> For the complete documentation index, see [llms.txt](https://doc.playturbo.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.playturbo.com/playable-tools-content-editor/content-editor-user-guide/editing-page-module-intro/work-preview-area/canvas-ruler-and-reference-line.md).

# Canvas ruler and reference line

During the editing process, the canvas ruler and reference line are convenient for asset and position alignment.

<figure><img src="/files/qMhK3WfmyWgwL0HB1k7T" alt=""><figcaption></figcaption></figure>

## 1.Add reference line

* Move your mouse near the canvas ruler area to bring up the reference line
* Left-click to successfully locate the reference line
* Drag the reference line to change its position

## 2.delete reference line

* Click the "×" button to delete the reference line

## 3.Auto-reference line

* Select the layer and drag it to the edge of the canvas to automatically activate the smart reference line
* Auto-reference line facilitates the edge alignment and position alignment of the asset