Sculpting organic shapes

Some things are about their form: a mouse that fits your hand, a toy, a handle, a soft lamp shade. Boxes, cylinders and fillets are the wrong tools for those. Sculpt lets you shape a smooth body the way you would shape clay: you move a few control points around it, and a smooth surface follows them.

The idea in one picture

A sculpted body has a control cage: a simple shape made of points, edges and faces that floats around the smooth surface. The surface is pulled toward the cage but stays smooth — move a point and the surface flows with it. A few points give a soft, rounded shape; more points (and sharpened edges) give more detail.

You never edit the smooth surface directly, only the cage. That's why it stays smooth whatever you do.

Start a shape

• ⌘K → "New organic shape…", or ask the agent ("a smooth computer mouse 120 mm long").
• Pick a starting shape: Blob, Capsule, Soft cube, Ring, Bottle, Mouse shell, Handle or Organic stand.

To change an existing one: the Sculpt button on its row in the Recipe, right-click the shape (context ring → Sculpt), or ⌘K → Sculpt….

Bodies grown from a skeleton

Animals, characters, figurines and branching shapes (a dinosaur with four legs, a neck and a tail; a teddy; a tree-like stand) start best from a skeleton: a stick figure the shape grows around. Each joint is a point with a thickness — how fat the body is there — and bones join the joints. The body grows as one smooth piece around it: tubes along the bones, rounded ends, and soft, seamless joins where several bones meet. No separate blobs glued together, no creases where a leg meets the body.

Ask the agent for one ("a cartoon dinosaur with a long neck and four legs, 160 mm long"), or hand it a concept. In the Recipe the step reads like Sculpted body from a skeleton · 10 joints, mirrored. "Mirrored" means you only describe one side; the other side is a mirror copy.

To change it:

• Ask the agent — "make the belly rounder", "a longer neck". It moves joints or changes their thickness, and the body stays a skeleton body.
• Sculpt it by hand — the Sculpt button opens it on the shape its skeleton grows. Changing the size or softness keeps the skeleton. As soon as you move points and finish, the step becomes a plain sculpted shape: the skeleton is set aside, and from then on you shape it like any other sculpt. A note says so when you open it, and ⌘Z brings the skeleton back.
• Joints can use parameters (a joint at -len / 2, a thickness of belly), so sliders can make the neck longer or the belly rounder.

A small limb drawn too close to the body — a snout, an ear, an arm starting in the middle of the chest — is moved out to the body's surface for you (a snout keeps how far it sticks out). If a skeleton still can't grow a clean body, the step says why in plain words — for example feet drawn inside the hips, or two branches leaving a joint in almost the same direction. Spread those joints apart or make them thinner.

Sculpt mode

While you sculpt, a toolbar sits above the prompt bar. Everything else stays where it is.

While a transform runs, press X, Y or Z to lock it to an axis (Shift + X/Y/Z: lock to a plane), and type a number for an exact amount — millimetres for moves, a factor for scale, degrees for rotation. With something selected you can also type the exact position of its centre in the row above the toolbar.

⌘Z / ⇧⌘Z undo and redo inside Sculpt mode. Enter finishes (one step in the Recipe, undoable like any edit), ✕ discards your changes.

What you see while you work

The surface you drag is an instant preview, so it follows the mouse smoothly. When you let go, the exact body is built — the status chip at the top left says Quick preview or Exact shape. The exact body is what exports, prints and gets checked.

Size sliders

New shapes get length, width and height parameters (turn this off in the toolbar's ⋯ menu). Drag them in Parameters and the whole shape stretches; holes and other features follow as usual.

Tips

1. Start simple. A blob with a handful of faces shapes better than a dense cage. Add detail only where you need it.
2. Pull out, don't push points one by one. Limbs, handles, feet, ears: select the faces where they grow from and press E.
3. Mirror early. Most products are symmetric: turn on Mirror X and you only shape half.
4. Sharpen sparingly. One sharpened loop of edges makes a crisp parting line or a flat bottom; sharpening everything gives you a box again.
5. Check the reflections. ⌘K → Check smoothness shows whether light flows over the shape (see Checking smoothness).
6. Printing: organic shapes often have no flat side. When the piece has none, a chip offers Add a flat base for printing — it cuts the bottom flat (1 mm by default; change it in the Recipe).

Flowing shapes

Bottles, vases, ducts and handles can also be made as a flowing shape: a smooth body through cross-sections along a path. Ask the agent ("a vase that goes from round at the bottom to square at the top"), then refine it with Edit flowing shape (the button on its Recipe row, or ⌘K): each section's position along the path, shape, size and turn, plus coral handles in the view to resize a section. Add section puts one in the widest gap.

Generated bodies

A detailed body generated from a concept sheet or photos (see Turning a concept into a detailed 3D body), or a mesh you imported, has no cage to sculpt. Sculpt… on such a piece says so and opens Mesh tools instead: shape sliders (stretch, grow, move or bend a part, like Neck length), smoothing, make symmetric, hollowing with drain holes and splitting for printing. Its length / width / height sliders resize it, and holes, pockets, bosses and text work on it like on any solid. See Working with meshes.

Classic and organic together

A sculpted body is a normal solid: you can drill holes into it, cut USB openings, add screw bosses, shell it, fillet where it meets other features, export STEP or STL, check printability and simulate it. Many products are exactly that — an organic outer form with precise features on top.

For CAD users: Sculpt is subdivision modelling (a SubD cage with the Catmull–Clark limit surface, semi-sharp creases and mirror symmetry), converted to an exact B-rep. A skeleton body is a skin-modifier / ZSphere-style cage generated from the joints on every build (an all-quad cage: 8-, 6- or 4-sided tube rings, a small capsule-like ball at each branching joint, mitred rings at bends, rounded caps), so it works with Sculpt mode's mirror editing. Turn on Pro terms to see those names in the app.