A Sims 2 mesh is comprised of 4 parts:
Name.........................Abbreviation.......File extension
Geometric Data Container.........GMDC................5gd
Geometric Node...................GMND................5gn
Shape............................SHPE................5sh
Resource Node....................CRES................5crFigure 1.
The GMDC corresponds roughly to the XSKIN in the original Sims.
The SHPE & CRES corresponds roughly to the CMX in the original Sims,
but the package file with the skin texture also has elements that
over-lap the similarity.
This tutorial assumes you have SimPE and it is working; it also assumes
you have made a temporary skin clone of similar shape and design as the
mesh needing skinned.
Once you have a mesh that needs a skin (be it hair, body, or an accessory)
extract the CRES and SHPE with SimPE.
Figure 2.
Now open the temporary skin you made earlier in Body Shop and find a
blank area (white) and right click, a menu will pop up and you should
select "Add" -- Add the CRES and SHPE to your skin package.
Figure 3.
Once the CRES and SHPE have been imported select the 3D ID Referencing File.
Figure 4.
In the Plug-in View at the bottom of SimPE, left click then right click
and delete the existing Resource Node reference.
Figure 5.
In the Plug-in View at the bottom of SimPE, left click then right click
and delete the existing Shape reference.
Figure 6.
To the left of the Plug-in View, click "Package".
Figure 7.
The SimPE PackageSelectorForm pop-up should appear; left click to select the
Recource Node and the Shape, then drag and drop each into the 3D ID
Referencing File. You may only select and move one at a time.
Figure 8.
In the Plug-in View, left click to select the Resource Node, then click
the "up" button until the Resource Node is at the top of the list.
Figure 9.
In the Plug-in View, left click to select the Shape, then click the "up"
button until the Shape is below the Resource Node.
Figure 10.
When the Resource Node and Shape are in the correct position in the list,
click the "Commit" button.
Figure 11.
In the upper portion of SimPE, select then right click & delete the
Resource Node and the Shape from the list.
Figure 12.
Save the file. If you have not already done so, move both the MESH and
the SKIN packages to the Downloads folder. Start Body Shop and make the
first real recolour.
Hope this helps to de-mystify the process.
