# Selection Controls

> Viewport selection controls in Asset Transformer Studio

[Parts](../../../data-preparation-fundamentals/about-occurrences/occurrence-types) present in the scene can be selected directly from the viewport.

To select parts, use the following controls:

## Single-click selection

![Single-click selection](/api/media?file=/asset-transformer-studio/2026.5.0/media/STUDIO_Selection-Click.gif)

|                                                                            | Combinations               | Description                             |
| -------------------------------------------------------------------------- | -------------------------- | --------------------------------------- |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem4.png) | `Left-click`               | Select / Replace occurrences            |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem6.png) | `CTRL Key` + `Left-click`  | Add / Remove from the current selection |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem5.png) | `SHIFT Key` + `Left-click` | Remove from the selection               |

## Area selection

An Area selection is when the user draws a selection rectangle (mouse drag) in the viewport.

Use the following controls to select parts with Area selection:

|                                                                             | Combinations                                                | Description                                                                                                                        |
| --------------------------------------------------------------------------- | ----------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem14.png) | `Left-click` + `Selection area`                             | Select **only** occurrences visible from the camera view and crossed by the selection rectangle                                    |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem71.png) | `CTRL Key` + `SHIFT Key` + `Left-click` + `Selection area`  | Add to the current selection **only** occurrences visible from the camera view and crossed by the selection rectangle              |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem73.png) | `SHIFT Key` + `Left-click` + `Selection area`               | Remove from the current selection **only** occurrences visible from the camera view and crossed by the selection rectangle         |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem15.png) | `Right-click` + `Selection area`                            | Select **all** occurrences from the scene crossed by the selection rectangle (**"in-depth" selection**)                            |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem72.png) | `CTRL Key` + `SHIFT Key` + `Right-click` + `Selection area` | Add to the current selection **all** occurrences from the scene crossed by the selection rectangle (**"in-depth" selection**)      |
| ![](/api/media?file=/asset-transformer-studio/2026.5.0/media/NewItem74.png) | `SHIFT Key` + `Right-click` + `Selection area`              | Remove from the current selection **all** occurrences from the scene crossed by the selection rectangle (**"in-depth" selection**) |

> **Important:**
>
> "In-depth" selection with the Mouse Right-Click will select all the parts comprised in the selection rectangle, **including occluded parts** (meaning entirely hidden by other parts). Contrary to selection with the Mouse Left-Click that **will not select occluded parts**.

> **Note:**
>
> All parts crossed by the selection rectangle will be selected: they do not need to be entirely in the rectangle to be selected (one pixel is enough).