> For the complete documentation index, see [llms.txt](https://docs.imerit.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.imerit.net/3d-multi-sensor-fusion/labeling/3d-multi-sensor-fusion-labeling-editor/key-features/combined-tools-cuboid-3d-polygons-3d-polylines-+-2d-drawables.md).

# Combined Tools (Cuboid, 3D Polygons, 3D Polylines + 2D Drawables)

## Overview

The Multi-Modal Segmentation Tool is a new point cloud annotation capability that integrates three distinct segmentation methods - cuboid, polygon, and brush - into a single, unified workflow. Annotators can now apply the optimal tool for each geometric region of an object without switching contexts, losing progress, or accepting accuracy trade-offs.

Real-world objects are geometrically diverse. A vehicle has a rectangular body, an irregular roof rack, and ground-contact surfaces that each demand a different annotation approach. Until now, annotators were forced to pick one tool and compromise everywhere else - or spend excessive time applying the wrong method to each part.

## What's New

### Integrated Tool Switching

Annotators can now transition between cuboid, polygon, and brush modes within a single annotation session on the same point cloud object. No work is lost when switching modes, and all segments contribute to a unified output.

### Simultaneous Multi-Tool Operation

All three tools operate on the same point cloud simultaneously. Segments created by different tools are merged into a single, coherent annotated object, preserving geometric accuracy across every region.

### Contextual Tool Optimization

Each tool is designed for the annotation challenge it handles best. Cuboids provide fast, precise coverage of rectangular geometry. Polygons handle irregular outlines with accurate trace-based boundaries. Brush delivers pixel-level refinement for terrain contact and complex surface edges.

## Tool Reference

<table data-header-hidden><thead><tr><th valign="top"></th><th valign="top"></th><th valign="top"></th></tr></thead><tbody><tr><td valign="top">Tool</td><td valign="top">Best For</td><td valign="top">Use in Multi-Modal</td></tr><tr><td valign="top">Cuboid</td><td valign="top">Rectangular bodies, geometric shapes</td><td valign="top">Vehicle chassis, building facades</td></tr><tr><td valign="top">Polygon</td><td valign="top">Irregular outlines, complex contours</td><td valign="top">Roof racks, cargo attachments</td></tr><tr><td valign="top">Brush Sphere</td><td valign="top">Fine-detail refinement, terrain edges</td><td valign="top">Ground contact points, irregular surfaces</td></tr></tbody></table>

## Example Workflow

The following illustrates how the three tools work together when annotating a construction vehicle:

**Step 1 - Brush:** **+ icon (class level):** creates a new annotation instance. Tooltip: *"Add annotation"*. Always visible on the class row.

* **Pencil icon (annotation level):** edits an existing annotation. Tooltip: *"Edit with"*.
  * Clicking the pencil icon beside an annotation opens a palette labelled "Edit with" listing all drawables configured for that class.
  * Selecting a drawable enters add/remove-point editing mode for the existing annotation using the chosen tool.
  * If exactly one drawable is configured, the pencil icon activates it immediately without showing a palette.
  * The edit palette is sourced from the same project-setup configuration as the create palette. No hardcoded tool lists exist in either.

**Step 2 - Polygon:** **+ icon (class level):** creates a new annotation instance. Tooltip: *"Add annotation"*. Always visible on the class row.

* **Pencil icon (annotation level):** edits an existing annotation. Tooltip: *"Edit with"*.
  * Clicking the pencil icon beside an annotation opens a palette labelled "Edit with" listing all drawables configured for that class.
  * Selecting a drawable enters add/remove-point editing mode for the existing annotation using the chosen tool.
  * If exactly one drawable is configured, the pencil icon activates it immediately without showing a palette.
  * The edit palette is sourced from the same project-setup configuration as the create palette. No hardcoded tool lists exist in either.

**Step 3 - Cuboid:** Draw a cuboid around the vehicle's main rectangular body. Fast, precise, and ideal for geometric shapes.

* Leverage all cuboid features to get fast and accurate segmentation. Features that help reduce the time per object and enhance accuracy: interpolation, film reel, autogrounding, static dimension etc.

The result is a fully segmented point cloud built with the optimal tool for each geometric challenge - completed in one continuous workflow, with no context switching.

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## Configured Drawables

### Smarter Annotation Palette

* The drawable palette - the menu annotators use to choose their labeling tool - shows only the tools configured for the class being annotated.&#x20;
* When a class has only one tool configured, the palette is skipped entirely. The tool activates immediately and a brief confirmation strip tells the annotator which tool is active.

### Edit With Any Configured Tool

* Annotators can edit an existing annotation using any drawable configured for that class - not just the tool that originally created it. This means an annotation created with Polygon can be refined using Brush sphere, and vice versa, without needing to re-annotate from scratch.&#x20;
* The edit and create palettes are sourced from the same project configuration, ensuring consistency.

### Visually distinct create and edit actions

* The class list panel uses distinct icons to differentiate creating a new annotation from editing an existing one. The + icon creates. The pencil icon edits.&#x20;

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## Availability & Compatibility

**Availability:** This feature is generally available in the current platform release.

**Supported formats:** All standard point cloud formats currently supported by the annotation platform (pcd and las).

**Existing projects:** Fully compatible with existing annotation projects. No migration required.

**Access:** Available to all annotator roles. No additional permissions or feature flags required.

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## Why It Matters

As autonomous systems encounter increasingly diverse real-world objects - construction equipment, unusual vehicle configurations, complex urban structures - training data must capture geometric complexity accurately. Single-tool annotation workflows cannot keep pace with this diversity.

Multi-Modal Segmentation addresses this directly:

* Accuracy improves because each region is annotated with its geometrically appropriate method.
* Speed increases because annotators are no longer spending excessive time forcing the wrong tool onto a task.
* Workflow continuity is preserved - no saving, switching, or re-importing required between tool modes.
* Training data quality scales with object complexity, rather than being bottlenecked by it.
