Facial Skin Layered Mapping

 

Part 2.1  – Flattening: Preparation and the Flatten command

 

 

Before You Begin

You should save to a new version backing up the work you did in part 1 and update the revision notes in the Model Control EXCEL file.  When saving to a new version it is strongly recommend that you take the following steps to insure against latent model corruption:

a)     Save the project file which should have the model embedded in it.

b)     Save the model to a new version.  When the file dialog box opens increment the version number in the file name (the model version number should be the same as the project version number thus indicating that it came from this version of the project file).  Click on ‘Save’.

c)      Do Project->New.  DO NOT SAVE.

d)     Open the version of the model you just saved.

e)     Embed the model into the project file.

f)        Save the project file.  When the file dialog box opens just select the last project file you saved thus putting that name into the filename entry field, then modify the filename by incrementing the version number.  Click on ‘Save’.

 

Note: These instructions are for a Windows PC.

 

Introduction

Flattening is the hardest most tedious part of mapping.  You flatten the mesh so the maps will lay flat and not deform or stretch.  The problem is map stretching that occurs when the patches change shape during flattening.  A:M has two tools to help with this: the ‘Flatten’ command and UV Mapping.  I do not recommend UV mapping as it is currently implemented in AM: it tends to stretch the patches near the edges; it’s very hard to adjust the mesh (and it always needs adjusting); if you have to redo the maps or the decal (and you almost always do) it is very time consuming and many times its easier to just start from scratch; it only works for front facing mesh.   Physically flattening the mesh is simply quicker, easier and more flexible.  The ‘Flatten’ command does a very good job but can not be used effectively for meshes that wrap around as our neck area does. 

 

It is possible to get rid of almost all stretching however; I’ve found that you reach a point of diminishing returns.  That is, the last little bit takes so long to do and there is really very little gain.

 

We’ll use the flatten command which does a really good job of eliminating stretching on the most important face areas.  Then, for the neck which wraps around, we’ll do some manual flattening.  Then we will use a method that will show us any stretching that will occur and attempt to bring these areas to a acceptable level.

 

  1. The mesh must be split somewhere in order to flatten it and the best place is back of the neck.  In looking at this I see the center section is a bit to wide.  I also notice that two of the hooks will cross the hair line and this can cause problems – Figure 2.1.

 

 

 

Figure 2.1

 

  1. To prepare the back of the neck for splitting and get rid of the hooks that might cause problems I simply extend the hooks down – Figure 2.2.  After doing this I add the new CPs to all the groups that need them including Head, Head Skin and SkinMapArea.

 

 

Figure 2.2

 

  1. Now I create the groups to flatten and apply decals to: FrontSection – Figure 2.3 and BackSection – Figure 2.4.

 

 

Figure 2.3

 

 

Figure 2.4

 

  1. To begin flattening the FrontSection, select it and hide everything else.  The face and front neck areas will respond to A:M’s flatten command well so these are selected, the unnamed group is named tempFrontSectionOne and then the rest of FrontSection is locked – Figure 2.5.

 

 

Figure 2.5

 

  1. Open new action and name it FrontSectionFlatten and go to muscle mode and select all the unlocked mesh.
  2. Press ‘n’ to expose the pivot point, go to the side view and grab the green pivot translate point and rotate it so that it points towards the back of the head.  Now grab the center of the pivot point and move it left until it is just behind the unlocked section of the mesh.
  3. Go to a side view, right click and select flatten.  You should wind up with something that looks like the mesh shown in the right window of figure below in figure 2.7.  With the unlocked mesh still selected hit ‘h’ to temporarily hide all but the newly flattened mesh.
  4. Patches will sometimes lose their shape or relative size when the flatten command is used.  If you have the modeling window still open in the background, doing <Alt>v will place the windows next to each other and you can compare the flattened patches with the un-flattened ones.  Think twice about making any adjustments here as sometime flatten does a very good job but if you see any obvious deformation, carefully correct it.   I need to make the patches in the neck area thinner -- Figure 2.6.

 

 

Figure 2.6

 

  1. After carefully adjusting any obvious patch distortions, save and then unhide and unlock all. 
  2. Now the rest of the FrontSection must be flattened.  Select the FrontSection and hide the rest then select the TmpFrontSectionOne group, invert the selection to select the as yet un-flattened portion of the mesh then lock the flattened section.  You should wind up with something like Figure 2.7.

 

 

Figure 2.7

 

  1.  We want to preserve the flattening we’ve just done and be able to fall back to this if we totally screw up the manual flattening we are about to do so, save to a new version at this point and update the revision notes.

 

Next -- Part 2.2  – Flattening: Manual Flatten Techniques