The goal here is to transfer attributes from one or more
Source meshes to a Target mesh.
For this example, our source meshes are: an
enveloped cyborg character (with UVs created and textures applied), a
shape-animated female head, and a grid with a face texture applied to
it. Our target mesh is a human male figure, fresh
from the modeler’s oven.

Since GATOR works best when the source and target meshes are lined up
as closely as possible, that should always be your first step. Start by
aligning the cyborg mesh with the human male mesh.

With the target mesh (the human male figure)
selected, choose Get > Property > GATOR from
the toolbar (on the left-hand side of the interface). You’ve just
launched a picking session and you need to pick the source
mesh (the cyborg).

Once you pick the source mesh, the GATOR
property editor lets you choose attributes to transfer and
control how they are transferred. What we’re interested in here are the
options under the Transfer Properties heading. Click
the two Transfer buttons under that heading to
transfer the UVs, Materials and Envelope
Weights from the source (cyborg)
mesh to the target (human male)
mesh.

Once the attributes are transferred, check to see how well the property
transfer worked. If your meshes are animated, you should see how they
look in different frames. You can also hide or
delete the source mesh at this stage.

When you’re working with a library of assets, you can use GATOR
multiple times to transfer attributes from multiple sources to your
target. After lining up the textured grid with the
target mesh, we can select the face’s
polygons and apply another GATOR property, this time
picking the grid as the source.
Though it’s not necessary, you can also make these polygons into a
cluster, or detach them entirely from the mesh.

In the GATOR property editor, click the
Edit Transfer button to open a new property
editor that lists all of the transferable properties in a
drop-down menu. Now you can transfer specific attributes.

Choose UV Space from the drop-down, click
In Prop in the upper grid control, and then click
the TransferMerge button to transfer the grid’s UVs.
This adds a second set of UVs to your
target mesh.

Now that you have a UV set to accommodate the face texture, you need to apply the texture to the target model.

Select the face polygons and choose Get
> Texture > Image from the Render
toolbar. In the texture property editor, pick the
face texture from the list of images used in the
scene, and pick the newly transferred UV set from
the Texture Projection drop-down list.

At this point, the grid has transferred the UVs to the target model’s
head, but the result doesn’t look quite right, does it? Since GATOR is
a live operator that lives in the construction history, you can adjust
the source mesh to reposition the
UVs, all without reapplying the effect.

To get a better look at the target mesh, change the
grid’s display properties so that only its wireframe
is displayed.

To display a single object in wireframe mode, click on the
pallette icon (in the bottom left-hand corner of the
interface). Click the W button (for wireframe) to
start a picking session. Pick the object(s) you want to see in
wireframe (the grid, in this case) and
right-click to end the pick session. Then go to the
viewport‘s display menu and choose Override
Object Properties to see the object(s) in wireframe.

Now you can bend the grid around the head to position the transferred
UVs. Small manual tweaks to the face grid will help you line them up.
Use the texture editor to fine-tune the texture’s placement.

GATOR can transfer shape animation from one mesh to another even if
their respective topologies are different. To transfer shape animation,
apply a GATOR property normally. When the property
editor opens, click the Transfer button
under the Shape Animation, Envelope Weights heading.
If the source mesh has envelope data that you don’t want to transfer,
the easiest thing is to delete the envelope operator
instead of clicking Edit Transfer.

Transfer shape animation from the female head mesh onto the human male
mesh. Once you transfer the animation, you can open the Shape
Manager and see all the animated shape information.

Chinny
XSI Product Manager
Softimage|XSI

Chinny – who’s never known as Jason Brynford-Jones – brings over 10
years of 3D experience to his role as XSI product manager. A Welshman
raised in London and now based in Montreal, Chinny originally started
at Softimage as a demonstrator, where he traveled the world showcasing
Softimage technology. When not tending to his newborn daughter, or
writing plug-ins to tend to the XSI community, Chinny can be found
writing comedy sketches for his own twisted amusement.

The Generalized Attribute Transfer Operator (GATOR) in SOFTIMAGE|XSI
lets you transfer attributes like UVs, Materials, Vertex Colors,
Envelope (Skin) Weights and even Shape Animation to and from completely
different characters.

GATOR uses the closest surface or closest points in its calculations,
and so works best if the source and target meshes are lined up as
closely as possible. This is especially true for shape animated
objects. When transferring lip synch shape animation, it’s best to find
a frame where the mouth is open. When transferring Envelope Weights and
UVs, find a frame where they are lined up (usually the T-pose).

Although multiple GATOR properties can be applied to one mesh, the more
GATORs you have, and the more detailed the source and target meshes,
the slower things become. However, simply freezing the modeling
operator stack will speed things up again.

If you have the same model, one with good UVs and one with good weighting, you can simply transfer one to the other.

Of course, there are many more options in GATOR not covered here, as
they apply only to some quite specific scenarios. This example uses the
default settings.

SOFTIMAGE
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ph. 514.845.1636