Is there a standard gesture for resetting scale on a pinch-zoom canvas?

1. What happens when you pinch to zoom?
2. How to use pinch gesture recognizer in Swift?
3. How to pinch zoom in JavaScript?

What happens when you pinch to zoom?

Pinch to zoom in on content:

In full screen mode, touch the video with two fingers. Move your fingers away from one another, while touching the video screen. Once you let go, the video will play at the new zoom level.

How to use pinch gesture recognizer in Swift?

A pinch gesture recognizer reports changes to the distance between two fingers touching the screen. Pinch gestures are continuous, so your action method is called each time the distance between the fingers changes. The distance between the fingers is reported as a scale factor.

How to pinch zoom in JavaScript?

The simplest way is to respond to the 'wheel' event. You need to call ev. preventDefault() to prevent the browser from doing a full screen zoom. Browsers synthesize the 'wheel' event for pinches on a trackpad, and as a bonus you also handle mouse wheel events.