Full, set
the Mirror Direction, and click Smooth.
The original mesh is
mirrored along the Mirror Direction.
- Modify one half of the subdiv proxy (for
example, using
Edit Mesh > Extrude).
The modification automatically
updates on the opposite half of the subdiv proxy.
- If you want to combine the two halves,
select
Proxy > Remove Subdiv Proxy Mirror.
Notes on mirroring polygon
meshes using Subdiv Proxy
- Mirroring only works across the world
axes. Mirroring an object that has been arbitrarily rotated may
produce unexpected results; some geometry may overlap as a result.
- If you modify the mirrored half
of the subdiv proxy in object space mode, dragging a
manipulator in one direction will modify the proxy in the opposite direction.
- If you modify the mirrored half
of the subdiv proxy in world space mode, dragging a manipulator
in one direction will modify the proxy in the same direction.
- If you modify the original half
of the subdiv proxy, in object space or world space mode, dragging
a manipulator in one direction will modify the proxy in the same direction.