'Composite Skin' is the technical name for an item of clothing that is Skin tight but does not Override the Skin Texture. This allows IMVU users to change Skintight items while keeping their underlying Skin Texture. Even better, it allows IMVU Creators to construct clothing items simply by painting them on as opposed to having to Mesh, map, Weight and Export their own entirely new Geometries.
Composite Skin Products deliver a pretty broad canvas to those Creators who are better painters than builders.
For the purposes of this tutorial, we assume you have read the following tutorials:
Avatar Body Parts Introduction Tutorial
Weighting in Skin Tutorial
Export the Mesh - .xmf Tutorial
Export Matirlas - .xrf Tutorial
Build Mesh - Select the Mesh
You will find the Weighting files in the IMVU Unified Installer.
With one of these files open, select the Body Part you wish to Export, then select the Edit Poly modifier that already exists in the stack.
Remember: you can build one Mesh that covers the entire Avatar body. This will require new Weighting but it can be done.
Build Mesh - Select All Polygons in That Mesh
In face select mode, select all of the Faces of the mesh.
Build Mesh - Change Material ID
Change all of the Material IDs on the mesh to material ID 1 - which is the UpperBody  material slot.
Build Mesh - Weight & Export
Weight the Mesh using Skin. To learn how to do this, please consult the Weighting in Skin Tutorial.
With the mesh selected (it should turn White in wireframe mode), choose Export in the file menu, scroll to the .xmf file format, name your Mesh file, click save, choose the Avatar Skeleton file that comes in the IMVU Unified Installer and then click next/finish until there are no Cal3D windows visible.
TIP: to avoid confusion with other Developers' products and therefore to avoid copyright infringement issues, please give your .xmf file a name that is easily recognizable as yours.
Build Mesh - Make Two Textures
In an Image Editor like Photoshop, using an Avatar Skin Texture as a guide, create a diffuse (opaque/color) Texture and an opacity/alpha Texture that match the size of the Avatar's Skin Texture. This Texture can be either 128X256 or 256X512.
To learn more about where to download Avatar Skin Textures, please consult the Textures Introduction Tutorial.
To learn more about Opacity Maps, please consult the Opacity Maps Tutorial.
Create Material - Launch Material Editor
In 3dsMAX, open the Material Editor and use the Eyedropper to select the Avatar's Multi-sub Material and then open the ID 1/UpperBody  sub-material - this is the upperbody submaterial.
Create Material - Add Diffuse Map
Click on 'Diffuse' and browse for your newly created Diffuse Texture. Then hit the back button on the Material Editor to get back to the ID 1/UpperBody  main area.
Create Material - Add Opacity Map
Click on the button that says 'None' next to the word 'Opacity' for this sub-material. In the dialog that appears, double click on the top option, 'Bitmap', and browse for your newly created Opacity map. Now close the Material Editor.
To learn more, go to the Opacity Map Tutorial.
Create Material - Export .xrf
Select nothing in the main 3dsMAX window, choose Export, scroll to the .xrf file format, name your Material file, choose the Material named 'UpperBody ' and click next/finish until there are no Cal3D windows visible.
Editor - Derive
Open Create Mode and Derive from one of the following products:
Editor - Override Body Parts
In the Config tab, choose which Body Part you want your Mesh to replace.
To learn more about Body Part replacement, please consult the Avatar Body Parts Introduction Tutorial.
Remember: If you want to use multiple Body Parts (ie - if you want to Override both the Topand the Pelvis), you must add .xmf files for each Body Part you want to Override. There are two ways to add multiple Body Parts to a product: The first is to just click on the ID number in the Config tab. The second is to click the 'Add' button at the top of the Meshes tab and choose which ID you wish the new Mesh to replace.
Editor - 1. Add Mesh .xmf
In theMeshes tab, browse for your newly Exported .xmf file. and hit the Apply Changes button.
Your new Mesh should appear with the existing Material applied to it. If this is the case, move on to the next step.
If this is not the case, you will need to check:
1. the Weighting in MAX (is the Physique Modifier turned on? Are the Vertices Weighted?)
2. the Skeleton .xsf file (did you use the Female04_Anime01_SkeletonMASTER.xsf file supplied in the Unified Installer?)
3. the exported Asset's file type (it should be .xmf - not .cmf or anything else)
Editor - 2. Add Texture
Add your Texture.
Editor - 3. Add Opacity map
Click the 'Add' button and browse for your new Texture.
Editor - 4 - Check 'Skin Composite'
To get your Composite Skin to show up on top of the Avatar Skin, make sure to check the 'Skin Composite' check box found in the Material Parameters panel.
Editor - Save & Submit
Save this product and Upload it. You have created a Skin tight Composite Mesh that can be derived by thousands of Creators from around the world.