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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.