Material Tools Window

The Material Tools window is where you choose which of the model's materials the next step works on. Open it from Window → Material Tools. It also opens on its own when you start a remesh, and when an action needs a material chosen first on a model that uses more than one (the status bar then reads “Select a material in Material Tools first.”). The window is dockable and remembers its size.

Loaded Mesh or Generated Mesh

The dropdown at the top switches between Loaded Mesh (the imported model's own materials, where you group, hide, delete and pass through) and Generated Mesh (whichever of those materials currently make up the created topology). It is the same switch as the sidebar's View: Loaded Mesh / View: Generated Mesh button — changing either changes both. It stays on Loaded Mesh until a topology has been created.

The Materials list

Each row is one material, with the number of polygons it is assigned to in parentheses. Materials that own no polygons are left out, and a material that belongs to a group is shown only through that group (see Merged Groups). Once a material has been handled, its row carries a badge: [Remeshed], [Passed Through], or [Mixed] for a group whose members were handled in different ways.

Clicking a row selects that material's polygons. The selection is what retopology, Pass Through, UV mapping and baking act on, and it also filters the Image Viewer to the selected materials' own wireframe and texture pixels. Hovering a row highlights its polygons in the viewport.

Click	What it does
Click	Selects this material alone. Clicking the only selected material again clears the selection.
Ctrl+click	Adds the material to the selection, or removes it if already selected.
Shift+click	Selects every row between the last clicked row and this one, keeping what is already selected.
Alt+click	Solos the material: shows it and hides every other material in the list.

Each row also has three icons:

Control	What it does
Eye	Hides or shows the material's polygons in the viewport. Visual only — a hidden material is still selectable and paintable.
Pencil	Opens Edit Material on this material, to change its name and properties with a live viewport preview. Vertexix and Ultra only; disabled in other editions.
Trashcan	Permanently deletes the material and its polygons from the loaded mesh, after a confirmation.

Merge Selection and Pass Through

Two buttons sit under the list, both disabled until at least one material is selected:

Control	What it does
Merge Selection	Groups every selected material into one named group. A prompt asks for the name and offers Merge Points, which welds vertex points on the group's geometry so separately authored parts become one continuous surface for retopology: Automatic merges points with exactly the same coordinates, Fixed Distance merges every point within a distance you type, in um, mm, cm or m.
Pass Through	Copies the selected material(s) or group straight into the created topology unchanged, skipping retopology for them entirely. Use it for parts that are already clean or low enough in polygons.

Both are covered in more detail on Merge Selection & Pass Through.

Merged Groups

Once a group exists, a Merged Groups list appears under the buttons, with the group's total polygon count and status badge. Click a group to select every material in it; click it again to clear the selection.

Control	What it does
Pencil (Edit selection)	Adds or removes this group's materials. The group's materials reappear in the Materials list; change the selection there, then press Save Changes to keep it as the group's new membership, or Cancel.
Tag (Change Group Name)	Renames the group. The same prompt offers Merge Points for the group's current members.
Trashcan	Deletes the group. Its materials become individually selectable again.

See Merged Groups Management for more.

Generated Mesh view

With Generated Mesh chosen, the window lists Materials in Generated Mesh: every material present in the created topology, each with its own row even if it belongs to a group, and the polygon count on the created topology. A -UV suffix marks a material that has a UV map there. Clicking selects and highlights its polygons, with the same Ctrl, Shift and Alt clicks as the Loaded Mesh list.

Control	What it does
Eye	Hides or shows the material's polygons on the created topology (visual only).
Pencil	Opens Edit Material on the same material the Loaded Mesh list edits, with a live preview on the created topology too.
Trashcan	Removes the material's polygons from the created topology only, after a confirmation. The material stays in the loaded mesh and can be retopologized or passed through again. Any UV map and baked textures on the created topology are cleared.

Below it, Groups in Generated Mesh lists every group whose materials are all present in the created topology. Click one to select all its polygons; its eye and trashcan work on the whole group the same way.

Material Properties

The Material Properties accordion shows, read-only, every parameter that changes the selected material's surface. Select exactly one material to fill it. Two collapsible sections follow the table: Mesh inputs (whether the mesh has vertex colors, and its UV channels) and All properties (raw), the complete list as the file stored it. See Material Properties Inspector.

UV Sets (UDIM)

UV Sets (UDIM) lists each UDIM tile the loaded mesh's UVs occupy, with its tile number. Each tile bakes to its own texture. Click a set to select its materials. The pencil assigns the set to a different tile, and the split icon gives every material in the set a tile of its own. With Generated Mesh chosen, only sets whose materials are in the created topology are listed. See UDIM Tile Manager.