I’m happy to announce that GeoMeta for ACF is now available in the WordPress plugin directory.

GeoMeta for ACF is a very easy way for editors and admins to add spatial data to posts, pages, taxonomies, users or anything else that Advanced Custom Fields supports.

Simply add a GeoMeta field to your Field Group, then draw the geometry you want to use for that post. You can use the usual ACF settings so that a GeoMeta field only shows up on certain post types or other conditions.

 

All data stored with GeoMeta for ACF can be queried with spatial queries since it uses WP-GeoMeta-Lib under the hood.

Store campground locations and then search for the campground that’s closest to a given city. Find out which precinct a user lives in. Mark all the locations you blog from and then show them on a map.

There’s a ton you can do with spatial data once you’ve captured it. GeoMeta for ACF is so easy that anyone can use it.

Go Download It Today!

Yesterday was GIS Day, according to Esri, which makes today PostGIS day! To celebrate the two special days it seemed  appropriate to release a new version of WP-GeoMeta. The main new feature of WP-GeoMeta version 0.2.2 is support for separate latitude and longitude meta fields.

When plugin developers want to implement location information they tend to implement it with separate latitude and longitude fields. If they do any spatial searching it’s using trigonometry functions and custom queries.

WordPress itself supports method of storing spatial points, it’s the WordPress Geodata standard, with key names geo_latitude and geo_longitude.

Starting with version 0.2.2 WP-GeoMeta supports the WordPress Geodata standard out of the box, and additional key name pairs can be added as simply as calling:

    // WP_GeoMeta::add_latlng_field( <latitude field name>, <longitude field name>, <spatial meta_key name> );
    WP_GeoMeta::add_latlng_field( 'myplugin_lat', 'myplugin_lng', 'myplugin_geo' );

A few new hooks were added in this release as well. Documentation for WP_GeoMeta::add_latlng_field and the new hooks can be found on on GitHub.

As always, WP-GeoMeta can be downloaded from the WordPress Plugin Directory or from GitHub.

As part of writing a demo of WP-GeoMeta I needed to be able to buffer points by X meters, while the points were stored as Lat,Long coordinates. It’s been a while since I dusted off the trigonometry, but luckily Movable-Type.co.uk had several examples of the math I’d need in JavaScript which I was able to adapt to MySQL stored functions.

The result is MySQL Stored Geo Functions, a small collection of MySQL stored function definitions for working with Lat,Long coordinates.

Currently there are three available operations:

• Buffering a point (by meters or miles)
• Calculating distance between two points (the Haversine function)
• Creating a line given a point, bearing and distance (in meters or miles)

Screenshot

Here’s a sample buffering result. The point in red has been buffered by 30 miles, producing a polygon with 8 points.

The generated polygon is also used in a query with a WHERE ST_INTERSECTS(polygon, point_geom) since MySQL doesn’t have ST_DWITHIN. The Marker is the result of the query.

 

 

Contributions Welcome

If you’ve got MySQL spatial functions that you’d like to share, please submit a pull request! I’ll also continue to add any useful new functions I write.