# 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


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET 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?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.