Sculpt, unwrap and bake maps in Sculpt Lab

Sculpt Lab turns a simple mesh into a detailed sculpt and transfers that detail back onto the simple mesh as texture maps — the usual high-poly to low-poly workflow, on your device. It uses the same engine as the UV Unwrap (LSCM) for OBJ, STL and PLY and Normal Map & AO Baker (high → low poly) tools, so the files are identical.

Open Sculpt Lab

Choose Sculpt Lab in the toolbar. The lab opens with the Icosphere under Starting mesh; you can also pick Open cylinder, Box or Plane, or load your own file with Or open a mesh (STL, OBJ or PLY). Your file becomes the base mesh: the low-poly mesh that is unwrapped and receives the maps.

The view on the left is a 3D view. Pointer mode decides what dragging does: Orbit the view, Sculpt with the brush or Pick seam vertices. Shift-drag or right-drag always orbits. With the view focused, the arrow keys orbit, + and − zoom and 0 resets the view.

Subdivide before sculpting

Brushes move vertices, they do not add new ones, so give the sculpt enough vertices first. Under Sculpt mesh, keep Subdivision levels at 2 and choose Subdivide (Loop). The status reads Loop subdivision done; triangles to sculpt: 5120. Earlier strokes were replaced. and the line below the view shows Base mesh — vertices: 162, triangles: 320. Sculpt — vertices: 2562, triangles: 5120. Smooth everything (Taubin) relaxes the whole sculpt without shrinking it; Reset the sculpt goes back to the base mesh.

Sculpt

Under Brush, choose one of Draw, Inflate, Smooth, Flatten, Pinch, Grab and Crease, then set Brush radius, Brush strength and Falloff. Mirror across X is on by default, so every stroke is repeated on the other side of the model. Invert the brush turns Draw into carving and Pinch into spreading.

Set Pointer mode to Sculpt with the brush and drag over the model; a circle shows the brush size. Every stroke is one step for Undo stroke and Redo stroke. With the keyboard, focus the view in the same mode: the arrow keys move a brush cursor over the surface (Shift + arrow keys in larger steps), Space or Enter puts the brush down and lifts it again, Escape ends the stroke, + and − change the radius and [ and ] the strength; Alt + arrow keys orbit. A screen reader hears the cursor's vertex number and position, and every key stroke is one undo step, like a dragged stroke.

Without a pointer, use Apply without a pointer: type 1, 6 into Vertex numbers and choose Apply the brush at these vertices. With Draw and the default radius 0.42 the status reads Stroke applied; vertices moved: 378. With Grab, the first listed vertex moves by Grab offset x, Grab offset y and Grab offset z.

Unwrap the base mesh

Under UV unwrap, keep Cut at sharp edges (seam angle) and choose Unwrap the base mesh. A sphere has no sharp edges and no border, so the lab splits it: Unwrapped; charts: 2, mean angle error 2.77°. The Unwrap summary lists a Mean area distortion |ln(area ratio)| of 0.3336 and Distortion per chart shows area ratios from 0.513 to 2.63 — angles are kept, areas are not.

Switch Display to Base mesh with checker texture to see the squares on the model, or Base mesh charts to see each chart in its own colour. For your own seams, choose Pick seam vertices and click vertices on the base mesh; the path appears in Manual seams (vertex numbers). Download the result with Download the OBJ with UVs.

Bake maps

Under Bake maps, keep Map size (px) at 256 and Normal map and ambient occlusion, then choose Bake the sculpt onto the base mesh. The status reads Maps baked: 100 % of the rays hit the sculpt. If the share is lower, raise Cage distance (% of the model size). Pick DirectX (−Y: Unreal, 3ds Max) under Green channel for engines that expect it.

Each map has Download the normal map (PNG) or Download the ambient occlusion map (PNG) and Open in Texture Lab, which opens the map as a texture source for packing and previews. Download the sculpt (OBJ) keeps the high-poly mesh, for example for the baker tool.