Rebake UV Layout
Rebake UV Layout
Second Life uses an automated Rewrap to improve the Character look after its shape has been modified. Unfortunately this automation does not apply to Custom Mesh characters as well.Avastar’s Rebake UV Layout is a similar function. However the result are not (yet) equal to SL’s bake tools.
Note: The Rebake UV Layout button is only available when the active mesh has a UV Layout.
The SL System Avatar uses one single mesh for female and male characters. And the Shape system uses mostly Morph keys (Shape keys) to modify the mesh into your custom shape. While this works very nice for the meshes, this approach often results in huge distortions of the UV Layout depending on the sliders settings and depending on the Gender Setting. Because of this SL introduces an automatic rebake of the UV Layout whenever you changed the Slider settings.
We have added a similar technique to Avastar. The UV Rebake tool produces very similar but slightly different results compared to the SL solution. For more details see the Video. Note: The video was made with Avastar 1 but it applies also to Avastar-2.
You find the Rebake UV Layout Tool in the Avastar Tools panel when you have selected a Mesh that contains a UV Map.
Finding troublesome Vertices
Doubles (Find Duplicates)
The Doubles Operator selects all vertices which are recognized as duplicates.
Note: this operator does not preserve the original vertex selection. So after the operator is called, only the duplicate vertices are selected or no vertex is selected when the mesh is clean (has no duplicates)
> Weight Limit (too many Weights on Verts)
The > Weight Limit Operator selects all vertices for which the number of assigned weights is > a given number (4 by default).
Note: this operator does not preserve the original vertex selection. So after the operator is called, only the vertices with more than the given number of weights are selected or no vertex is selected when the mesh is clean (all vertices have less than or exactly the given number of weights assigned).
Note: When you have selected multiple Objects you will find a report in the Blender Console with one line per object indicating the number of vertices with too many weights
Unweighted (Find Unweighted Vertices)
The Unweighted Operator selects all vertices which are not assigned to any Weight Group.
Note: this operator does not preserve the original vertex selection. So after the operator is called, only the unweighted vertices are selected or no vertex is selected when the mesh is clean (all vertices have weights)
Note: When you have selected multiple Objects you will find a report in the Blender Console with one line per object indicating the number of unweighted vertices.
Zero weights (weigthsum == 0)
The Zero weighted Operator selects all vertices for which the sum of all assigned weights is 0.0 (zero).
Note: this operator does not preserve the original vertex selection. So after the operator is called, only the zero weighted vertices are selected or no vertex is selected when the mesh is clean (all vertices have weightsums > 0)
Note: When you have selected multiple Objects you will find a report in the Blender Console with one line per object indicating the number of vertices with weight sums == 0
When you want your mesh to keep left/right symmetric then Blender offers a function which tries to enforce symmetry on a selection of vertices. However this can sometimes be a bit cumbersome because you need to find and select the vertex pairs before applying the operator.
The Asymmetry finder does this for you now as it automatically selects all vertices/edges or faces which are not symmetric on your mesh.
Snap to Mesh
This option is the small sister of the Shrinkwrap modifier. Here you first select a set of vertices in edit mode, then you call the Snap to Mesh function. This will snap your vertices to the closest vertex it can find on any other mesh.
In the operator redo panel you have a few more options:
- Snap range: the maximum distance from a vertex to a snap point if a vertex is not close to any snap point then it is marked as out of range.
- Snap Selected: You can use this tool only for finding the out of range vertices without actually snapping them
- Mark Out of Range verts: After snapping only the out of range verts are marked. This helps to quickly find those verts who could not be snapped.
Freeze a mesh
The Avastar Meshes can not be modified. As soon as you try to do this, you will get very bad distortions. This is due to how Shape keys are handled in Blender.
The freeze either creates static meshes from your rigged meshes, or modifiable versions of your selected meshes. The tool basically removes all shape keys and all Avastar control data.
The Freeze Tool is used in following situations:
- Ensure Blender is in Object Mode.
- Select all parts which you want to freeze.
- Set the freeze options.
- Freeze Selected.
Select all parts of the Avastar meshes which you want to use for your own character:
Note: The frozen Meshes do no longer react in the exact same way to the Avastar sliders as the original Avastar character does. However, the meshes behave exactly in the same way as they will behave when imported into SL, OpenSim or other compatible virtual environments.
What you should know
- When you select to Keep the Original, then the original mesh and your frozen mesh will overlap and you might not be able to see that there are actually 2 meshes now.
- When you select to Delete the Original, then the Original Avastar mesh is fully replaced by your frozen version.
- When you select to Hide the original, then the Original Avastar mesh will be hidden from view, then you only see the frozen version.
- when you enable Standalone Posed then your frozen mesh will be detached from the armature and it will end up as a simple non rigged static mesh.
- When you enable Remove Weight Groups then all weight groups of the frozen mesh will be deleted and you end up with a static non rigged mesh without any weights associated to it. (A naked model so to say)
The Tool Options
This option defines what shall happen with the original Mesh(es) (those which you have selected in Object mode)
- Delete: The Original Mesh is deleted.
- Hide: The Original mesh is kept but gets hidden. You can always unhide hidden objects with the keyboard shortcut ALT + H
- Keep: The Original Mesh is kept and remains visible. Thus the original and the new copy are displayed at the same time
As static Mesh:
If the original Mesh was rigged to an armature, then -by default- the frozen mesh Copies keep rigged as well. But sometimes you want to get a complete static statue with no animation information at all. In this case you will select this option.
Note: If you select this option you get an additional option Remove Weight Groups which does what the name implies. Hence you can achieve that the frozen object contains no animation data at all (this option is rarely used, but very handy when needed)
If you have selected 2 or more objects, then the Join Parts appears. This option just joins the frozen parts into one resulting mesh object.
Note: If the Join parts option is selected, then you get one more option Weld Parts. If that option is checked, then all duplicate vertices along the adjacent edges of the joined parts will be merged.
Weight Inspection Tools
Each Vertex of a Skinned Mesh can be controlled by multiple bones at the same time. While this is possible it is not always wise to do it, because with every new bone the overall behavior of the mesh becomes more and more complex.
The Inspect Weights tool creates a map for quickly spotting areas of Vertices with a high number of weights (number of influencing bones). You find this tool at the bottom of the Avastar Tools panel.
Usually it is fully sufficient to have one or 2 weights per vertex. Only in very rare cases 3 or 4 weights may be not avoidable.
The Inspect Weights function actually uses Vertex Painting to draw a color code right on the Mesh as seen in the image
In the above example you can see that most vertices of the Mesh are actually controlled only by one Bone (gray areas on the mesh in the image above). And you can see that typically only near the bone joints we find 2 weights on the vertices (green areas). For the SL Avatar we do not find any vertex with more than 2 Weights.
Note: Remind that each vertex has to show up in at least one weight map, otherwise you get an error “unweighted verts in mesh” when you try to import your mesh to SL or compatible worlds.