# F08 — Tools Panel (Brush / Options)

> SkinLayer Studio **1.3.x Standalone** UI reference.  
> Practice: EP00–EP12 · Features: **F01–F17** (order 50+).

> Right-side **Brush / Options** area (layout **#9**) — tabbed work panel.  
> Placement: see the [UI layout guide](/guide/skin-layer-studio/ui-layout-overview?lang=en).

Tabs:

| Tab | Role |
|-----|------|
| **Set Weights** | Brush · Flood · Set Weights |
| **Tools** | Smooth Layer · Fallback · Residual |
| **Mirror** | Left/right (axis) weight mirror |
| **Export** | Skin Limit · Normalize/Prune · Remove Unused |
| **Scene** | Viewport colors · bone display |
| **Attribute** | Selected-target attributes (Geo / Dummy, etc.) |

---

> **What is this panel for?**  
> Brush, Flood, Fallback, Mirror, Skin Limit — how you paint and clean weights.  
> (Not the menubar Tools menu; this is the **lower-right panel**.)

## Set Weights

![Set Weights tab](tools_set_weights.png)

Default tab for painting. Pick a bone (or Mask) in Influences, then work in Paint mode.

### Brush projection

| Option | Description |
|--------|-------------|
| **Surface** | Brush along the mesh surface |
| **Screen** | Brush in screen (2D) space |

### Brush mode

| Mode | Hotkey | Description |
|------|--------|-------------|
| **Replace** | R | **Replace** selected bone weight with Intensity |
| **Add** | A | **Add** Intensity |
| **Sub** | D | **Subtract** Intensity |
| **Multiply** | M | Multiply (≥1 increase / below 1 decrease) |
| **Smooth** | S | Laplacian average of neighbors (Shift also temporary Smooth) |
| **Sharpen** | — | Disabled (future) |

### Brush shape

| Option | Description |
|--------|-------------|
| **Soft** / **Mid** / **Hard** | Edge falloff |

### Sliders · buttons

| UI | Description |
|----|-------------|
| **Intensity** | Max strength per stroke (0.00–1.00) |
| **SP** | Eyedropper — sample Intensity from a vertex click (I key) |
| **Brush radius** | Brush size |
| **Iterations** | Iteration count for Smooth, etc. |
| **Set Weights** | Apply current settings to selected vertices |
| **Flood** | Batch-apply current mode · Intensity to selection/target range |

> **Flood example:** Flood a Side layer at Replace 1.0, then Smooth the edge — common on skirts/flat areas.

---

## Tools

![Tools tab](tools_tools_tab.png)

| UI | Description |
|----|-------------|
| **Smooth Layer...** | Smooth weights/mask for a whole layer (dialog) |
| **Fallback Bone** | Bone that **receives residual weight** when sum < 1.0 |
| **Residual verts** | Scan result (`--` if not scanned) |
| **Scan Residual** | Scan vertices with sum < 1.0 |

Same Fallback as Influences `[Fallback: …]`. **Change it in this Tools tab combo.**

---

## Mirror

> **Mirror tab vs Layers → Mirror Layer**  
> - **Mirror tab**: mirror the **active layer** weights/mask (e.g. one arm → other).  
> - Layers **Mirror Layer (mask + inf)**: duplicate a whole layer L/R.

![Mirror tab](tools_mirror.png)

| Section | Description |
|---------|-------------|
| **Mirror Direction** | Axis · direction such as `+X→-X` |
| **Seam Width** | Width near the mirror plane |
| **Select** | Select vertices with `|axis| ≤ Seam Width` (Vertex mode) |
| **Smooth Iterations** | Seam smooth count (0 = hard mirror) |
| **Scope** | All vertices / selected vertices only |
| **Preview Bone Mapping...** | Preview L/R bone mapping |
| **Mirror** | Run mirror with current settings |

---

## Export

![Export tab](tools_export.png)

Despite the name Export, this tab is for **cleanup · limits before DCC export**. (Actual Apply to Skin is the top toolbar.)

### Skin Limit

| UI | Description |
|----|-------------|
| **Enable** + number | Max bones per vertex (e.g. 8). Applied on Apply to Skin |
| **Apply to All Meshes** | Store the same limit on all meshes (inside SLS) |
| **Select Over-Limit Vertices** | Select vertices over the limit |

### Layer cleanup

| Button | Description |
|--------|-------------|
| **Normalize Layer Tool** | Normalize layer dialog |
| **Prune Layer Tool** | Remove weak weights under threshold |
| **Remove Unused Influences** | Remove bones that are 0 on all vertices from Skin |

---

## Scene

![Scene tab](tools_scene.png)

Changes viewport **display only**. Does not change weight values.

### Viewport · Influence / Mask View

| | Wire Mode | Face Mode |
|--|-----------|-----------|
| **Influence (Weight)** | Wire weight color | Face weight color |
| **Mask View** | Wire mask color | Face mask color |

Common options e.g.: `Heatmap (Red/Blue)` · `White/Black` · `Density (Influence)`

**Reset** → restore Scene display defaults.

### Bone Display

| UI | Description |
|----|-------------|
| **Bone Radius Ratio** | Bone display thickness ratio |
| **Line Width** | Normal bone line width |
| **Selected Line Width** | Selected bone line width |
| **Bone Color** / **Selected Color** | Bone · selected bone color |

---

## Attribute

Contents change with the selection.

### Normal mesh (Geo)

![Attribute · Geo](tools_attribute_geo.png)

`Mesh: …` + *(normal mesh — no editable attributes)* — info only.

### Dummy

![Attribute · Dummy](tools_attribute_dummy.png)

When a dummy created via Hierarchy **Create Dummy**, etc. is selected:

| Section | Description |
|---------|-------------|
| **Shape (locked)** | Cylinder, etc. · Subdiv/Segment · Sides (read-only) |
| **Weight (locked)** | Type (e.g. IK) · Root Bone |
| **Adjust** | Editable params such as **Radius** |
| **Init Points** | P0… → bone name mapping · **[Edit]** to reassign bones |

---

## Recommended flow

```
1) Set Weights — paint bone weights
2) Tools — check Fallback · Residual Scan · Smooth Layer if needed
3) Mirror — copy L/R symmetry
4) Export — Skin Limit · Normalize/Prune · Unused cleanup
5) Scene — adjust heatmap/bone display
6) Attribute — when Dummy selected, adjust Radius · Init Points
7) Top Apply to Skin
```

---

## Related docs

| Doc | Contents |
|-----|----------|
| [UI layout guide](/guide/skin-layer-studio/ui-layout-overview?lang=en) | Tools location (#9) |
| [Influences details](/guide/skin-layer-studio/ui-influences?lang=en) | Paint target bones · Mask |
| [Bone Hierarchy details](/guide/skin-layer-studio/ui-hierarchy?lang=en) | Create Dummy · bone hierarchy |
| [Create Dummy · Transfer Weights](/guide/skin-layer-studio/ui-dummy-transfer?lang=en) | Create dummy → Transfer |
| [Layers panel details](/guide/skin-layer-studio/ui-layers?lang=en) | Active layer |

---

*Images: `tools_set_weights.png` · `tools_tools_tab.png` · `tools_mirror.png` · `tools_export.png` · `tools_scene.png` · `tools_attribute_geo.png` · `tools_attribute_dummy.png`*  
*Written: 2026-07-26*