Hello and welcome to the weight-paint survival kit.
I will talk about solving some of the most common issues
with weighting characters or attachments.
The tutorial is made with blender 2.67.
and i use the Avastar-armature,
but if you prefer then you can use your own armature as well.My working object will be the simple dress which i
have created in the

mesh attachments tutorial.
But before we rig the dress, we first will
apply the shrinkwrap modifier, so that we have
a clean and easy-to-handle starting point.

You may want to advance to the
Avastar: Weighting tutorial

if you are comfortable with rigging.

 

Transcription

Hello and welcome to the weight-paint survival kit.
I will talk about solving some of the most common issues
with weighting characters or attachments.
The tutorial is made with blender 2.67.
and i use the Avastar-armature,
but if you prefer then you can use your own armature as well.

My working object will be the simple dress which i
have created in the mesh-attachments tutorial.
But before we rig the dress, we first will
apply the shrinkwrap modifier, so that we have
a clean and easy-to-handle starting point.

And let me also give a reasonable name to our mesh,
so that it can be quickly identified later.
One easy method to rename your mesh is to
use the Outliner: Just double click on the mesh,
and rename it as you like.

Ok, we now have to solve 2 problems.
first we have to attach the dress to a rig,
or in blender slang:
we have to parent the dress to an armature.

And then: we have to add the bone weights.
well, the bone weights define exactly how the mesh
reacts to the bone movements of the armature,
and Blender already provides a method to rig a model
with automated calculation of initial weights.

And with Avastar we have added another option to
copy the weights from the Avastar default-character
to our own mesh. And here is how it goes.

Ensure that you are in Object mode,
and Select the dress and the armature both together.
Then open the tool shelf.
there: you find the Avastar rigging tool in the custom mesh panel.

Please take a look at the tool tip of the first option, namely “With weight Copy”.

So, when looking at the Outliner
then you can see that all Avastar
meshes are children of the Avastar armature.
Hence your dress will receive weights from all of its children
provided they are also currently visible in the viewport.

However: Avastar is clever here.
The weight copy function actually does a very good job
and it will not copy weights
from the head, or from the hands
to the dress,
so you are pretty save when you keep the Avastar meshes visible,
But hold on.

When we configured the shrinkwrap modifier in the previous part of this tutorial,
we also used the Avastar skirt template as target.
Hence it may be a good idea to make the skirt visible
and receive the weights from the skirt template as well.
And again, in general you do not need to hide the lower body,
because Avastar can figure out from where it has
to copy the weights.

However, let us be picky, and only keep the upper body and
the skirt visible, since only these 2 meshes have been used for the shrinkwrap.
Does that make sense to you ?

So now ensure that the dress and the armature are both selected.
Ensure further that you have enabled the option “with weight Copy”.

Keep all other options untouched,
and finally Click on: Parent to Armature,
And that’s basically all you need to do.
Now our dress is rigged and weighted.

But please be aware that the weight-copy is not a precise tool.
Especially when your mesh deviates from the Avastar shapes,
Then your resulting mesh weights will most probably need some manual
adjusting. But for our mesh we actually can expect that
the copied weights will be reasonable.
ok, let me quickly adjust the visibility of the Avastar parts
so that the character gets an appealing look again.

Now let us take a few moments and examine how the rigging tool
has changed our mesh.

First: You may have already seen it in the Outliner,
the Dress has been attached as a new child
to the Avastar armature.

So when you now move the armature to a different place in the 3D View,
then your dress moves along with it.

then, let us select the mesh and take a look at it’s
modifier stack.

there: you find an armature modifier.
All posing and animation of your mesh is
organized by means of this modifier.

By the way:
There should be
exactly one armature modifier
in the modifier stack of your rigged mesh.

But if you find 2 or more armature modifiers on the modifier stack of your mesh
then you should be alarmed.
In most cases you can fix this by deleting one of them.
But, well, You have to select the right one,
otherwise there will be trouble ahead.

Finally let us take a look at the meshe’s object data properties.

Here you find a list of vertex groups.
These vertex groups are the storage place for the bone weights,
and this is the most important piece of data within your mesh,
Actually these vertex groups define how the armature modifier will influence your mesh
during posing and animation.

So, you really must
get familiar with these vertex groups in order to survive.
But don’t worry, once you clearly understand how vertex groups affect your
animation, then everything will become very easy again.

But before we get deeper into the details here,
let us first try out how the dress can be posed and animated.

Select the armature,
go to pose mode,
and now select the green bones one by one with a right click,
rotate them by pressing “r”,
or move them around by pressing “g” ,
and see how your dress moves along with the armature.

Well, a closer look shows that the mesh is weighted,
but it does not work as nice as we might have expected.
So we have to check our weights and possibly modify them.

please ensure that your viewport-shading is set to: solid.
Otherwise you will not see the weights on your mesh.

Keep the armature in pose mode.
Now select the dress,
and go to weight paint mode.
Now the dress color changes to blue,
and this indicates
that none of the green control bones is weighted.

So what is going on here ?
well, the weights are actually only defined for the deforming Bones,
but these bones are currently hidden.

So here is the trick how to change that.

open the Tool shelf,
find the Custom mesh panel,
and locate the Show bones tool.

Here you find two preset buttons.
one for weighting,
and one for animation.

Apparently we will want to use the
weighting preset.

Now you see that the armature changes
a bit and instead of showing the green animation control bones,
it now shows the blue deforming bones.

You also might want to change the look of the bones
from octaheadron shape to stick shape.
You find the switch in the bone settings.

When you now right click on the SL bones
then you finally can examine the weights.

You also can rotate the bones by pressing “r”
on the keybord and move the mouse.
But be aware that
the blue bones can only be rotated, but not moved
around. Also Note that you always can reset your armature
into the T-Pose by using alt-r, for cancelling the rotations
of the selected bones.

And please remember one important point. When you are done with
your weight painting, then you should always switch back to the
Animation preset. And you should be aware that whichever pose you
created on the SL bones, as soon as you switch to the animation preset,
all bones snap back to where the green control bones are.

So by now we have introduced the basics of rigging,
and how we can control the weights. So, are you now ready
to improve your weighting skills as well?

Then just advance to the next part of this tutorial,
and get ready for an in depth excourse into all
about vertex groups and weight maps.