Facial Skin Layered
Mapping
Part 2.3 –
Flattening: Stretch testing and final adjustments
Before You Begin
Open
your project file is needed. Hide all
but the FrontSection group. Open the
flattening action and go to muscle mode.
Zoom to extents ([Shift]z).
Download the image below and save it in the models
reference folder (note: although we will use this for a decal to test for map
stretching, it will not be a permanent part of the model so we do not want to
save it in the Maps folder). To download
the image below, click on it and follow instructions. Rename the image to cube1.

Introduction
Now we’ll finish the flattening by testing for map
stretching, adjusting the mesh, testing again and so forth until we minimize
the stretching.
- Apply
the image you just saved to the FrontSection group you just
flattened. When the decal appears
in the action window ignore it for the moment and go to the PWS and expand
the new Decal sectrion and adjust the image properties as shown in Figure
2.3.1.

Figure 2.3.1
- Now
position the decal by right clicking on the decal icon and selecting Position
and adjust it in the action window until it just covers the flattened mesh
(Figure 2.3.2). You may need to
adjust the decals size – be sure to hold down the shift key if you do this
so that the decal maintains its aspect ratio.

Figure 2.3.2
3. Now switch to the modeling window and go into shaded
mode. Inspect the grid that is projected
on to your model from all views. The
squares should remain as close to square as possible. Looking at mine (Figure 2.3.3) I can see that
the face (flattened using the flattened command) looks good – from the front
view anyway – but the neck area leaves something to be desired.

Figure 2.3.3
- Looking
at the side view (Figure 2.3.4) I can see that the section near the ear is
a mess – even though most of this section will likely be covered by hair,
this much distortion in the grid is not good and definitely needs to be
fixed. The face area (the most
important area) remains acceptable.
The slight dip in the grid below the mouth is a result of a 5 point
patch and in most cases you can not fix this.

Figure 2.3.4
- If
you place the image in shaded wire frame you can see which patches are
distorting the mesh and need to be adjusted. Quite a bit of adjusting is sometimes
needed. Often you have a row of
patches were the grid is compressed – this means that this row of patches
is too wide. You’ll need to reduce
the width of the patches and likely this means moving all the patches on
one side over. Another method of
fixing the mesh is to set the modeling window and the action window side
by side and, going to wire frame mode, comparing the flattened patches to
the model and looking at the relative size and shape of a patch.
- Once
you made some adjustments you must delete the decal’s stamp and reapply it
to see the effect of your adjustments.
Remember, getting it perfect is not worth the time.
- Working
on my flattened mesh, I wind up with what is shown in Figures 2.3.5, 2.3.6
and 2.3.7.

Figure 2.3.5

Figure 2.3.6

Figure 2.3.7
- Notice
that the corner of the ear (Figure 2.3.7) is much better though not
perfect however it is good enough for this area behind the ear and where
it goes under the hair.
- Also,
in the back there will likely be a lot of distortion (Figure 2.3.8). This is due to the fact that in the
action the end CPs are being bent due to the spline that stretches from
end to end. There is a way around
this but for now we’ll leave it.

Figure 2.3.8
- Now
you should close the action window, unlock all, save to a new version,
save the flattening action to file in the Action folder then, re-embed the
action. To better organize all the
actions and keep everything straight, create a subfolder in the Actions
folder named Decals – all decal flattening poses will be stored here. Name the action
HeadSkinFrontSectionFlatten.act.
- Next
hide all but the BackSection group shown in Figure 2.3.9.

Figure 2.3.9
- Compared
to the FrontSection this will be a piece of cake to flatten. Create a new action and flatten this – using
the ‘Flatten’ command on this section may cause excessive decal
deformation and you may want to flatten this manually. In any event be sure to compare the
flattened version to the un-flattened
in the model window to check the general size and shape of the
patches. Then repeat the general
steps in step 9 above saving the new action to the Decals subfolder you
created and naming the new action HeadSkinBackSectionFlatten.act.
Go to Next: Part
2.4 – Final Touches Before Mapping