---
title: "MapProjectionEvent | JavaScript maps SDK"
description: "Documentation for MapTiler SDK"
---

> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.

# Type Alias MapProjectionEvent

The map projection event

type MapProjectionEvent \= {  
    [newProjection](#newprojection): [ProjectionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ProjectionSpecification/)\[["type"](https://docs.maptiler.com/sdk-js/api-reference/types/ProjectionSpecification/#type)\];  
    [type](#type): "projectiontransition";  
}

##### Index

### Properties[](#properties)

[newProjection](#newprojection) [type](#type)

## Properties[](#properties-1)

### newProjection[](#newprojection)

newProjection: [ProjectionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ProjectionSpecification/)\[["type"](https://docs.maptiler.com/sdk-js/api-reference/types/ProjectionSpecification/#type)\]

Specifies the name of the new projection. For example:

-   `globe` to describe globe that has internally switched to mercator
-   `vertical-perspective` to describe a globe that doesn't change to mercator
-   `mercator` to describe mercator projection

### type[](#type)

type: "projectiontransition"