Asset Creation: Maya Scenography Texturing - Creating Games with Unity and Maya - page 75

In this case, we will be spending some time within this portico, and so we
want to have a reasonable resolution so that the walls that surround the
player holdup to visual scrutiny. Now, we may discover that we don't need
2048×2048 (that is in fact a big texture). I suspect a 1024×1024 might do the
job just fine. But because Unity allows for some really easy adjustments in the
size that it imports files to, there is little penalty from creating the texture a
little larger for now, and then optimizing if need be or the situation allows. It's
better to have the resolution and not need it than the other way around.
Step 3: Open the UV map in Photoshop ( Figure 4.11 ).
Figure 4.11 UV Snapshot.
Preparing the UV Snapshot for Painting in Photoshop
Step 4: Copy the UV guidelines to another layer. The easiest way to do this is to
open the Channels palette (Window>Channels). Ctrl-click the Alpha 1 channel
(this will select the white lines), choose Edit>Copy, and then Edit>Paste. Open
the Layers palette and rename this new layer UV Guidelines .
Why?
The UV Snapshot in Photoshop is the image that will serve as the guide
to know what texture is being applied where. If a red line is painted
through the middle of a wall on this map, bring this map into the color
channel of the material, and the red line will appear in the scene (on the
wall). This is tremendously powerful since texture is placed right where it
should be on the mesh.
However, painting on top of the default image is a problem because it
covers up the guides that help to know where on the surface is being
manipulated. By duplicating the UV lines onto another layer, new layers
can be created between this new UV Guidelines layer and the Background
layer. So as the texture map is created it remains clear where on the
object you are applying texture.