Updated in December-2013: This video shows how you can use the Avastar Shape sliders to affect your custom mesh. Please be aware that this feature simulates the SL/OpenSim Shape Editor. However Avastar simulates the slider influence for classic bone weighting (as SL provided until november 2013) as well as Fitted Mesh Weighting (which is now officially supported by SL as well).

Transcript

Hello and welcome.
This is a quick tip for enabling custom shape-sliders in Avastar.
This video is made with a development version of Blender 2.7,
and with a pre-release of the Avastar 1.1 Addon for Blender

Here, you see a default-Avastar character with some
textures applied.
And this is our working model, a simple dress.

In the first step we will rig the dress.
So, lets start and select the Armature,
and then shift select the dress.
Actually the order in which you do that is not important.

Now proceed by Opening the tool shelf,
navigate to the Custom Mesh section,
and locate the rigging panel.

We also want to get some initial weights for our dress,
For this purpose we select: Weights from meshes.

This option will copy the weights from the default Avastar
to our custom mesh.

However if your custom mesh already contains weights?
then you can use the option “keep as is”.

So when this option is selected?
then Avastar just rigs your mesh and uses the existing weights.

But for now we want to copy weights from meshes.
Finally ensure that the Mesh and the Avastar Armature are both selected,
then click on: parent to Armature.

Your mesh is now rigged and weighted.
You can check that by going to pose mode and pose the model,
and you see that the dress will follow the Pose.

We have added a new view option, which lets you see immediately
which bones are weighted.
Select the mesh,

Then in the Tool Shelf?
Navigate down to the option: “Show Bones”,

and click on the preset button: “Weight”.

Now all weighted skeleton bones show up immediately.

I also prefer to change their view-type to sticks.
then i can better see the weights.

And if you are curious,
then you also can open the
advanced bone display,

and here you see that the Deform set is selected.
This set always contains the bones which can be weighted.
Currently this set is identical to the well known Second Life Base Bones.

And here is one more tip:
Please be aware that the weight display only works
correctly in Solid-View mode.

ok, lets switch back to object mode,
and select the armature again,
and open the armature Object Properties.

If it is not yet visible,
then load the Shape user interface.

Then locate the Torso-sliders and change the Torso-length.

You see that the Avastar meshes are influenced by the slider value changes,
while your custom mesh keeps its shape as it is.

Ok, let us see how we can change that.

first Lets put the Torso Length slider back to its original value.
You can do this by clicking on the icon
that appears on the right side of the slider.

by the way, this icon indicates that the slider
is a skeleton slider,
which changes bone length.
And whenever this icon appears,
it also indicates that the default value for this slider has changed.

ok, the armature is reset.
proceed by selecting the mesh,
and lookup the rigging-panel in the tool shelf.

Now click on the Slider’s “Attach” button.

Technically this will create 2 Shape-keys for the mesh.
But actually you can forget about these shape-keys,
because Avastar knows how to use them for your benefit.

Well, so let us switch back to the Object-properties section
of the Avastar armature.
And change the torso length again.

Indeed, now the mesh stretches and shrinks with the slider-changes.

But hold on, when you try to use other sliders like the belly size for example,
then the dress does no longer react. this is because some sliders are
only changing the avatar mesh, but not its bones.

And this is exactly the same behavior as we can see in Second Life.
So, if you change a shape-slider that does not change the bone length,
this will not influence the custom mesh.

We did this on purpose,
because now you can simulate in blender how the Second-Life shape-sliders
will later affect your meshes.

by the way,
you see that the morph sliders have got a different Icon for resetting.
This makes it easy to see which sliders change bone length,
and which sliders only morph the Avatar mesh.

Ok, but this is not convenient.
It would be nice if the custom mesh could be morphed with all sliders.
But we do not have this feature in Second Life.

However, recently Linden Lab has announced the support for fitted mesh.
This is a method to propagate the influence of some more shape sliders to meshes.

Avastar supports this new method as well.
And here is a basic workflow for how to use Avastar’s new built-in tools
for your own fitted mesh projects.

First lets cleanup, This is important!
Set your Avastar back to the default Shape.

Select the dress,
open the tool shelf and locate the rigging panel.

Then detach the shape sliders from your mesh.
You must do this because we are going to do a radical change in the
bone setup. Thus we have to do a full reset
of the custom shape slider system.

Now, take another look at the rigging panel.
Here you also find 2 preset buttons
for “Classic” rigging
and “Fitted Mesh” rigging.

By default we get the Classic preset. This is
what we used during the last couple of minutes.

But now we Select the Fitted mesh preset instead.

As you can see the visible skeleton changes dramatically.
This is so, because now other bones take control over the
avatar, the Collision Volume bones.

And these bones have been prepared with some reasonable
weight presets for the custom mesh.

Lets go to weight paint mode and inspect the weights.

And now let us check how this works with our slider system.

Put the mesh back to Object mode,
then lookup the rigging panel in the tool shelf.

Now attach the sliders again to the mesh,
and your basic setup is done.

Lets test if that works as expected.
Select the armature,
and open the object properties section.

Now try out some of the volume sliders,
like belly-size for example.

Well, you realise soon that this is not a perfect fitting.
If you want to get better results,
then you currently have to optimize the weights carefully
by hand.
And you have to use alpha masks to hide any poke through of
your Avatar mesh.

Please note that using alpha masks for this purpose
is a standard method to handle poke through.
There is absolutely nothing wrong with this approach.

So, we are now at the end of this tutorial.

Please note that Avastar’s default settings are
meant as reasonable initial configurations.

And be prepared that you always have to optimize your weighting.
And honestly, the default weights of the SL Avatar
do not work well on custom meshes in general.

So please be prepared for that, and do not
expect the one-button-click-and-be-happy solution.

From here on?
you have to take your time to explore the Avastar tool,
and hopefully you will have some fun with it.

Thanks for watching.