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Alami: Hello, everybody, and welcome
to "Secrets and Surprises of the Google Geo APIs".
My name is Ossama Alami. I'm a developer advocate
on our Geo Developer Relations team,
and I'm here today presenting with Aaron Jacobs,
who is a software engineer on the Maps API team.
So what do I mean when I say
"Secrets and Surprises of the Google Geo APIs"?
Well, what I want to do--
what we want to do in today's session is give you,
firstly, an overview of your options as a developer
when you think about Geo, Spatial,
and Geospatial APIs at Google,
and then go into some specific features of the Maps API,
the Earth API, Fusion Tables, our web services,
and the Static Maps API, to highlight some features
that you may not know about, some features
that you may have seen but don't know how to use,
and give you an idea of what's new,
and some exciting features.
So we'll start with the overview.
When you think of Geo at Google, people typically think of
the Maps API Version 3, or the Maps API,
and it is our primary mapping API,
and what you typically think of when you think of Maps at Google
as a developer.
But we have more than just these,
what I'll call user-facing APIs, these mapping APIs.
There's the Earth API, which we'll talk about today.
This lets you embed Google Earth and a web page
There's a Maps API for Flash,
for any action script developers in the audience.
We have a Static Maps API, which we'll also talk about today.
And then for Android and IOS devices,
we have a native SDK, that you can use for mapping
if you're building a native application.
But there's more than just these user-facing APIs.
There's a suite of developer tools,
supporting APIs within Geospatial at Google,
that support you as a developer in building these applications.
There's our web services, Fusion Tables,
both of which we'll talk about, KML, which is an open standard
for representing geospatial data,
SketchUp, which is a tool for 3D modeling,
and you can then take those models
and put it on Google Earth,
and then Earth and Earth Pro themselves,
which are client applications that you can use
to visualize your data
as well as work with certain data formats.
But there's more to it.
Google has over 100 different APIs and developer products,
and lots of them that you may not immediately think of
actually have a notion of place,
a notion of location or some geospatial aspect to them.
You can get a user's location using the Latitude API,
geotag imagery using Panoramio and Picasa,
or geotag videos with YouTube API,
updates using the Buzz API,
and then there's some developer tools,
if you are an organization or a developer
that has lots of geospatial data, you know,
satellite images yourself, you can use Earth Builder
and Earth Enterprise to work with and visualize that data,
and then tools like Refine and BigQuery,
that don't necessarily have a specific geospatial application,
sorry, a specific geospatial feature--
but they are tools that you can use to work
with geospatial data sets, and then query them,
or refine that.
So that's sort of a very quick, broad overview
of what is available to you as a developer
when you think of Geospatial at Google.
And we'll go right now into some really exciting features
of Maps API Version 3--
again, some features you may not know about
and some features that are brand-new.
First, I'll start with an overview of the Maps API.
We released Maps API Version 3 at last year's I/O, out of labs.
Now if you're-- and we deprecated Version 2.
Now if you have an active Version 2 site,
I don't want you to worry.
We have a 3-year deprecation policy.
But I hope some of the things you see today encourages you
to switch to Version 3,
because that's where our active development is,
and that's where all of our new features are built upon.
The advantage of Version 3 is also that it was built
from the ground up to be both a desktop
and a mobile web-mapping API.
So in addition to support and the mobile browsers
for Android and Safari, we also support Blackberry 6 devices,
and the Samsung Bada browser,
and then the standard desktop browser support as well.
You'll notice IE 6 isn't listed here.
While we--while the maps-- thank you.
While the Maps API will work in IE 6 and will not break,
there are certain features that will--
they'll degrade well, but they won't be available to IE 6.
But you can rest assured that your map will continue to work
and function with Internet Explorer 6.
I said "loads of features". Here are just some of them.
The things in blue are some of the things
that we're going to talk about today.
As you can see, there's more to it than just a map and markers.
You can do so much more with the Maps API.
And the first thing I want to talk about
is 45-degree imagery.
So this 45-degree imagery, you'll notice
I'm looking at an angle, an oblique angle.
If I zoom out-- this, by the way,
is Google's headquarters in Mountain View, California,
which is about 40 miles south of us here--
if I zoom out, I have the standard satellite imagery.
Now, I have the smooth transition as a user
when I zoom in to switch to a 45-degree imagery,
and right now I'm looking north, which we'll call 40--
which we'll call, sorry, zero degrees.
I can look east at 90 degrees, 180, 270, and back to zero.
And this is really high-resolution imagery,
so you can see as I zoom in, you get a lot--
a lot of detail, more than what you would get
with just satellite maps.
And as a user, I can turn off 45-degree imagery,
or go back and add labels.
We have an ever-increasing list of cities
that's available worldwide.
So I was gonna show you Santa Cruz,
which is just further south of us here,
and we also have Venice, Italy,
as well as a large, ever-increasing amount of cities
And so what's the code look like
to enable this 45-degree imagery?
It's not enabled by default for the Maps API,
but it's really, really simple, and this will be a common theme
in this presentation.
The code to enable these features
is actually really, really simple, really easy.
Only a couple lines of code, and you can have a world
of new possibilities and features in the Maps API.
So I simply set the map to-- set, on the map,
call "set tilt," pass in "45" for 45 degrees,
and this enables 45-degree imagery,
so when a user zooms in at an appropriate zoom level,
it'll naturally switch to that 45-degree imagery.
And then to reset it,
if I want to disable satellite imagery,
I just call "map.set tilt to 0."
And if I want to programmatically
set the heading,
I just call "map.set heading," and pass in one of those--
one of those degrees.
Another feature that is unrelated to 45-degree imagery,
but I do like to demo with 45-degree imagery,
because it really gives you an idea of the surrounding area,
is this overview map control.
So this, I can move the box either in here,
or as I pan, the overview map control will update,
and if I go back to map, it'll switch to map.
This gives me a higher perspective,
a zoomed out perspective of where I am looking at,
so the user can really understand the location,
and this will collapse or expand.
So the code to this is, again, very, very simple.
When I create a map, I pass in "map options."
If I want the overview map control,
I just pass in "overview map control true,"
and if I want it open by default,
I pass in an overview map control option,
and I say "opened equals true."
A new feature in the Maps API which I really like
is marker animations.
We have two animations that we support.
You can see those markers dropping.
There's the drop animation, and there's--
as I move this marker, we have draggable markers as well.
You can see the marker drops and animates.
This makes it a little bit more of an interactive experience
for the user, feel like they're actually performing an action,
and confirmation that it worked,
because they see the animation.
And then we also have the ability
to make all the markers bounce.
I really urge you to use this feature with caution,
because a little bit is fun.
Too much is a little annoying.
We'll leave those bouncing.
When I create a marker, if I want to pass in an animation,
or if I want to animate it, during creation of the marker,
I just pass in the animation option here
and I set the animation that I want.
In this case, "drop."
The other animation we support is "bounce."
If I've already created a marker and I want to set an animation,
I just call marker--
on the marker I call "set animation"
and I pass in the animation that I want.
And then if I want to clear the animation,
just call "set null"-- sorry, "set animation,"
"pass," and "null."
So there's been lots and lots of improvements to markers
in Version 3 of the Maps API very recently,
including many speed improvements.
If you want to learn more about this stuff,
you should go to the session entitled "Speedy Maps"
which is 10:45 A.M. tomorrow.
Layers is another feature of the Maps API
that you may not know about.
This enables you to very easily add additional data
on top of the map.
We support various types of layers.
The first UM I'm going to demo-- Geo RSS--
let's you consume a Geo RSS file or a service
and then easily display that on the map.
In this case, we're hitting the Flickr API
to get geotagged imagery of our tech writer's dog
across North America.
And then the other way that you can get your data
on top of it, on top of the map very easily
is to use KML.
And in this example,
I'm just loading KML for transit lines in Chicago.
So the other examples here are more using Google's data
and showing that on top of the map.
In this case, I'm showing traffic in Chicago.
Every time I practice this,
this highway has always been red,
so I don't know what's going on there.
And then, bicycling-- this changes the view of the map
and then highlights bicycling routes,
roads that are known to be good for biking,
and roads with bike paths.
You can see, as a bicyclist, I can get a really good idea
of what's easy to bike through in Chicago.
And then, Panoramio--
I talked about Panoramio briefly earlier.
Panoramio is an image-hosting site
that has exclusively geotagged imagery,
and we've added a Panoramio layer,
and it's more than just pulling in imagery.
You can see here, I get a good idea
of user-contributed images of Chicago,
but I can also filter by either a specific user--
so if you have a Panoramio account
and only want to show your photos on the map,
that's very easy to do-- or I can filter by a tag.
So here I'll search for Wrigley, and you see,
the stadium shows up here and there are various images
that I can pull up.
And then down south,
there's actually a Wrigley Building in Chicago as well,
and that's coming up.
So all these layers work pretty similarly.
It's very easy to instantiate them
for both KML and RSS.
I use the google.maps KML layer.
It understands both formats,
and I pass in the path to that file or that service
that's returning either KML or Geo RSS.
Traffic layer and bike layer and Panoramio layer,
I just instantiate it.
And then, for the Panoramio layer,
if I want to filter by user or by tag,
I just call "Panoramio layer.set tag"
or ".set user ID" to filter by those.
And then in all cases, to add it to the map,
I just call the set map property of the layer,
and I pass in the map that I want it to appear on.
If I want to remove it from the map,
I just call "set map, null." I talked briefly about KML.
If you want to learn how to create highly performant KML
for both consumption in the Google Maps API
and Google Earth, you should go to the session
titled "High Performance KML for Maps and Earth"
which is this afternoon at 3:45.
Draggable directions is one of my favorite features.
It was a highly requested feature for the Maps API,
because people saw this on maps.google.com.
They saw that they could drag directions,
and now whenever they see directions,
they want to drag it, right?
The user sometimes knows a better path
to get to a location.
Here, I'm mapping from Moscone to our headquarters
in Mountain View, and you know, maybe I know that 101
is really terrible this time of day,
and I'd rather take 280.
I can very quickly click and drag that over,
and it'll update the textual directions
on the right automatically.
Another feature that you may not know about is
these text directions actually link up directly to the map,
so as I click, a user can see that individual turn.
Draggable directions, again very easy to add to a map.
This example shows you how to add directions to a map.
The things I want to highlight are the top,
these renderer options.
I'm setting draggable to true, and I'm passing this
into a directions renderer.
Directions renderer is the object
that manages rendering the directions,
both in textual format and on top of the map.
Now, since the user has an ability to drag directions,
you as a developer may want to know
when they've interacted with that
and when the directions have changed.
You just need to listen to directions changed event,
which we now expose.
And then you can perform some action.
Street View is another very, very popular feature.
We have a huge Street View coverage around the globe,
and when we implemented Version 3 of the Maps API,
we wanted to implement it in such a way
that it was usable on all mobile devices.
So we can't rely on Flash being installed, for example.
So Street View in V3 of the Maps API
and this gives us the ability to support you as the developer
adding overlays on top of the Street View,
so markers and info windows,
as well as completely custom Street View,
which is a really exciting feature that I'll demo.
And then, we've also exposed the Street View service,
the data service, which lets you query us
to find out where Street View imagery is available
and some other data about that Street View imagery.
Here's an example of overlays.
In this case, these overlays are just markers.
I have just a cafe, and a bank,
and here I'm programmatically going to switch to Street View
using this button.
And you can see, the marker shows up here,
and so does the info window on top of the Street View.
Meanwhile, I'm panning, and everything updates.
As I move down the street,
you can see there's another marker here
that gets larger as I get closer.
Naturally, it's a Starbucks.
And that works fine as well.
So this gives you more options when you're working
with Street View in displaying data on top of it.
Another feature I'm going to demo is custom Street View.
Here we have Street View imagery--
our Google Street View imagery-- outside of our Sydney office.
There's a bunch of buses parked in front
because it's across the street from a casino.
As I move down the street, you can see this is
the standard Street View imagery.
If I move up the street, I've added a link,
for this demo, to the Google Sydney office.
This is not part of our Street View imagery
that we provide to you,
but something that you can do as a developer.
And here, I've taken a panoramic image of the interior
of the Sydney office, the lobby, and I can view this,
and then, again, link back out into the street.
It's a great way to do indoor mapping,
and so that the imagery for Street View doesn't end
on the street, but rather takes you into a building.
If you want to learn how to do this, you should go to
the "Map Your Business Inside and Out" session,
which is at 1:45 P.M. tomorrow.
So I said V3, we optimized it for mobile.
We are also very concerned about keeping speed up
and latency down.
So when we wanted to add features to the Maps API,
has to download and then the browser has to parse,
but we wanted to add some new and exciting features
and keep the load time down.
So we've introduced this concept called libraries.
And using a library is very simple.
When you load the Maps API, there's just a script tag
to load the Maps API.
I specify a libraries parameter.
I pass in a comma-separated list of libraries.
In this example, you see Panoramio,
which I demoed earlier, is actually a library
that I loaded for that demo.
And here I have Geometry, AdSense and Places,
which I'll demo right now.
Geometry is a library that lets you compute angles,
distances, and areas from latitudes and longitudes.
So if you want to do some spherical geometry queries,
you can use it-- load this library and use it.
And it also comes with an encoding library
that lets you encode a path,
so encode an array of latitudes and longitudes
into a string representation of that,
as well as decode that back into latitudes and longitudes.
I imagine most of you are familiar with AdSense, yeah?
AdSense is a way for you, as a developer or a publisher,
to monetize your site by placing relevant ads on your site,
and then there's a revenue-sharing model.
What we found was that a lot of web pages have just a map,
or a map is the core component of it.
That's what the user is interacting with.
And AdSense only displays relevant ads
based on the context, the textual content of your website.
So it wasn't getting the relevancy
of where the user was looking at to display relevant ads.
Well, we fixed that with the AdSense library
for the Maps API Version 3.
This is a library that you can use to monetize, now,
your mapping application.
And it takes what the user is looking at
and serves relevant ads for that.
So if a user is looking in wine country,
north of us in San Francisco, they'll likely see ads
about hotels, or winery tours, or things like that.
So it becomes much more relevant ads
that a user is likely to click on.
It's very easy to add this to your map as well.
All you do is create arbitrary div for the Ad Sense ad
to live in, pass in the format of the ad,
which is a standard AdSense format,
and then if you want the ad to live on top of the map,
you can pass in a control position for the ad,
but the ad can also live off the map
and still be tied to the context of the map--
your publisher ID, so we know where to send the checks,
the map that it's tied to,
and then whether it's visible by default.
And then I just create the ad unit "new google.maps.adsense,"
add unit, pass in the div that it's living on,
and the ad unit options that I just described.
And this is what it looks like.
This is an example of an ad showing up on top of the map.
Here you can see, I'm looking in Monterey,
which is south of us, another tourist destination,
has a famous golf course nearby, so I'm seeing ads for hotels
and a golf course.
So you can see, I'm moving.
This moves to the bottom left.
Let's see if this works.
Sorry about this, guys. This moves to the right.
Apparently if I use a drop-down box three times,
it'll fix itself.
So very, very easy to-- so that sort of shows you
where it can live on the map and then the format will change,
the actual format of the ad--
I'm not going to click on that right now--
to either--any of the standard AdSense formats.
So you know, one of them is a long bar,
one of them is a bigger box,
one of them is a smaller box, et cetera.
And then Places-- Places we announced
that we launched out of developer preview
in the session earlier today.
There's also a Places library that you can load
for the Maps API Version 3.
It supports two services: auto-complete,
which, if you're familiar with maps.google.com,
when you start typing, you see a list of possible results,
auto-completion of addresses
or auto-completion of business locations.
We're giving you the ability to have that same feature
on your sites,
using the auto-complete functionality and Places.
And then we have a Places search service,
which given a bounting box or a latitude and longitude
and a radius,
will let you search for local business listings
and points of interest.
If you want to learn more about how to use Places,
including the web services we're launching with Places,
you should go to the "Location-Based Development
Using Google APIs" session,
3:00 P.M. tomorrow.
And so I talked about libraries,
but what we also make available are utility libraries.
These aren't loaded through the libraries tag in the Maps API,
but are instead open-source utilities that you can download,
modify, and then use in conjunction with your map.
They are developed by the Maps API team,
and we do actively develop them and support them.
You'll find utilities that do clustering,
that do custom markers and info windows,
that do root boxing, and then a very highly requested feature,
Google Earth integration,
we recently released as an open source library.
So you can download this library
and get the Earth button on Maps.
You know, it's Map, Satellites, Earth,
and it'll transfer all the items that you have on your map
to the Earth instance and sync the two.
So a user can now view the map-- view your content
using Earth as well--
which leads me into discussion about the Earth API.
Again, the Earth API is a way for you to embed Earth
so that you can define the user experience
and what content is displayed on top of it.
It does require a browser plug-in, the Earth plug-in,
which has support on both Windows and Mac.
And what does this look like?
There we go. So here's Google Earth.
I can turn on borders.
There are various options for what I can do.
I programmatically set a button
that just jumps to San Francisco.
I can pan down here and turn on or off terrain.
One of my favorite features is the buildings layer.
This gives you a really good idea
of what a city looks like in 3D
as opposed to a top-down view of a map.
And as this loads,
you'll see more and more detail will come in,
in San Francisco and the Bay Bridge.
And then, we recently added trees to Google Earth.
We have over 80 million trees mapped.
We get this data from a variety of sources.
A lot of it is actually from satellite imagery now,
so it's where we pick up trees
and add the specific type of tree to that location.
Here we have trees, and if you don't believe me,
we have also enabled Street View.
If I click and drag this here,
there are all the trees.
Another thing I'll show you in Street View--
we'll jump to Moscone here--
is, as opposed to Street View
on Google Maps and the Maps API,
Street View in Earth is actually continuous.
It does interpolation of the imagery, between panoramas,
and so it's a much more fluid experience
going up and down the streets.
So that's a very cool feature, only available in Google Earth.
I must say though, my favorite feature in Google Earth
is historical imagery.
This gives you access to Google's historical imagery,
Google is a relatively young company.
We've been around for about a decade,
and Keyhole, the company that was acquired,
that then built Google Earth, is even younger than that,
but we've been actively acquiring historical imagery
and adding it to Google Earth,
which you can access through the API.
This enables you to build really new types of applications
that deal with history and the context of a place.
Here I'll show you.
I'll enable historical imagery.
I've got a slider-- which as a developer,
you can show or not show.
And then, I can disable it, re-enable it,
and I'll jump to San Francisco in 1988
to show you a cool demo that I like to show.
So there was an earthquake in San Francisco in 1989
that collapsed this freeway here
that led sort of through the heart of the city.
I'll show you. This is the city.
So we can actually see that.
This is prior to the earthquake,
and if I move the historical imagery forward to 1993,
you can see that the earthquake--
or, sorry, the highway collapsed,
and then they took down the freeway.
But there's still a freeway here, and as I move forward,
you can see that they actually tore down that entire freeway
and built this ground-level promenade.
And then, jumping to the current time,
you can see that they've added trees
and it actually looks quite pretty.
But what I love to show about this demo
is that, even 20 years later, there is a scar
that runs through the city.
Where the freeway used to be is now all parking lots.
In fact, this is the only new building that's been developed,
and if I jump back to 2008,
you can see it's a parking lot as well.
So 20 years later, after the earthquake,
there is still a visible scar that you can see
through the city, that you can now--
you can tell these stories
using our historical imagery in the Earth API.
And then I want to talk about Fusion Tables.
Fusion Tables is basically a tool for storing,
collaborating, and sharing large amounts of data.
You can think of it as a cloud-based database,
with tight integration with the Maps API,
spatial query support,
and a sequel-like query syntax and API.
The best way to show you Fusion Tables
is to actually do a quick demo.
So here I have Fusion Tables.
I have a list of tables that I own,
and I'm going to show you two examples.
First is this table of roughly 2,000 Brazilian beaches.
I have the name of the beach, latitude, and longitude.
One of the most difficult-- one of the most common questions
I get is, you know, "I have 10,000 points
"that I want to show on the map.
What's an easy way to do this?"
Well, creating an individual marker for those points
gets quite cumbersome and very slow,
can be very slow in a browser.
So Fusion Tables supports a very easy way
to visualize this data.
I can just click "visualize map," and you see,
it's rendered out all these 2,000 markers
on top of 256-pixel square tiles,
which is the same tiling scheme that the Maps API uses,
so it's a transparent tile with just the markers,
to determine where a marker is and then pull that data through.
So this is a very quick map.
There is no lag.
I very quickly added these 2,000 points.
And then if I want to display a heat map,
I just click a check box.
Now, it's very easy to display a heat map.
A heat map is, in case you don't know,
not a map of temperature.
It is a map of density.
So there is a high density of beaches located down here,
and it's not quite as dense with beaches over here.
And then the other demo I'll show you is this.
So I downloaded a CSV from the American Community Survey,
which is this government organization
that puts out demographic data every year.
So it's broken down by congressional districts,
and it has some demographic data,
like what's the median age of this congressional district.
And then, using Fusion Tables, I merged this CSV.
I uploaded the CSV to a fusion table,
and then I merged that fusion table
with a fusion table of all the U.S. Congressional districts,
the shapes of the U.S. congressional districts,
which I found on Fusion Tables.
We have a set of public tables that you can download from,
and you can make your data public as well.
So you can see, you know, here is a shape of--
or various shapes of the first Alaskan Congressional district.
Maybe there's only one.
There's only one.
And I can visualize this on a map,
so it supports more than just points.
It supports polylines and polygons.
This is not a particularly interesting map, because,
you know, I can click on this and I get all the data,
but it doesn't really tell me anything.
I can very quickly click on configure styles.
Let's say I want to color this map
based on the median age of the population--
let's say from green to red
And you see now I get a thematic map,
a map that I can very quickly look at
and see which Congressional districts trend older
and which Congressional districts trend younger.
And then if you're done, if this is all you want to show,
I can actually just get an embeddable link here,
copy and paste into my web page, and I get a map.
But there's more.
I mentioned tight integration with Fusion Tables
in the Maps API Version 3.
Well, that's exposed through another layer
called the Fusion Tables layer.
You can see this is a Maps API site,
not an embedded I-frame from Fusion Tables.
It is in fact styled,
which is a feature Aaron will talk about in a little bit,
and here I'm displaying the Brazilian beaches
on top of my Maps API site,
so I can just define the experience however I want.
And I can enable heat map through the Maps API.
Maybe I need to click this two more times.
Yay, that worked.
And so I'm also going to show you
the Congressional districts maps that I just made.
And it supports arbitrary queries, so here,
I'm selecting the shape of the congressional district
from my table ID, where the median age
of the total population is over 30,
but I can very quickly switch this to 40,
and very quickly I get dynamic results back,
so you can build really
lots of exciting applications this way.
There we go.
Fusion Tables layer works like the other layers.
You just create a new Fusion Tables layer.
In this case, I pass in a query.
If all I want to show is my fusion table
without refining or filtering the query at all,
I can just provide the table ID.
Otherwise, the sequel-like syntax,
where you can say average age is above 40, and then
if I want it to be a heat map or not,
I just set heat map to true or false.
If I want to set it, it's the same as other layers.
Just call "set map," or call "set map," "pass,"
and "null" to clear it.
So that's just a tiny bit of the features of Fusion Tables.
If you want to learn more about Fusion Tables,
how it integrates with the Maps API,
and some new features we're launching,
you should go to the "Managing and Visualizing
Your Geospatial Data with Fusion Tables" session,
which is today at 1:15.
With that, I'll bring up Aaron.
There you go.
Jacobs: Thanks, Ossama.
Is this on? Yes.
Thanks, Ossama. And, hi, everybody.
I'm here to talk about Maps API web services
and the Static Maps API.
What is the Maps API web service?
Well, in contrast to the user-facing APIs
Static Maps API and so on-- this is a database service
for you to call from your native code or backend server
and to consume information in JSON or XML.
It lets you benefit from Google's expertise
in geospatial data, so you can do geocoding to find out
where a street address is on Earth,
in latitude/longitude, and other information about it.
You can do directions queries and more,
which I'm going to talk about here.
I do remember that we have a terms of service
that requires you to eventually do something with this data
Flash, Static Maps API, Earth API, so the idea here
is you can do further computation with your server
or your application and eventually display a map
to a user doing something intelligent
based on the results of that computation.
Oh, also, I should mention, most of the services
I'm going to talk about here are also available
for that to see that you can also use it from the client
if that's appropriate for your app.
So the first one I'm going to talk about
that you may have missed is the Elevation API.
Now this is exactly what it sounds like.
It allows you to give us a line or a set of points
and to find out the elevation of those points on earth.
That's both elevation above sea level
and below sea level for points that are underwater
in oceans and lakes.
This uses our cool bathymetry data that we have
that you can see on Google Earth, previously.
Now you could use this to visualize elevation profiles
or do intelligent things for bikers or walkers
and other stuff that I haven't thought of.
You guys are the creative ones.
It's really easy to use.
For example, here I have sort of a trivial request that says,
"Given a path from lat. long. 0-0 to 0-10--"
this is from the Atlantic Ocean to the shore of Africa--
"sample this path three times."
You could use a much larger number.
This is for my example.
"And tell me the elevations of the points along that path."
So you get back a JSON or XML response
that looks something like this.
You see we sampled it at 3.00010 and one in the middle,
and you can see that you go from approximately
5 kilometers under the ocean to a little bit shallower,
to about sea level as you hit the coast of Africa.
It's that easy to use.
Check out the documentation.
It has a couple other clever features,
like you can specify points as addresses
if that's helpful for you.
Another service I'd like to talk about
that we launched last week is called the Distance Matrix API.
This is where you have a set of origins and destinations,
and you want to find out for each pair of origin/destination
how far they are from each other.
Now, this is in terms of drive time and drive distance
or walk time and walk distance, not as the crow flies,
so this can be pretty useful to you.
It uses our Directions API data.
So for example, if you want to find out how far it is
from L.A. to San Diego and--
sorry, from L.A. or San Diego to San Francisco or Sacramento,
you would make a request that looks like this--
you see it's very easy-- and get back this information.
Now what's this good for? You could, for example,
use this to make an advance store finder app,
which given a set of your stores or locations
or whatever it is that you are displaying,
and the user's location, or a couple of users' locations,
home and work,
you can do intelligent things based on this,
much smarter than getting the closest store as the crow flies,
which might involve a heavily trafficked road
or something like that.
Another directions related service is route optimization.
Now, if you've used the Directions API,
you know that you can give an origin and a destination.
Say the user wants to go from A to D, via B and C,
so that means you need to hit points B and C in the middle.
Previously, if you tell us this, we'll just naively follow
the set of points that you specify,
but this may not be optimum.
What we allow you to do is, in your way point list,
you can say "optimize true," and what we'll do is
we'll reorder those intermediate way points for you
so that the user, or whoever's traveling,
has the most efficient route through all these points.
This is known as the traveling salesman problem,
for those who are familiar from computer science.
As with all of the things I've mentioned so far,
it's very easy to use. You just say "optimize, true."
We hold the origin and destination fixed
because we assume that's where the user wants to start
and wind up, and we do the magic for you.
We'll give back the right directions
based on the optimum order, and if your application
needs to know how they were reordered for some reason,
we return the field called "way point order"
that tells you that.
So for example, with this query here,
I've generated a few maps using aesthetic Maps API--
or one map actually-- so this is from L.A. to New York
via these intermediate cities.
The red path is what you'll get if you do it in the naive order,
and you can see that it crisscrosses
all over the country.
It's very inefficient and probably takes a few days.
Whereas the green path, you see it's been reordered
to do this in an efficient way.
So yeah, it's exactly what it sounds like.
Another directions-related feature
is bicycling directions.
So previously in the Directions API,
we only supported driving and walking,
and you guys are probably familiar with these
which allows you to get directions, as you know.
We've added support for bicycling directions,
and all you do is say "mode equals bicycling,"
and we'll use what we know about bike paths and local roads
and that sort of thing to find routes
that are suitable for biking.
So for example,
here's a trip from--sorry,
from Santa Monica to Hollywood in L.A.,
and if you're familiar with L.A., you see this red path,
which is the driving path-- takes a couple of freeways
that you really don't want to take on a bike.
But the green path takes bike paths and local roads,
and it's probably quite a bit more pleasant.
We also of course adjust all of the drive--sorry, ride times
and that sort of thing according to biking speed.
Moving on, another announcement that we're making--
or have made recently, excuse me--
is that now everybody is allowed to use SSL for our web services
If you're not familiar with SSL, this is a way
to encrypt the data that the browser
or your code sends to Google so that nobody in between
can snoop on it.
You can use this if you have sensitive user application data
that you don't want anybody in the middle to see.
And it's just kind of a good idea for the Internet,
for users' data.
Previously this was a feature that was only available
to Maps API Premier customers, but now you can all use it.
Everybody can use it.
It's very easy.
All you do is make sure you're sending your request
to maps.googleapis.com, and change your URLs
to use HTTPs, and it's that simple.
You don't need to make any other changes.