Part 2: Future 3D Support in WhirlyGlobe-Maply

Last time we looked at WhirlyGlobe-Maply's existing 3D support.  It's considerable, but often hard to use.

FlyQ EFB and NATS Airspace Explorer

Now we'll talk about where we're heading.  It's all about the data sources.

Putting the 3D's in Data

Most of our users have fairly limited data processing capabilities.  Say you want to add elevation to an app.  We'd say:

• Gather all the elevation data you need.  USGS is a good source.
• Stitch it all into a single giant image in Spherical Mercator
• Chop that image up into tiles using this random tool we have on github
• Load the resulting sqlite file onto the device.

Easy enough, right?

Yeah, not so much.  That's why you see so few WG-Maply apps with elevation.

It's not just us, you know.  OpenStreetMap data is much easier to use when you move from Planet Files to Metro Extracts and Vector Tiles.

Structured 3D Data Sources

What developers really want is web services that they can plug into their apps.  Also pizza that lifts itself into your mouth.  Pizza robot.  Patent pending.

People want to point their app at an elevation, 3D building, or vector tile service and stuff just happens.  So let's look at some of those services and the formats they support.

Two New Styles of Elevation

Elevation tiles are an obvious thing.  We already support Cesium's elevation, but there are others out there now.

Mapzen came out with a straight up elevation tile service a few months ago.  There are a few minor technical hurdles, but it could be made to work well with the toolkit.

Mapzen Elevation Example

Mapbox came out with their own elevation tile service shortly thereafter.  It's a different approach, with similar problems in 3D but could also be made to work.

Courtesy Mapbox terrain-rgb post

So there you go.  We'd like to support Mapzen & Mapbox elevation data for 3D.

Buildings with Height

OpenStreetMap buildings have height (usually, mostly).  Mapbox has been showing this off lately in their APIs and Mapzen has been doing it for a while in Tangram.

Mapbox Data w/ Mapbox GL

We'd like to support height in vector tile data.  Not too difficult, obviously, but cool.

Now for the harder stuff.  Let's start with a detour into data formats.

GL Transmission Format (glTF)

The 3D file format we support right now, Wavefront OBJ, is old and weird.  We need to move to something new and... less weird.

glTF is backed by the Khronos  Group with lots of work from the Cesium folks.  It's a new, relatively simple optimized model transmission format.  Easy to read, fast to transmit, it solves a lot of problems for models like these.

And it enables some even crazier stuff.

3D Tiles

The Cesium folks have a 3D Tiles proposal out that looks great.  It's open, they've got example implementations, and they're trying to make it an OGC standard.

3D Tile data displayed with CesiumJS

That approach is well suited for mobile.  We can't display as much as a desktop can, but we can display a lot.

Naturally, we'd love to support this in WhirlyGlobe-Maply.

Point Clouds

We already support point cloud display for things like LIDAR.  It's restricted to a Sqlite based format read on the device.  Hey, it's what the customer needed at the time.

San Simeon LIDAR

We'd love to extend this to services like Greyhound, an open source streaming data server.  We'd also like to add support for the GeoPackage point cloud extension.

Summary

There's a ton of explicit 3D support in WhirlyGlobe-Maply for interaction, model construction, and motion.  We'll continue to push in these areas and others we haven't talked about, like 3D weather.  But that stuff is driven by high end client needs.

NATS Airspace Explorer

What we'd really like to do is support these newer services for our regular users.  If you have other services you'd like to see or, better yet, some budget, please let us know.

Android Tutorials

We have tutorials!  For Android!  Yay!

Screen shot of a web page?  I'm not proud.

A big thanks to Nicholas for putting these together.  And to José for doing the binary AAR examples.

Getting Set Up

The first few tutorials focus on setting up a really basic project and getting the WhirlyGlobe-Maply library included.  We now have three ways of doing this from least Android-y to most Android-y.

• Build from source
• Download a nightly build
• Include the AAR from JCenter

Yes, we're doing nightly builds for Android and we have the JCenter/Maven thing set up.  Once you've got the toolkit included, you can peruse the tutorials on actually doing stuff.

Enough With the Typing

There's nothing more to say.  Go check out the tutorials if you're doing Android development with WhirlyGlobe-Maply.

If you'd like more tutorials on iOS or Android, open up an Issue.  That's how we communicate.

We can thank the Support Customers for this since it came out of their budget.  More support contracts means a bigger budget.  It's all spent on stuff like this.

Mapzen Vector Tile Service

We're going to support Mapzen's Vector Tile Service.  Currently that means we read their vector tiles.  In the future we'll support their style sheets.

Courtesy Mapzen

Let's do a little background and then get to the details.

Vector What Now?

We've been slinging around vectors for years in WhirlyGlobe-Maply so vector tiles weren't a huge diversion.  We even had our own format for a while.

These days vector tiles means Mapbox Vector Tile format, but it implies two other things:

• A curated version of OpenStreetMap suitable for web and mobile map display
• One or more style sheets to describe the visual representation

You might call this a Vector Tile Service if you were so inclined.  Developers want to shove a map underneath the thing their app is actually doing.

It's a trivial, seamless process with an image tile service.  We're going to make it just as easy for a vector tile service.

Here is our roadmap to get there.

Mapzen Vector Tile Service

We can parse and display Mapzen's vector tiles just fine in either GeoJSON or Mapbox Vector Tile format.  But we use really simple style sheets.

Must be night or something

That looks kind of meh.  For a real map we need better.  There are a number of ways to do style sheets, but I'd like something that requires minimal upkeep.

Mapzen has a Javascript/C++/Java based renderer called Tangram.  It's got it's own style sheet format.  That format is.... very specific to Tangram. 

I've been on the fence about their style format.  Some discussion was in order.

Data Formats & Common Usage

Data formats have crazy parts.  Go look at PDF (better yet, don't).  You have to decide what's common usage and what parts you ignore, at least for a while.

The Mapzen folks were kind enough to host a meeting where we could explore this.  It looks like the common usage among their various style sheets is blunting the weirdness.  They've got professional cartographers using it, in addition to engineers, which is a big plus.

In short, when we see some deep_Tangram_weirdness we can substitute minor_WG-Maply_weirdness and it'll look pretty similar.  Good enough. 

There's Open and Then There's Open

The most attractive thing about the Mapzen Vector Tile Service is the terms of service.  You can use the data in any API and in a variety of ways.  As long as you're not completely rude.

Best of all, you can mix online and offline databases without violating the license.  That makes it perfect to slip into a WhirlyGlobe-Maply app and in our test apps.

That's not a knock on other services.  I get that the API and data are often tightly linked by a license.  That's how you make money.  And speaking of money...

Roadmap and Funding

The vector tile part works just fine in WhirlyGlobe-Maply now.  We still need to implement the Tangram style format.  We're just wrapping up Styled Layer Descriptor support so it shouldn't be all that difficult.

It does require money.

That's the roadmap.  If you're interested in any part of it, speak up.  I get asked about this a lot, so it'll get paid for eventually.

Android Support Contract

The Android version of WhirlyGlobe-Maply is coming along really well.  So well that we're ready to introduce a support contract.

Support is a tricky proposition.  Like any product, we're betting we'll bring in more than it costs to make.  In this case, that means the cost of fixing bugs.

How Does Support Work?

It's pretty basic.  You ask questions and we answer them.  You find bugs and we fix them.  Oh and you pay money.  That's important.

We've had the iOS support program going for more than a year now and I like it!  It's helped move a number of projects forward.  Users feel free to ask deep questions, get stuck less, and we get a sense of what's hard and what's not.  Oh, and we spend some of that money on boring features.

You can communicate with us via Slack or Github Issues or just email directly if you're being all stealthy.

Shut Up and Take My Money

Android support for WhirlyGlobe-Maply is $1200 (USD) per year.  For comparison, iOS support is $850.  Yeah, Android is more money.  We're totally 100% behind the Android version, but it is just more work.

I've been secretly selling the Android Support Contract for months now and it's going well.  Get yours while the offer lasts!  [It'll last a long time.]

Integration with Micello Indoor Maps

A few months ago we were approached by Micello about displaying their indoor maps in WhirlyGlobe-Maply.  They provide indoor maps to a ton of interesting companies.

Taste the Capitalism!

Seemed like an excellent idea so we went ahead and whipped up a tutorial and demo.

Micello Tutorial

Micello was kind enough to provide a few examples.  We chose the Westfield Valley Fair mall near Cupertino.  I used to live there and have a certain fondness for it.  There was also a recent story about the minimum wage change that cut right through the mall which we incorporated into the display.

If you've got a Micello account feel free to work through the tutorial and let us know if you have nay questions.

On To the Future!

Ranen put together a rather nice example app, which is what you build in the tutorial.  It shows off some fairly clever display with styles, selection and a few other things.  But we could do more for optimization, label layout, and general display flexibility.

Our example was built on the globe, but you could as easily put it on a regular map.  Doing something special for pure indoor map display is also an interesting idea, though this seems to work well enough.

WhirlyGlobe-Maply is an open source toolkit, so you can take the code and run with it.  Feel free!  But we do consulting if you've got a budget and some requirements.

Map Features in WhirlyGlobe-Maply

I'm going to discuss map related features of the WhirlyGlobe-Maply toolkit. The SDK is an open source, mobile centric geospatial display toolkit. It’s used in a variety of weather, aviation, geography and map apps.

Two of the more prominent examples are Dark Sky, a weather app and National Geographic World Atlas, which is exactly what it sounds like.

NatGeo World Atlas & Dark Sky

The globe apps are best known, but WhirlyGlobe-Maply has huge support for traditional 2D map apps too.  We're going to talk about some of those features, but let's start with map apps in general and one in particular.

Map Apps

Mapping is one of the more popular categories in the app stores. Both Apple and Google have their own map offerings and toolkits, but they're poor if you have your own data? That’s where toolkits like WhirlyGlobe-Maply come in and we’ve built a number of features specifically for those sorts of apps.

One of the more capable map apps that uses the toolkit is Gaia GPS.

Fact: 30% of hiking app screenshots are Yosemite.

Gaia GPS displays a variety of image and vector based data sources. It’s popular among the backpacking and off roading communities.  It can work without a network and is very careful with battery.

Let’s move on to one of the key features for nearly every map app: Image Tiles.

Image Tiles

A basic feature required for map display is loading and rendering of image tiles. We’ve moved well beyond Web Map Service on mobile devices and we now expect tiles. This might be a Web Map Tile Service (WMTS), but is more likely to be a fixed quad tree of tiles like that coming from Google Maps or OpenStreetMap.

Efficient image tile loading is a tricky problem. Mobile devices have network constraints and we want to make careful use of data caching. WG-Maply can handle this for both globe and map, but there’s an interesting variant for the map case.

In the example we’re loading three levels of tiles based on the current window. We start with an extremely low resolution, then overlay that with slightly higher resolution and finally toss in the proper resolution. It gives the user something to look at while the system loads the good stuff.

Tricks like these are important to efficient map display on mobile, but let’s take a quick detour through some really basic functionality.

Vectors, Labels and Markers

Any credible map toolkit should be able to display some basic features and WhirlyGlobe-Maply is no exception. These include vectors for areal and linear features, labels for points and of course markers.

All very simple to us.  Vectors, for example can be consumed from a variety of data sources, like GeoJSON or (ESRI Shapefile). Labels and markers are 2D features and can interact through an adaptive layout engine.  All of them provide selection feedback too.

It’s what the developers do with these features that gets interesting. That leads us to a complex modern feature: vector tiles.

Vector Tiles

Mapbox has popularized vector tiles with their OpenStreetMap data set. Theirs is a Google Protobuf based format, which is as complex as it sounds. The fundamental ideas are simpler.

Vector tiles are to image tiles as vectors are to images. They are just chopped up geometry representing what’s in each map tile. You can use them much more flexibly than images.

A very custom example of vector tiles.

Believe it or not, National Geographic World Atlas uses vector tiles hosted by Mapbox.  The rest of it is completely custom.  And, okay, it's technically a globe.  But if National Geographic doesn’t have some cartographic street cred, nothing does.

A more normal use of vector tiles.

The Gaia GPS developers use vector tiles they generate themselves to draw contour lines. The data is styled using Mapnik XML which is associated with the Mapnik map renderer.  Gaia GPS also has a street layer based on the same approach.

WhirlyGlobe-Maply has vector tile support down solid, but style support is still in flux and likely to be for a while. We can support older style formats like Mapnik XML and developers can always go off on their own. Newer formats like Mapbox GL Style Sheets are not fully supported yet. We also hope to add in Styled Layer Descriptor since it's an actual standard.

Vector Tiles are a bit trippy so let’s go back to some more basic map features.

Wide Vectors

Widened vectors are one of those obvious things that require some work to implement.  OpenGL ES has a basic line implementation, but it looks kind of... meh.  If you want lines that have smooth edges and neat little joins, you need something more.

WhirlyGlobe-Maply's implementation involves a custom OpenGL ES shader and a bit of math.  Line intersections are calculated on the fly (sort of) and width can be varied as needed.  Typically this just looks like constant width lines as the user moves in and out.

Look deep into my shader

Oh, and you can do dashed lines and other effects.  Wide vectors work both on the flat map and the globe, but they're primarily a map feature, just like the next one: clustering.

Marker Clustering

Clustering markers is a pretty simple idea. When you have a lot of markers on your map, it can look bad. Best to gather them up into groups and display the groups.

Simple enough, but our maps move so we have to do something more. As the user zooms in, the groups come apart and as zoom move out, the groups form. It’s tricky to implement, but looks quite nice.

In truth, clustering can be used on both the globe and the map even it’s nominally a map feature. Let’s look at something purely from the 2D map.

Infinite Scrolling

For certain types of map projections, the extreme west and east extents represent the same point (really, line). This means the user expects to move the map and have it wrap around.

Bonus question: What about wrapping top to bottom?

Infinite scrolling is simple in concept, but tricky to implement. The rendering isn’t bad, but when you add in feature selection and overlaid data it gets interesting. You know what else is interesting? Map projections.

Map Projections

The real test of a map toolkit is whether it handles explicit map projections. Actually, that’s not true. Plenty of map toolkits only work in a simple map projection, known as web mercator. But if you want to hold your head high in a room full of cartographers, you should have map projection support.

Does this projection make my poles look big?

Web mercator, shown here, is the most common projection in use on mobile. It has its problems, particularly near the poles. We can thank Google Maps’ dominance for this affront to cartography.  There's data in plenty of other projections and good reason to use them.

From left to right we’ve got:

• A data source in British National Grid overlaid on a web mercator map.
• The same data source overlaid on a British National Grid map. The web mercator data source is being reprojected.
• The same thing on a globe. Because it looks cool.

Though the vast majority of our users will always use web mercator, WhirlyGlobe-Maply can do more. It uses the Proj.4 coordinate system package internally and can handle a variety of useful map projections.

Conclusion

Map toolkits for mobile devices are hot right now. There are a number of excellent ones, though most are tied to specific data services like Apple or Google or are proprietary or both.  A few are open source, like WhirlyGlobe-Maply.

We’ve discussed some basic features and a few advanced ones we consider essential for map display on mobile. If you’re looking to build an app, we hope you’ll look beyond the proprietary services to something like WhirlyGlobe-Maply.

Special thanks to Stamen for the Stamen Watercolor map tiles, derived from OpenStreetMap data, used in many of these examples.

Map Projections

Let's talk map features.  How about custom projections?

Does this projection make my poles look big?

Spherical Mercator (web mercator) is the most common map projection you'll see.  It's a fairly simple unraveling of the earth, but its main purpose is to annoy cartographers.  Did you know the EPSG code for Web Mercator stands for "DIAF".  True fact.  Look it up.

Our users mostly stick with web mercator, but we now let you specify your own custom projection.

Proj.4 CoordinateSystem

Like all the cool kids we use Proj.4 to represent coordinate systems.  In theory this allowed us to use a wide variety of systems.  In practice, we just used Spherical Mercator, Plate Carree and a very weak geocentric.

Recently we exposed Proj.4 directly with a MaplyProj4CoordSystem.  It's simple enough, if you're familiar with Proj.4.  Here's an example for British National Grid.

Full disclosure, there's actually a datum grid shift that goes with that for proper BNG.  We've shortened it for the example.

You can get these Proj.4 strings from spatialreference.org, among other places.  But odds are if you have the need, you already have the string.

British National Grid

The folks at Ordnance Survey were kind enough to help us sort this out.  Let's look specifically at the British National Grid, starting with a data source in BNG.

BNG tile source on spherical mercator

That's a 2D map with a base layer in web mercator (Stamen Watercolor) overlaid with a dummy tile source in BNG.  As far as these things go, that's the easy case.  Let's look at a more difficult one where the map itself in BNG.

BNG tile source on BNG map

In this one the map is in BNG with a base layer in web mercator and an overlaid dummy tile source in BNG.

That's pretty cool!  Web mercator stretches far outside the boundaries of the BNG system, so we convert the tiles to BNG and toss out any that don't overlap.  And it works!  But there's more.

BNG tile source on globe

Okay, not all that difficult as these things go but it looks cool.  We're just overlaying a dummy BNG source on the globe.

You can find all of these examples in the AutoTester app for iOS.  And there's more...

Android

This is something I hope to say a lot more in the future:  Custom map projections are also available on Android in the develop_3_0 branch!

A triptych of British National Grid

You can find these examples in the AutoTester app for Android.  I'll explain AutoTester in more detail soon, but it's already been a great help in development.

Next Up

The hard part here was tracking down the weird corner cases and systems which just don't play well with each other.  There are likely to be a few more like that, so let me know what you find.

We've got more map features in the queue, including some vector data display.  Stay tuned!

CartoType GL

In cooperation with CartoType Ltd, I am proud to announce CartoType GL for iOS and Android.

Parks are green!

CartoType GL is the next generation of the CartoType map toolkit.  It's got all the flexibility of the existing library for map representation, routing and address searching, but we've add a zippy OpenGL ES renderer.

What is CartoType?

CartoType is an offline map library that works with limited resources.  This makes it popular on smartphones and other situations where the user is not connected to a network.  It can handle a variety of data inputs, making it easy to use your own data, but can also deal with the usual OpenStreetMap cases.

I wonder where this is?

The existing CartoType library does a really nice job representing complicated maps in a very small space.  It's primarily a static map rendering library, so when you use it on a smartphone it'll render the map when you stop moving.  What we've done is upgrade the renderer.

What is CartoType GL?

CartoType was already doing a fine job representing maps.  What it needed was to draw them faster.  CartoType GL is just what it sounds like, an OpenGL ES based version of CartoType that solves the speed problem.

CartoType GL marshals the resources of the existing library to convert data to internal vector tiles.  Those are are processed into OpenGL ES compatible data and rendered at a nice zippy, interactive speed.  Basically just what you'd expect in a modern map toolkit.

Online vs. Offline

There are some excellent cloud based map solutions out there for map representation, routing, address searching and so forth.  CartoType GL is not that; it's an offline solution.

I have no idea where this is.

Why offline?  Well, it's actually a different problem.  You can cobble together offline solutions from the online technology, but they're not great.  They're too big, they don't do routing well and they're focused on display.  If you want to do a good offline map toolkit it's a different beast.  That's what CartoType is.

Cost & Availability

CartoType GL is, logically enough, being sold through the CartoType company.  They are the ultimate source of details on this effort.  Contact them for a license.

We hope to get the iOS version out in April.  Android should follow shortly after that.

Boring Technical Details

WhirlyGlobe-Maply is the open source toolkit we (mousebird consulting inc) make and it has two levels.  The core is a C++ rendering and object management engine.  Above that is an Objective-C interface on iOS and a Java interface on Android.

CartoType GL uses the core C++ renderer directly.  Rather than expose high level WG-Maply functionality, we interface with the GL renderer.  This makes CartoType GL a much simpler map centered toolkit.

WhirlyGlobe-Maply is and will continue to be open source.  This arrangement is just like one of the commercial apps that we work on.  It's even contributing functionality back, making the toolkit better for everyone.

Marker Clustering

Let's continue with the new map features and look at a really cool one paid for by Miizee.

The number one response to marker clustering has been "I thought you already did that."  So I guess we were on the right track.

What is Clustering?

It's easier to show than tell, but I'll belabor the point.  Clustering is when you take a bunch of markers that would normally overlap and turn them into a single grouped marker.  It's meant to make your map more readable.

Clustering works both on the map and the globe.  It's easy to access and to modify.

Cluster Specifics

If you're already making MaplyScreenMarker objects and letting the layout engine handle them, then it's easy to cluster.  Just add the attribute kMaplyClusterGroup and set it to 0.

Already know I'm going to be tired of orange

Cluster Group 0 is set up by default and will make orange clusters with a number in the center.  Since clustering is a function of the layout engine it'll fire off on a regular schedule and clusters will interact with other markers and labels.

Let's look at a simple example.

That sets up a few markers, then asks the system to cluster using the default cluster group.

Selection works too.  If the user taps on a cluster group, you get all the individual markers back.  They're tagged as part of a group too.

Rolling Your Own

We've set up the default clustering mechanism with an instance of MaplyBasicClusterGenerator.  You can set one of those up yourself and add it to the MaplyBaseViewController.  You can even overwrite the kMaplyClusterGroup for 0 and change the defaults.

The MaplyBasicClusterGenerator gives you access to a variety of attributes, such as:

• The image used for a cluster background.
• The animation time for markers joining and leaving a cluster
• The shader to use for movement.

If that's not enough control, you can just subclass MaplyClusterGenerator and control it all.  When asked, you'll return a UIImage and the size of the marker you're creating.  The system will handle the rest, including texture atlases, animation and cleanup.

Behind The Scenes

There's obviously some cool stuff going on here.  Not only are clusters very flexible, they're fast.

Clustering is hilarious around the edges

Several versions ago we started using OpenGL ES shaders for the markers and labels.  This let us draw a lot of them, but also start treating them as normal geometry.  Animation and clustering are two of the more interesting results.

Wrapup and Commercial Plug

Enjoy the most popular feature you thought WhirlyGlobe-Maply already had!  Hopefully it's cooler than you already thought it was.  Let us know what other features we obviously do but may not have implemented yet.

Thanks again to Miizee who paid for this development.

Coming up, more map features!

Infinite Scrolling

It's been way too long since my last post. And that means I've been busy. So many things to do. So many new features.  So much Android.

Stamen Watercolor + NAIP Ortho

But let's talk maps.

The Map, It is Flat

WhirlyGlobe-Maply isn't just about the globe.  There's that second part, the "Maply" bit.  That's a flat map.  It can also be a 3D map, but no one cares, they just use the globe for that.

Lots of users do use it as a flat map, though.  Sometimes (<cough> most times </cough>) that's the best way to present geospatial information.  And most of WhirlyGlobe-Maply's favorite tricks work in 2D.  Some are exclusively 2D.

Like infinite panning.

To Pan and Pan and Pan and Pan

Sometimes you need a 2D map of the whole world.  Sometimes you need to pan past the edge of the world and keep going.  Because that's how the world is.  Or would be if you stretched it out.  Or your map is near the date line.  That happens.

The nausea means it's working

This feature is baked into the MaplyViewController.  It's the viewWrap property and it's on by default.

The implementation is harder than it looks, particularly for annotations and selection.  So bask in our glory.  Or buy a support contract.  Maybe both.

Up Next

The globe gets all the press and the pretty pictures.  So we'll talk about some more map related features, like vector tiles and marker clustering.

And soon, WhirlyGlobe-Maply 2.4.  It's basically done, I just need kick it out the door.

WhirlyGlobe-Maply 2.4 Beta #8

The latest beta (#8) of 2.4 is available.

You have no chance to survive make your time.

You can get this one of three ways.

• The binary release can be gotten there.
• Cocoapods can be had directly from this URL or with the tag v2.4_beta8
• You can just use the repo with the tag v2.4_beta8

That's just the framework.  I'll put together the test app and its data when the release is ready.

"Did I miss betas number 1 through 7?" you may be thinking.  Yeah, pretty much.  I made them for clients, but haven't been aggressively pushing them on users.

What's New In Beta #8

Well, it's all new to 2.4, so go check out the announcement post.

I am repeating myself, yes.

The pretty stuff is pretty, but the stability of 2.4 is really profound.  We've been integrating with a number of high traffic apps and have cleared up a lot of edge, corner, and middle cases.  This is a great release.

How Many More Betas

Probably just the one more beta.  Things are nicely stable and I've got a pretty short list of bugs I want to fix.  

After that, it's WhirlyGlobe-Maply 2.4.1 which... okay I'm already working on.

WhirlyGlobe-Maply 2.4 Features

There's a lot of cool stuff in WhirlyGlobe-Maply 2.4.  It's been about a year since 2.3, so there'd better be.

Stamen Watercolor + atmosphere = Wha?

Let's start with the popular stuff, move on to the pretty stuff and then round it up with everything else.

Basemaps

Remotely pageable image basemaps are the single most used feature in the toolkit.  Version 2.4 introduces a new way to specify them.  Rather than use the base URL and let the toolkit figure out how to add the level, x and y you can just tell it.

Give the MaplyRemoteTile source a URL with {x}, {y} and {z} in it.  We'll just replace the level {z} and the location {x} and {y} with the tile ID as required.  This means you can shove whatever other junk you need into that URL, like your access token.  Take a look at this tutorial for an example.

Cocoapods

The Podspec is back, at least in beta form.  You can find a WhirlyGlobe.podspec in the develop branch and, in combination with a tag (v2.4_beta8) you can use it right now.  I'll update the official one when we release.

Atmosphere & Night/Day Shading

You'd think I'd have done atmosphere long ago.  You'd be wrong, it's not all that useful.  But it sure looks cool!  And, okay, hardware is a lot faster now.

It does look cool, I'll admit.

There's a new shader for when you're zoomed out and one for the ground itself.  I can add the shader you need when you're zoomed way in looking toward the horizon if necessary.  And by necessary, I mean I accept cash and checks.

The night/day shading requires two sets of image basemaps.  You can see the ones I'm using the ComponentTester app.  Just turn on the "Stars and Sun" and "Night/Day Images - Remote".  Which brings us to....

Stars, Sun & Moon

That's right, you can show the sun, moon, and stars in their (maybe) correct positions.  I'm reasonably certain about the sun, less so about the moon and not so much on the stars.  It sure does look cool, though.

We're all going to die!

You might want to supply your own sun texture if mine doesn't amuse you.  It amuses me.  Consult the Component Tester app for the details.

Some of these features are cheap to run, some aren't.  For full atmosphere, you'll want some decent hardware for the fragment shaders.  Please don't overuse them.  I know you'll overuse them.

Particle Systems

We've got particle systems now!  They look awesome!  I have no examples I can show you!  Because client!

This is one of those advanced features, I'm afraid.  Drawing them is easy enough, but feeding them is work.  We're planning a nice example for the next version.

Elevation

This is another one of those cool features that people love, but rarely have money to pay for.  Well, someone finally did, so here you go.

It's just very gray right there.  Desert or something.

Specifically, this is support for Cesium's mesh terrain format.  You can get that from them and I like how it's structured.

At this point we just have elevation.  Cesium structures its terrain in a different tiling system from everything else, so we can't overlay images.  Future version, I think.

3D Models

The toolkit has support for true 3D models now, particularly Wavefront OBJ, a file format old enough to vote.  Obviously something newer would be nice.  Again, send your requests in the form of cash or check.

In addition to the model support, we can now do proper OpenGL ES based instancing.  This means you can have a bunch of these things moving around without using up all your memory.  And they can move, but more on that later.

There's also support for raw geometry.  If you can't specify your geometry through one of the standard ways, you can just start throwing triangles at the toolkit.  Obviously an advanced feature.

Shapes

3D shapes are like models, but much simpler.  This version added extruded shapes, which is nice for things like arrows.

Shading.  Is a thing that could use work.

You can control the location and orientation of shapes more precisely now too, with direct access to the matrix.  Shapes can, in some cases, be converted to models.  That's useful if you have a lot of them and want to make use of the model instancing optimizations.

Motion

Used to be you had to remove and add the same object repeatedly to make it move.  That's fine for one or two objects, but what about 2000?

Screen markers & labels in 2D and models and shapes in 3D all have Motion variants that take end points and durations.  In combination with the new fade and enable times, you can do some tricky, tricky things.

If you're moving one or two objects, don't bother with this.  If you're moving a few thousand, it's useful.  The motion is shader based, making it very efficient.

Animation State & Viewpoint Control

Controlling where the user is looking at has been annoying in the toolkit, particularly when heading and tilt are involved.  Now you can control it very precisely, even animate it.

Take a look at the WhirlyGlobeViewControllerAnimationState in the WhirlyGlobeViewController.  There are methods for getting and setting that state, as well as animating and interpolating between states.  There's even a delegate for doing your own animations.

Mapbox Vector Tiles

There's been a lot of work on Mapbox Vector Tiles, but it's advanced stuff.  I'll write up a user's guide to their vector tiles with WhirlyGlobe-Maply... one of these days.  You can use them, with a lot of caveats.

Courtesy National Geographic.

As a transport mechanism, the toolkit can handle some pretty interesting stuff, like vectors and images.  We're doing that with National Geographic World Atlas.

Styles are more complex.  Right now you can specify a style sheet with Mapnik XML, which is a little hard to work with.  Mapbox GL Style sheets are partially implemented, but that format is in flux right now.

It's very much for advanced users at the moment.  I'd like to change that in the future.

Performance & Twiddly Stuff

There are a bunch of features which, while important, are very boring if you're not writing a big, complicated app.  Course, those are my customers, so let's dive in.

Texture atlases have been in there for a while, but now they're exposed at the high level.  Take a look at the addTexture:desc:mode: method in the WhirlyGlobeBaseViewController.  That's a rather flexible way to add textures standalone or to the atlas and replaces all the other addTexture methods.  And texture atlases are very, very fast.

Billboards have been in there for a while, but can now be specified with a MaplyScreenObject. With that, you control the layout and use text that taps directly into the glyph engine.  Fast & memory efficient.  Expect to see more use of MaplyScreenObjects in the future.

Getting close to the ground has always been a problem, but it should be no more.  There were a variety of centering and offset fixes for a variety of visible features.

Selection supports absolutely everything now, from moving labels to polytopes to 3D model instances.  Not a lot of fun to write, but important.

Most objects now support vertex attributes.  You can send these along for the ride through the system and then read them in your own custom MaplyShaders.  For the handful of you that write custom shaders, use it for passing in things like height and then shading based on elevation.

Widened vectors have been in there a while, but they're not heavily used outside of vector tiled maps.  There are some improvements and bug fixes that should help.

Screen based texture application is now available.  That makes texture application for an areal feature look logical in the 2D display.

Absolutely everything is thread safe (probably).  My high end users make heavy, heavy use of dispatch queues so you can hit the toolkit from just about anywhere now.  If you're chasing performance, do your adding and removal in a dispatch queue, or several.  The toolkit can handle it and it works well on anything newer than an iPhone4.

Crashes & Bug Fixes

Version 2.4 includes a veritable metric ton of fixes for layer teardown, view controller teardown, dispatch queue teardown (or lack thereof) and all sorts of other weird corner cases.  Thanks to everyone who gave me access to their Crashlytics accounts!  Yes, I know it's called Fabric now, but that's a dumb name.

One bug a lot of you had seen is the BigDrawable crash.  Turns out that was related to running low on memory, but was not caused by running out of memory.  Despite my attempts to deny it, it was real and it's now fixed.

Conclusion

That's about it for 2.4.  It's a huge release and it's taken far too long for me to get it out.  Let's see if we can do better next year, eh?

And the best way to make that happen is to buy a Support Contract!  If I get a few more signups, I'll start doing nightly builds and try out monthly releases.