Terrier is our visual weather toolkit, built to integrate with leading map frameworks and to display time-series weather data interactively. Our new weather integration brings Terrier’s advanced weather visualization capabilities to MapLibre Native, giving iOS developers another powerful option for building high-performance weather applications. 

MapLibre Native

MapLibre Native is the mobile version of the MapLibre toolkit. It’s used in a variety of map-based apps for your phone. It’s free to use and has an active development community, of which we are a member. So it’s funny that we’re just getting around to supporting it.

On the web, MapLibreJS is one of our most popular Terrier integrations. That hasn’t been the case on mobile devices until recently.

Now we do have mobile users. In fact, some big ones, like Carrot Weather, use Terrier on its own. Other customers, like Element, use Mapbox. Expanding our MapLibre weather integration gives developers even more flexibility when choosing the mapping technology that best fits their application.

MapLibre on iOS supports the Metal rendering toolkit, as we do, so tight integration has always been possible. Now we’ve finally gotten to it, and it looks great!

Building a MapLibre Weather Integration

If you’re writing a MapLibre app, the integration isn’t terribly difficult. Once the style is loaded, you create a custom layer and insert it where you want it to go, like this.

With a vector map toolkit like MapLibre, we can draw the weather underneath the labels or wherever else you might like. The results are quite pleasing, allowing weather data to fit naturally into the overall map experience without sacrificing performance.

This MapLibre Native weather integration also gives developers precise control over where and how weather layers are rendered, making it easy to display forecasts, radar, wind, and other visualizations exactly where they’re needed.

MapLibre Weather Integration Behind the Scenes

This is likely to interest only a few, but we’ll throw it out here. We had to make some changes to MapLibre.

Terrier’s rendering pipeline is fairly complex. We draw all sorts of things to all sorts of places. That might be temperature or wind with particles. It’s all very fast, but complicated.

MapLibre’s existing callbacks for Metal layers had the rendering pipeline set up in a predefined way. Terrier needed to do a bunch of work before that happened.

To facilitate this, we added another callback before the map is drawn, allowing Terrier to do its work there. Then we used the regular callback to do the final render to the screen.

The beauty of open source is we’ve contributed that change back, and it’ll appear in the next week or so.

Using the Terrier MapLibre Native iOS Integration

If you’re a Wet Dog Weather customer, you’re free to use Terrier in all of its forms with your data.

For this integration, we provide a TerrierMobile repository that includes both the Mapbox and, now, the MapLibre examples. Reach out to us for a link.

Whether you’re building a new weather application or expanding an existing one, our MapLibre weather integration makes it easy to combine MapLibre Native with Terrier’s high-performance weather rendering. We’re excited to contribute improvements back to the open source community while giving developers another flexible way to build fast, interactive weather experiences on iOS.