How nodes work

In Forge you never edit a model directly. Instead you describe how to build it, as a chain of small steps called nodes: make a box, raise panels on it, round its edges, paint it. Forge runs the chain and shows you the result, and when you change any step, everything after it updates on its own.

If you write code, a node will feel familiar: it is a function. Geometry comes in, its parameters are the arguments, and new geometry comes out. A graph is those functions chained together. Like a pure function, a node never changes its input; it hands a new result on to the next node.

What a node is

A node does one job. On the canvas it is a small box with three parts:

• Inputs: the pins where geometry comes in from other nodes. A node that makes geometry from nothing, such as Cube, has none. Some inputs are optional, and the node works without them.
• Output: the pin where the node’s result comes out. Every node has exactly one, and you can wire it into as many other nodes as you like.
• Parameters: the node’s settings, such as how big a bevel is or how many edge loops to cut. Select a node to see them in the parameter panel, and hover a parameter’s name to read what it does.

The colored bar along the top of a node shows its family, in the same color as its section of the add-node menu. Every node’s page in this reference lists its inputs, output and parameters; Bevel is a good example.

What flows between nodes

Wires carry geometry from one node’s output to another node’s input. Every pin has a type, and its color tells you which:

• Mesh: a 3D surface, made of points joined into faces. Most nodes take a mesh and give one back, and a mesh is what you export to your game engine.
• Curve: a line or path through space, with no surface. Draw one with the Curve node, then sweep a shape along it, fill it into a flat face, or place copies along it.
• Scene: a whole model loaded from a file with the Import node: every mesh, material and texture in it, kept as it was.

A few nodes, such as Transform and Mirror, work on more than one type: they give back the same type you wire in. Their pins are blue, like a mesh.

Three rules decide what can connect:

• A wire only joins pins of matching types, so a curve cannot go into a node that needs a mesh. The editor will not let you drop it there.
• Each input takes one wire. Wiring into an input that already has one replaces the old wire.
• One output can feed many inputs, so a single shape can branch into several versions.

From nodes to a workflow

A workflow is a chain of nodes, read along the wires from first to last. Each node picks up the result of the one before it, does its job, and passes its own result on. Forge calls running a node cooking. Here is a simple crate:

1. Cube

   Start with a box.

2. PolyExtrude

   Raise a panel on every side.

3. Bevel

   Soften the sharp edges.

4. Smart UV

   Unwrap it, ready for paint.

5. Paint Fill

   Paint it.

Most workflows run in the same order the add-node menu groups its nodes: Create a starting shape, Shape it, add Detail, then Texture it. Utility nodes (moving, combining, naming parts of a mesh) fit in anywhere.

See any step

The viewport shows one node’s result at a time: the node whose display flag is on, the blue strip down its right edge. Click another node’s display flag to see the chain at that step, for example to check the shape before the bevel. To keep a second result in view, click its pin flag, just left of the display flag; each click cycles it through a solid mesh, a wireframe, both, and off.

Change your mind at any time

Every step stays editable. Go back to the Cube and make it taller, and the panels, the bevel, the UVs and the paint all follow, with nothing to redo by hand. Only the nodes that lead to what you are viewing cook, and steps you did not change are reused, so edits stay quick.

Branch and combine

A graph does not have to be a straight line. Wire one output into two nodes to try two versions side by side. Nodes with more than one input bring chains back together: Merge puts several meshes into one, Boolean cuts one shape out of another (or joins them), and Sweep runs a profile curve along a path curve.

Work on part of a mesh

Many nodes can act on just part of a mesh. Name the part with a Selection node, for example “every face pointing up” or “these three edges”. The name then travels with the mesh through the wires, with no extra wire to draw. Any later node with an Apply to setting, such as Bevel, PolyExtrude or Delete, can pick that name and work only there.

Warnings

A node that cooked but wants your attention (say, it looks for a selection name that no longer exists) shows an amber ! badge. Hover the badge to read why.

Export

When the model is done, Mesh ▸ Export glTF… saves what the viewport shows (the displayed node, plus any pinned ones) as a .glb file for Unity, Unreal, Godot or any engine that reads glTF.

Building a graph

• Add a node: right-click an empty spot on the canvas and type its name.
• Wire two nodes: drag from one node’s output pin to another node’s input pin.
• Put a node into an existing wire: right-click the wire.
• Cut a wire: hold Alt and click it.
• See every shortcut: Help ▸ Commands.

Node families

Every node has its own page, grouped into the same five families as the add-node menu:

• Create (geometry from nothing): Blockout, Cube, Grid, Curve, Sweep, Fill Curve, Import, Reference Figure.
• Shape (reshape geometry): PolyExtrude, Bevel, Remesh, Subdivide, Loop Cut, Delete.
• Detail (form and combination): Noise, Boolean, Edge Damage.
• Texture (UVs, paint and bake): Smart UV, Paint Fill, Paint Masked, Height Map, Bake.
• Utility (plumbing): Transform, Merge, Mirror, Selection, Ray, Inflate, Polyreduce, Place at Points, Curve Points, Trim Curve, Portal.

Note

The docs are written one family at a time. Families and nodes without a link are still being written.