Sketch and Extrude#
Create 3D solids from 2D constrained sketches. This is the parametric modeling workflow: draw a 2D profile, add geometric constraints, solve, then extrude into a 3D solid.
Quick Start: Rectangle Extrude#
The fastest way to create a parametric solid:
- Switch to the Sketch tab (click dock button or press S)
- Set W and H for your rectangle dimensions
- Click Rect — creates a fully constrained rectangle
- Set extrude height and click Extrude
A new 3D box appears in the scene, created from the constrained 2D sketch.
Full Sketch Workflow#
1. Begin Sketch#
- Select a sketch plane: XY, XZ, or YZ
- Click Begin Sketch to enter sketch mode
2. Add Points#
- Enter x and y coordinates
- Click +Pt to add each point
- Points appear in the dropdowns for edges and constraints
3. Add Edges#
- Select two points from the P0 and P1 dropdowns
- Click +Edge to connect them
- Edges appear in the constraint edge dropdowns
4. Add Constraints#
Select a constraint type from the dropdown. The UI shows/hides relevant fields based on the type:
| Constraint | What it does | Required fields |
|---|---|---|
| Fixed | Pin a point to exact (x, y) | Point, x value, y value |
| Horizontal | Force an edge to be horizontal | Edge |
| Vertical | Force an edge to be vertical | Edge |
| Distance | Set distance between two points | Two points, value |
| H-Distance | Set horizontal distance between points | Two points, value |
| V-Distance | Set vertical distance between points | Two points, value |
| Coincident | Make two points overlap | Two points |
| Parallel | Make two edges parallel | Two edges |
| Perpendicular | Make two edges perpendicular | Two edges |
| Equal Length | Make two edges the same length | Two edges |
| Midpoint | Place a point at the midpoint of an edge | Edge, point |
5. Solve (Preview)#
Click Solve to run the constraint solver and preview the solved point positions. The status bar shows the solved coordinates.
6. Extrude#
- Set the extrude height (distance along the plane normal)
- Click Extrude to create the 3D solid
- The sketch is consumed and a new solid appears in the scene
- Requires at least 3 edges forming a closed loop
7. Cancel#
Click Cancel Sketch or press Escape to discard the active sketch without creating a solid.
Keyboard Shortcuts#
| Key | Action |
|---|---|
| S | Switch to Sketch tab |
| Escape | Cancel active sketch |
Tips#
- Closed loop required: Edges must form a closed polygon (each point connected to exactly 2 edges) for extrude to work.
- Over-constraining: Adding too many constraints may cause the solver to produce unexpected results. Start with fixed + horizontal/vertical + distances.
- Quick Rect: The rectangle helper auto-creates 4 points, 4 edges, and 7 constraints (fixed origin, H/V edges, distances). It’s the easiest way to start.
- Multiple sketches: Each extrude creates an independent solid. You can add primitives and sketch-extruded solids in the same scene, then combine them with boolean operations.
Automerge Collaboration#
Sketch extrude operations are stored in the Automerge op log as sketch_extrude operations. When a collaborator extrudes a sketch, the full sketch JSON is replayed on your side to produce the same solid. This means sketches are fully collaborative — the constraint solving and extrusion happen independently on each peer.