> ## Documentation Index
> Fetch the complete documentation index at: https://docs.biom.science/llms.txt
> Use this file to discover all available pages before exploring further.

# Pane System

> Split your workspace into multiple independent viewers.

# Pane System

Relay uses a tree-based multi-pane layout that lets you view and compare multiple images simultaneously. Each pane operates independently with its own camera, adjustments, and annotations.

## Splitting panes

You can split any pane horizontally or vertically:

1. Hover over a pane to reveal the split controls
2. Click the horizontal or vertical split button
3. The pane divides into two independent viewers

### Constraints

| Limit                 | Value    |
| --------------------- | -------- |
| Maximum panes per tab | 6        |
| Maximum nesting depth | 4 levels |
| Split ratio range     | 5%–95%   |

## Pane types

| Type                 | Description                                            |
| -------------------- | ------------------------------------------------------ |
| **Canvas**           | Image/video viewer — the default pane type             |
| **Pipeline Builder** | Visual pipeline editor for building analysis workflows |
| **Table**            | Tabular data viewer for CSV, TSV, and JSON files       |
| **Slides**           | Deck/card presentation view                            |
| **Gallery**          | Grid view for browsing folders of images               |

You can switch a pane's type from the pane header menu.

## Pane isolation

Each pane maintains fully isolated state:

* **Camera** — independent pan, zoom, and rotation
* **Active image** — each pane can show a different file
* **Channel settings** — per-pane channel visibility, colors, and contrast
* **Annotations** — per-pane annotation visibility
* **Image adjustments** — independent brightness, contrast, gamma
* **Tool state** — active tool, selection, processing overlays
* **Comments** — per-pane comment visibility

This means you can view the same image in two panes with different channel configurations, zoom levels, or Z-slice positions — useful for comparing different aspects of the same dataset.

## Pane operations

| Operation        | Description                                    |
| ---------------- | ---------------------------------------------- |
| **Split**        | Divide a pane horizontally or vertically       |
| **Close**        | Remove a pane from the layout                  |
| **Resize**       | Drag the divider between panes to resize       |
| **Move**         | Drag and drop panes to rearrange them          |
| **Duplicate**    | Clone a pane with its current viewport state   |
| **Maximize**     | Expand a pane to fill the entire workspace     |
| **Link cameras** | Sync pan/zoom across multiple panes            |
| **Change type**  | Switch between canvas, table, pipeline builder |

### Pane header controls

Hover over a pane to reveal the header bar:

* Drag handle for rearranging panes
* Split horizontal / vertical buttons
* Duplicate pane button
* Maximize / minimize toggle
* Camera link / unlink button
* Active filename display
* Close button (when more than one pane exists)

## Drag and drop

You can drag and drop content into panes from multiple sources:

* **Files** from your desktop or file manager
* **Relay Drive files** from the sidebar file browser
* **Database assets** (Zarr, NWB) from the Databases tab
* **Pipeline definitions** from the pipeline library
* **Tabular files** (CSV, TSV, JSON) — opens in table pane
* **Cards** from the deck sidebar

When you drop a file, Relay auto-detects the file type and loads the appropriate viewer.

### Drop behaviors

* **Drop on empty pane** — loads the file in that pane
* **Drop on occupied pane** — shows split-zone overlay (left/right/top/bottom quadrants) to split and load
* **Alt + drop on occupied pane** — adds the image as an overlay layer instead of replacing (up to 8 layers)
* **Drop multiple files** — splits into N new panes, one per file

## Multi-tab system

Relay supports multiple tabs, each with its own pane layout:

* Create new tabs for different analyses or datasets
* Each tab persists its layout in IndexedDB
* An LRU cache keeps the 3 most recent tabs mounted for performance
* Switch between tabs without losing your viewport state

## Gallery mode

Gallery mode provides a grid view of all images in a folder:

1. Right-click a folder and select **Open as Gallery**
2. Each image loads in its own pane arranged in a grid
3. Use pagination to navigate through large folders
4. Exit gallery mode to restore your previous pane layout