Mesh deform

Warp a Shape or an image over a triangulated cage, bound to bones the same way a Shape's own points are.

A Mesh layer wraps a texture in a triangulated cage: move the cage's vertices and the artwork inside follows. Where binding a Shape's own points works point by point (see Binding and weights), a mesh gives you a cage independent of the drawing's own path, which is useful for artwork, an imported image especially, that does not have enough of its own points to bind directly.

Creating a mesh#

Add Layer ▸ Mesh creates an empty mesh container. More often you will wrap an existing layer instead: right-click an Image layer and choose Add Mesh Parent, or right-click a Shape layer and choose Convert to Mesh.

Grid vs. drawn mesh#

The Mesh section of the Properties panel, visible only in Edit mode, gives you a Grid of columns and rows (1 to 40 each, 8×8 to start) and a Rebuild Grid button that lays an evenly-spaced cage of that resolution over the layer.

For a cage that follows the artwork's own silhouette instead of a plain rectangle, draw the outline by hand with the Pen tool. On a Mesh layer the Pen switches to drawing mesh vertices and edges directly rather than a bezier path; turn on Line Mode in its options bar to only connect existing points into edges without dropping new ones. Celas Studio triangulates the drawn outline to fit its actual shape, not its convex hull, and keeps any edges you drew as constraints in that triangulation.

Where the weights live#

A mesh does not keep its own separate weight data. Its vertices are weighted to bones through the exact same storage a Shape's points use, just addressed by the mesh's vertex index instead of a Shape's vertexId. That means every weighting tool works on a mesh exactly as it does on a Shape: Auto Weight, the weight area, Weight Paint, Mirror Weights, and Bind and Unbind, which reach mesh vertices through the Bone Bind tool. That tool draws the mesh cage as well as its vertices, so you can see what you are binding rather than picking dots floating over the artwork. See Binding and weights and Weight painting for how to use them.

Animating a mesh#

A bound mesh deforms automatically as its driving bones move, the same skinning a Shape's points get. On top of that, you can pose the mesh directly: switch to Animate mode and drag its vertices with the Node tool to bend it beyond what the skeleton alone gives you. The cage is drawn where the rig has actually put it, so on a posed rig a vertex lands under the cursor and clicks where you see it. With Auto-Key on, releasing the drag records a keyframe for that pose; with Auto-Key off the pose is temporary and disappears the moment the playhead moves.

Edit mode always shows the mesh's undeformed rest pose, regardless of what you have keyed, which is deliberate, so you can always get back to a clean cage to adjust its resolution or its bind without fighting your own animation.

Limits#

A mesh follows the rig that actually binds it, so a project with more than one Bone layer can drive different parts of a scene from different armatures. The Bone and weight tools still work on the first Bone layer they find, which is the remaining reason to keep a project simple in Early Access; see Bones basics.