Wednesday, August 26, 2020

DAZ Studio bones

Update 

With the help of engetudouiti the bones are now oriented correctly even when the mesh is posed in DAZ Studio. Compare a posed Aiko from yesterday and from today.

Since this means that the Apply Morphs and Copy Bones buttons are no longer frequently needed, they have been relegated back to the Advanced Rigging section. The Use Clothes Bones option of the Merge Rigs button was also removed for the same reason

 

Original post

The way the Daz Importer creates bones in Blender has been slightly different from how the bones are oriented in DAZ Studio. The Blender bones go from the bone's center point (head or pivot point) to the bone's end point. However, in DAZ Studio the end point is a handle to grab the bone, and not necessarily located along the direction of the bone. Although usually it is, which is the reason why the end point works quite well as bone tail. In fact, I would not have noticed the difference, unless frequent commenter engetudouiti had pointed it out.

In version 1.5 of the plugin, the default bone orientation has been changed to conform with the orientation in DAZ Studio.

You can choose the method used for bone orientation in the Rigging section of the Global settings dialog. There are three alternatives.

  • Blender Legacy: The old method where bones end in the end points. This still works as it always has.
  • DAZ Unflipped: The bones are oriented exactly the same way as in DAZ Studio, apart from a 90-degree rotation in world space (can be turned off by disabling Z Up). This mode is for debug purposes only, since bones in DAZ Studio don't have to be point in the local Y direction.
  • DAZ Studio: The bones are oriented as in DAZ Studio, followed by a set of 90-degree rotations which shift the local coordinate axes.

Here we have imported Aiko, who is the heroïne of the 1.5 documentation, using the three different methods for bone orientation. The armatures to the left and right look quite similar, but there are some differences.

If the character was imported with Mesh Fitting = DBZ File, Aiko's feet fit into her sandals, but her foot bones do not. This is just how the information is stored in the .duf file. The orientation of the body feet bones (red) are the same as in the rest pose, whereas the sandal feet bones (blue) have a different orientation. We want the bones of the merged rig to be like the blue bones. This is done with the Copy Bones tool, which copies the bones in edit mode from the selected rig to the active one.

If Aiko was imported with Mesh Fitting = Unmorphed Shared or Unique, the foot appears to fit into the sandal. However, this is an illustion because the foot is posed; the rest pose is still standing on the soles.