Bone Bind / Weight Paint tool

Bind vertices to a bone by hand, or paint how strongly each vertex follows it.

The Bone Bind / Weight Paint tool (Shift+J) needs a Bone layer with at least one bone in it: with none, the tool does nothing. It works on the rig of the selected layer: the selected Bone layer, or the Bone layer the selected layer sits in. With no such layer selected, it works on the rig whose bone is picked, otherwise on the first Bone layer. Bind reaches the vertices of any editable Shape or Mesh layer, so you do not need to select the layer you are binding; you just need its vertices, and it needs to be editable.

Bind mode#

With Weight Paint turned off, the tool works vertex by vertex: click near a bone to select it, click near a vertex on any editable layer to select it too: Shift adds more, otherwise the click replaces the vertex selection. Dragging an empty area marquees vertices, but only on layers already part of the layer selection.

Auto Weight distributes smooth weights automatically, with up to four bones influencing each vertex. It works on the shapes that own your selected vertices, otherwise on the selected layers, and with only the rig selected on the rig's own artwork. Weight Area sets the selected bone's reach: how far it moves artwork that follows the rig by itself, and how far Auto Weight lets it reach. Changing it writes no weights. See Binding and weights.

Link Layer rigidly attaches a whole layer to one bone's motion, as a shortcut for cases that do not need per-vertex weighting; the button relabels itself to Unlink once a layer is linked.

Weight Paint mode#

Turn Weight Paint on to paint influence with a brush instead of binding vertices one at a time. Every editable vertex is shown as a heat-mapped dot, from blue at zero weight to red at full weight, so you can see the result as you paint.

The brush paints only the selected layers, and a selected group brings the layers inside it. With only the rig selected, it paints the rig's own artwork: the Shape and Mesh layers inside the Bone layer and the shapes already bound to it.

Hold Alt to erase weight for a stroke regardless of the Weight / Unweight setting. A pen's pressure scales the strength as you paint; a mouse always paints at full strength. Mirror Weights copies each bound vertex's weight onto its mirrored vertex, matched by bone name: a bone named with a .L suffix mirrors to its .R counterpart.