Difference between revisions of "Linden Lab Official:Map API Introduction"

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==What is the Map API?==


Extend the reach of your Web site into Second Life using the ''Second Life Map API'', which enables you to embed interactive Second Life maps directly into your web pages. These maps look and act much like Google Maps, except that, instead of the Earth, they display the topography of the Second Life virtual world. See http://maps.secondlife.com/ for an example.
== Getting Started ==


When you use the Map API to embed Second Life maps on your site, your visitors can:
The Second Life Map API is a JavaScript library to embed Second Life maps onto your web pages.  It's a purely client-side JavaScript API.  If needed, you can also [[#Accessing_map_images_directly|directly access]] the map images.


* Click and drag the mouse pointer to pan the map view up, down, left, and right.
'''NOTE:'''
* Double-click to zoom in by one level (power of two) and display the teleport window.
This API is still in beta.  URLs and API signatures may change.  See the [[#Release notes|Release Notes]] for information on new features and known issues.
* Click anywhere on the map to open a "teleport" window.
* Use the mouse wheel or pan controls to zoom in and out.


For more information, see the [[Map API]] documentation.
=== Map UI features ===
| {{:Web Services Portal/navigation}}
|}


==What is DirectSLurl?==
The Map API enables you to create web pages that have web map functionality, using maps of Second Life, rather than Earth.  In general, the default map interface looks as shown here.


[[Using Second Life URLs (SLurls)|DirectSLurl]] is a web-to-inworld URL that teleports users to a specified Second Life location when they click on a special web-based URL, known as a SLurl. If the user has already installed the Second Life Viewer, then the Viewer starts and they are automatically given a dialog box to teleport to the location specified by the SLurl. If the user doesn't have an account, they are sent to the Second Life registration page; when they complete registration, download, install, and run the client, they automatically start at the location specified by the SLurl. DirectSLurl is an easy way to bring people to your location in Second Life without the programming requirements of the [[Registration API]]. You don't even need to use the [[Map API]] to take advantage of DirectSLurl, though you can use both for a more customized user experience. For more information, see Using Second Life URLs (SLurls) on the Second Life Wiki.
[[Image:Map ui cropped.png|right]]


==Terms of Use==
The main map display area shows the current map area.  By default, the map provides the following features:


All participants in Linden Lab's API program must abide by the [[Linden Lab Official:API Terms of Use|API Terms Of Use]].
* Click and drag the mouse pointer to pan the map around.
* Double-click to zoom in by one level (power of two).
* Click anywhere on the map to open a "teleport" popup (see '''Teleport popup''' below).
* Use the mouse wheel to zoom in and out.  See [[#Zoom_levels|Zoom levels]] for more information about zoom levels.
* Use the zoom controls at upper left to zoom the view in and out.
 
<br clear="all" />
 
'''Teleport popup'''
[[Image:Teleport window.png|left]]
Clicking anywhere on the map opens a popup (left) where you click.  Click "Visit this location" to start the Second Life Viewer & teleport you where you clicked.  This feature is implemented with the [[Map_API_Reference#Global_functions|gotoSLURL()]] global function.
 
<br clear="all" />
 
=== Working examples ===
 
See [[Map API Basic Examples]] for a detailed explanation of the working examples at http://maps.secondlife.com/examples/.
 
<span id="Using slurl.com and DirectSLurl"></span>
=== Using web links ===
 
The [http://maps.secondlife.com/ web site] uses the Map API to provide a mechanism to teleport directly to locations in Second Life from web pages.
 
For more information, see [[Using Second Life URLs (SLurls)]].
 
=== Include the API files ===
 
To use the Map API, put the following lines at the beginning of each HTML page.  This includes the JavaScript & CSS so that you can create the map & display it correctly.
 
<pre>
<!DOCTYPE html>
<html><head>
    <meta charset="utf-8">
 
    <script src="http://maps.secondlife.com/_scripts/sl.mapapi2.js"></script>
    <link rel="stylesheet" type="text/css" href="http://maps.secondlife.com/_styles/sl.mapapi2.css">
 
    ...
</pre>
 
All the examples also require additional script statements in the HTML header.
 
'''Stylesheet'''
 
You can also include your own stylesheet to style the other elements of your page. For example:
 
<pre>
    <link rel="stylesheet" type="text/css" href="http://maps.secondlife.com/_styles/sl.mapapi2.css">
    <link rel="stylesheet" type="text/css" href="myStyleSheet.css">
</pre>
 
=== Browser compatibility ===
The Map API has been tested to work with the following browsers:
* Internet Explorer 6.0
* Internet Explorer 7.0
* Firefox 2.0 or greater
* Safari 2.0
 
Other browsers may work but little issues may appear. Unless otherwise noted, all features work in all supported browsers.
 
=== Comments and feedback ===
 
If you encounter problems or bugs or have feature requests, please email '''webmap@secondlife.com'''.
 
Happy coding from the Second Life Web team!
 
== Basic concepts ==
 
The Map API is built around [http://leafletjs.com the Leaflet web map library]. Leaflet provides many options, methods & events for customizing the presentation of your Second Life map.
 
===About coordinates===
 
Map coordinates are based on the Second Life grid system for positioning regions.
 
[[Image:Webmap coords.jpg]]
 
As illustrated in the diagram above, the Map API maps the Second Life world to the upper right quadrant of an earth map.  A large scaling value equal to 2<sup>20</sup> or 1,048,576 defines the largest region coordinate at the top and far right edge of the displayed area.  This value creates a map area with room for one trillion sims.
 
The little blue square illustrates where the populated sims are in Second Life.
 
=== Zoom levels ===
There are eight zoom levels: one through eight. Zoom level 8 is most zoomed in, and zoom level 1 is most zoomed out. Each level zooms by a power of two. In other words, at zoom level six, each region is twice the width it was at zoom level five.
 
== Accessing map images directly ==
 
The Second Life map images are stored on [http://aws.amazon.com/s3/ Amazon Simple Storage Service (Amazon S3)].  You can access the map images directly on the Amazon S3 servers using the following URL format:
 
<nowiki>http://map.secondlife.com/map-{z}-{x}-{y}-objects.jpg</nowiki>
 
Where:
* <tt>z</tt> - zoom level from 1 (most zoomed-in, where each tile is one region) to 8 (most zoomed out). Note this is ''backward'' from how are addressed when making Leaflet API calls in your JavaScript.
* <tt>x</tt> & <tt>y</tt> - the X and Y coordinates on the Second Life Grid of the region. For example, region Ahern is (997, 1002).
 
Even zoomed-in tiles are addressed by their region coordinates. That is, tiles with zoom greater than 1 are stored by the <tt>x</tt> & <tt>y</tt> of the regions at their lower left corners. You can find the zoom tile containing region (X,Y) for zoom level Z with the filename map-Z-X'-Y'-objects.jpg where:
 
X' = X - (X % (2<sup>Z - 1</sup>) )
 
and
 
Y' = Y - (Y % (2<sup>Z - 1</sup>) )
 
Note that 2<sup>Z - 1</sup> is the number of regions encompassed by the width of a tile at resolution Z.
 
=== Examples ===
 
For example, at Z = 1, four region tiles are:
 
* http://map.secondlife.com/map-1-1000-1000-objects.jpg
* http://map.secondlife.com/map-1-1001-1000-objects.jpg
* http://map.secondlife.com/map-1-1000-1001-objects.jpg
* http://map.secondlife.com/map-1-1001-1001-objects.jpg
 
These four region tiles are compressed into the single tile:
 
http://map.secondlife.com/map-2-1000-1000-objects.jpg
 
The following shows the map zoomed all the way out, showing the once-entire Second Life world view:
http://map.secondlife.com/map-8-1024-896-objects.jpg
 
The following displays a single tile contained in the view above, zoomed all the way in:
http://map.secondlife.com/map-1-1027-1019-objects.jpg
 
=== Implementation notes ===
 
The map generation process is more scalable than the previous release, and is able to image the entire Second Life grid of about 30,000 regions in less than two days. 
 
There is a "decay period" for offline regions. If a region is disabled, the tile will stay up for several days (in case it comes back or something else has gone wrong) before the tile disappears. That several-day period will be longer than the time it takes to update existing regions or put new regions on the map.
 
=== Getting a map URL from LSL ===
 
The following LSL script illustrates how to display a map of the current region to an avatar:
 
<source lang="lsl2">
ShowMap(key avatar) {
    string url = "http://map.secondlife.com/";
    vector sim_coord = llGetRegionCorner();
    string x = (string)((integer)(sim_coord.x / 256.0));
    string y = (string)((integer)(sim_coord.y / 256.0));
    url += "map-1-" + x + "-" + y + "-objects.jpg";
    llLoadURL(avatar, "View the sim map", url);
}
</source>
 
== Release notes ==
 
This section describes new features and known issues with the current release of the Map API.
 
Version 2 of the Map API was released on Dec 12, 2016.
 
* Converted the Map API to Leaflet.
 
Version 1 of the Map API was released on Jan 15, 2009.
 
* See also [http://blog.secondlife.com/2009/01/22/improvements-to-mapping-and-upgrade-to-slurlcom/ Philip Linden's blog post announcement].

Latest revision as of 11:14, 13 December 2016

NOTE: This is an official Second Life API provided and documented by Linden Lab. Its use is subject to the API Terms of Use.

Getting Started

The Second Life Map API is a JavaScript library to embed Second Life maps onto your web pages. It's a purely client-side JavaScript API. If needed, you can also directly access the map images.

NOTE: This API is still in beta. URLs and API signatures may change. See the Release Notes for information on new features and known issues.

Map UI features

The Map API enables you to create web pages that have web map functionality, using maps of Second Life, rather than Earth. In general, the default map interface looks as shown here.

Map ui cropped.png

The main map display area shows the current map area. By default, the map provides the following features:

  • Click and drag the mouse pointer to pan the map around.
  • Double-click to zoom in by one level (power of two).
  • Click anywhere on the map to open a "teleport" popup (see Teleport popup below).
  • Use the mouse wheel to zoom in and out. See Zoom levels for more information about zoom levels.
  • Use the zoom controls at upper left to zoom the view in and out.


Teleport popup

Teleport window.png

Clicking anywhere on the map opens a popup (left) where you click. Click "Visit this location" to start the Second Life Viewer & teleport you where you clicked. This feature is implemented with the gotoSLURL() global function.


Working examples

See Map API Basic Examples for a detailed explanation of the working examples at http://maps.secondlife.com/examples/.

Using web links

The web site uses the Map API to provide a mechanism to teleport directly to locations in Second Life from web pages.

For more information, see Using Second Life URLs (SLurls).

Include the API files

To use the Map API, put the following lines at the beginning of each HTML page. This includes the JavaScript & CSS so that you can create the map & display it correctly.

<!DOCTYPE html>
<html><head>
    <meta charset="utf-8">

    <script src="http://maps.secondlife.com/_scripts/sl.mapapi2.js"></script>
    <link rel="stylesheet" type="text/css" href="http://maps.secondlife.com/_styles/sl.mapapi2.css">

    ...

All the examples also require additional script statements in the HTML header.

Stylesheet

You can also include your own stylesheet to style the other elements of your page. For example:

    <link rel="stylesheet" type="text/css" href="http://maps.secondlife.com/_styles/sl.mapapi2.css">
    <link rel="stylesheet" type="text/css" href="myStyleSheet.css">

Browser compatibility

The Map API has been tested to work with the following browsers:

  • Internet Explorer 6.0
  • Internet Explorer 7.0
  • Firefox 2.0 or greater
  • Safari 2.0

Other browsers may work but little issues may appear. Unless otherwise noted, all features work in all supported browsers.

Comments and feedback

If you encounter problems or bugs or have feature requests, please email webmap@secondlife.com.

Happy coding from the Second Life Web team!

Basic concepts

The Map API is built around the Leaflet web map library. Leaflet provides many options, methods & events for customizing the presentation of your Second Life map.

About coordinates

Map coordinates are based on the Second Life grid system for positioning regions.

Webmap coords.jpg

As illustrated in the diagram above, the Map API maps the Second Life world to the upper right quadrant of an earth map. A large scaling value equal to 220 or 1,048,576 defines the largest region coordinate at the top and far right edge of the displayed area. This value creates a map area with room for one trillion sims.

The little blue square illustrates where the populated sims are in Second Life.

Zoom levels

There are eight zoom levels: one through eight. Zoom level 8 is most zoomed in, and zoom level 1 is most zoomed out. Each level zooms by a power of two. In other words, at zoom level six, each region is twice the width it was at zoom level five.

Accessing map images directly

The Second Life map images are stored on Amazon Simple Storage Service (Amazon S3). You can access the map images directly on the Amazon S3 servers using the following URL format:

http://map.secondlife.com/map-{z}-{x}-{y}-objects.jpg

Where:

  • z - zoom level from 1 (most zoomed-in, where each tile is one region) to 8 (most zoomed out). Note this is backward from how are addressed when making Leaflet API calls in your JavaScript.
  • x & y - the X and Y coordinates on the Second Life Grid of the region. For example, region Ahern is (997, 1002).

Even zoomed-in tiles are addressed by their region coordinates. That is, tiles with zoom greater than 1 are stored by the x & y of the regions at their lower left corners. You can find the zoom tile containing region (X,Y) for zoom level Z with the filename map-Z-X'-Y'-objects.jpg where:

X' = X - (X % (2Z - 1) )

and

Y' = Y - (Y % (2Z - 1) )

Note that 2Z - 1 is the number of regions encompassed by the width of a tile at resolution Z.

Examples

For example, at Z = 1, four region tiles are:

These four region tiles are compressed into the single tile:

http://map.secondlife.com/map-2-1000-1000-objects.jpg

The following shows the map zoomed all the way out, showing the once-entire Second Life world view: http://map.secondlife.com/map-8-1024-896-objects.jpg

The following displays a single tile contained in the view above, zoomed all the way in: http://map.secondlife.com/map-1-1027-1019-objects.jpg

Implementation notes

The map generation process is more scalable than the previous release, and is able to image the entire Second Life grid of about 30,000 regions in less than two days.

There is a "decay period" for offline regions. If a region is disabled, the tile will stay up for several days (in case it comes back or something else has gone wrong) before the tile disappears. That several-day period will be longer than the time it takes to update existing regions or put new regions on the map.

Getting a map URL from LSL

The following LSL script illustrates how to display a map of the current region to an avatar:

ShowMap(key avatar) {
    string url = "http://map.secondlife.com/";
    vector sim_coord = llGetRegionCorner();
    string x = (string)((integer)(sim_coord.x / 256.0));
    string y = (string)((integer)(sim_coord.y / 256.0));
    url += "map-1-" + x + "-" + y + "-objects.jpg";
    llLoadURL(avatar, "View the sim map", url);
}

Release notes

This section describes new features and known issues with the current release of the Map API.

Version 2 of the Map API was released on Dec 12, 2016.

  • Converted the Map API to Leaflet.

Version 1 of the Map API was released on Jan 15, 2009.