For those of you not familiar, Cesium is an open source JS library for creating 3D globes and 2D maps. The library is published under the Apache 2.

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3 For those of you not familiar, Cesium is an open source JS library for creating 3D globes and 2D maps. The library is published under the Apache 2.0 license, and it runs in your favorite modern browser on your favorite computer, smart phone, tablet, phablet, or really any device that has WebGL support. Last year I saw a Cesium globe running on a Samsung smart fridge. Cesium was also chosen as the NGA map of the world web client 3

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5 What is 3D mapping? I m sure many of you already have some sort of idea for what it means to have a 3D map. It s data with a height, right? 5

6 For example, this is technically a 3D map. And so is this. These are using height to represent some sort of metadata like population. And while these are 3D maps, this is probably the most narrow view of the possibilities that are out there with 3D mapping. 6

7 This is more what I m talking about when I say 3D Mapping. This is a fully interactive, high-resolution 3D recreation of Center City in Philadelphia, rendered in real time with Cesium and 3D tiles. This is reality model created by Bentley Systems using the photogrammetry software called ContextCapture to stitch together about 28,000 photos to created a textured 3D mesh. 7

8 Here s another example of a 3D application. This one was developed by NASA to visualize the two- and three-dimensional precipitation data collected via satellite. The radar technology collects 3D scans of snow and water above the Earth s surface, and since this data is collected in 3D, it only makes sense to visualize it in 3D. 8

9 Here is an example for a virtual 3D city. This is a geoportal application created by Switzerland in part of an open data effort. The application was designed to visualize and share data collected by the Swiss government, and is used by roughly 50,000 users a day. 9

10 And finally, Doarama showcases another great use case for 3D mapping: as an interactive replay of 3D time-dynamic data. In this case, this is showing GPX data collected by a participant in the Tor des Géants, a 6 day 205 mile (330im) endurance race though the Aosta Valley in Italy. An application like this can help athletes analyze strong and weak parts of the event to improve for next time. It is also a great way to share the experience with friends and family. 10

11 Now that we understand a little bit about what we can do with 3D mapping, let s take a look at some of the advantages of using 3D. One of the biggest drawbacks of 2D is that we live in a 3D world, so some semantic value is lost when it is projected into a 2D view. Let s first look at a few exaggerated examples that demonstrate the value that 3D visualization adds. 11

12 In this example, we have a few different airspaces and we want to determine whether the airplane is in the restricted airspace shown in red. From this view it looks like it s possible that the plane is in both the green and the red airspace. However, we really don t have enough information to make a conclusion. Let s take a look at this same scene in a 3D view 12

13 Surprise! The plane is actually in neither airspace. To figure this out in 2D, we would have needed some kind of legend to tell us the altitude of the plane, and the lower and upper altitudes of the airspaces. In 3D, we can just look at it. 13

14 Here is another similar example where we have a volume that represents radar coverage. Again, in 2D it looks like the aircraft might be inside the range, but we can see in 3D that this is not the case. This is where we get the term flying under the radar 14

15 In this example, we want to determine if there is line-of-sight between the radar ground station and an aircraft, here represented by the yellow point. In both 2D and 2.5D (which is a 2D map with height) it looks like the line from the ground station to the aircraft is unobstructed, but if we switch to 3D 15

16 It turns out the curvature of the earth is really important sometimes. The surface drops about 8 inches per mile, which is definitely significant. And as we can see from this view, the line-of-sight between the two positions actually goes under the surface of the globe, so we can therefore conclude that the ground station cannot see the aircraft. I know these are fairly simplified examples, but they help demonstrate some of the ways 2D maps can lie to us. Let s take a look at a few more practical examples to see the kind of impact that 3D visualization can have. 16

17 I really enjoy hiking, and some time in the next few years I would love to visit Yosemite national park and see the half dome rock formation. To get an idea of what I can expect when I get there, I wanted to take a look at a map of the terrain so prepare for the hike. These are two examples of traditional topographic maps. The map of the left has contour lines at certain intervals, so we can start to see that maybe where the lines are closer together that the terrain is more steep, and we have a legend so we can read what the elevation is at a certain place. Another common method for looking at the topography is to see the hillshading. We can start to see that this looks like a valley with rock formations on both sides, but still don t have a full picture of what our hike is going to look like. Also, something that I just learned recently is that hillshading is almost always lit from the north. It looks nice, but is pretty inaccurate. At least as far as I know, the sun is never due north of the earth. 17

18 Switching to 3D shows the inherent value of being able to see the terrain in 3 dimensions. Seeing a picture of Half Dome is one thing, but being able to explore Yosemite in an interactive 3D virtual environment is invaluable. We have a much better idea of what to expect when we get there. One cool thing we added to Cesium in the past year is shadow approximation based on the position of the sun, so I could even plan out nice shady spots to camp in for my trip. Terrain from 18

19 For something a little different, let s look at a map of something that is not earth. NASA recently created an application to view data they collected for the Vesta asteroid. It is the second largest body in the asteroid belt and the brightest asteroid visible from Earth. From these two 2D maps, do we know what the asteroid looks like? I mean, we can kind of guess using the information from these legends. It looks like the radius in one direction is larger than the others, it s got some cool craters 19

20 Look at how irregular this spheroid is. It s got a little nub at the south pole that was completely hidden in both the 2D projections. This is an extreme case, but it does a good job highlighting how 3D gives us a more intuitive understanding of what we re looking at. In 2D, you have to represent data using X, Y and color. In 3D we can show positions in X, Y, Z. 20

21 3D also provides a natural path forward to 4D, or time dynamic visualizations. Satellite trajectories are a great way to showcase this. You might not be able to see it, but each of these trajectories have discontinuities in the 2D map. The satellites aren t teleporting over parts of the earth. The earth is rotating underneath of them. In 3D it is easy to show the earth rotating and the satellites following their orbits simultaneously. 21

22 Here is another time dynamic example. In this case, this is GPX data collected by a paraglider. For someone with no knowledge of paragliding, this looks like a very peculiar path to take with all the loopdyloops. 22

23 This is the same path being replayed in 3D. It turns out the paraglider isn t just trying to make himself dizzy. By interacting with the demo and changing the angle of the camera, we can see that he is actually riding thermals to climb higher. Super cool, right? 23

24 Now that we have a better understanding of what 3D has to offer, let s talk data. Data is the reason I believe the future of GIS will be 3D GIS. 3D data is being collected everywhere. The cost of collection is continuing to go down, and the size and detail of the datasets is continuing to go up. 24

25 There used to be this divide between BIM and CAD and GIS, but it s all converging. We now have the option to take highly detailed building models and visualize them intermingled with other spatial datasets. In this totally hypothetical example, we ve placed a power plant BIM model in the middle of downtown Austin, TX. BIM is inherently 3D, so we need 3D maps to visualize it. 25

26 LIDAR stand for Light Detection and Ranging. LIDAR sensors use lasers to determine the distance from the sensor to an object. High end LIDAR systems can collect several millions of points per second. However, there are a few different companies developing solid-state high-volume LIDAR sensors that will be available for less than $100. This, in combination with the growing use of drone technology will make 3D data collection easier than ever. And LIDAR is inherently 3D, so it only makes sense to display the data in 3D. And of course, LIDAR gives us 26

27 Point Clouds! This is a small point cloud data set of a church in Chappes France. LIDAR is everywhere, which means Point Clouds will be everywhere. 27

28 We re been working on some awesome new methods for rendering point clouds as well. Here is terrain point cloud, and with some fancy graphics rendering techniques 28

29 We re able to fill in the gaps to make the point clouds appear as a solid surface. This is something one of our research interns has been working on and will be available in Cesium soon. 29

30 Another method for capturing 3D data that has become increasingly popular is photogrammetry. Essentially you send someone or something around to take a thousands of pictures, and through computational photography methods we are able to stitch this data together and create a fully textured 3D mesh. There is no easy way to project this to 2D without losing most of the meaning of the data that was collected. One of the things I look forward to the most about photogrammetry is being able to explore without having to leave my couch. I spent a good half a day wandering around this Helsinki dataset on the right. 30

31 This is even more exciting with the prospect of VR. Say for example you re about to move across the country. Imaging being able to compare the view from 3 different apartments before you get there. 31

32 Photogrammetry also plays will with BIM. For example, here is a proposed Chemical Engineering Building model visualized in place in a photogrammetry model of Penn State s campus 32

33 There s a common theme here. Some types of data are inherently 3D, so 3D makes the most sense if we want to visualize them. This includes all types of volumetric analysis. 33

34 To finish up the discussion, I wanted to touch on a few common concerns that come up when we talk about using 3D maps 34

35 Here are the results of a twitter poll from Kelvin Wong a few months ago. Some of the main concerns for using 3D is hardware/software support, lack of 3D data, and interoperability. 35

36 3D hardware and software support is becoming less of an issue every year. This is a video of our Philadelphia reality model and the frame rate never drops below 20 frames per second. And most of the time the frame rate is closer to 50 and 60 frames per second. 36

37 The Cesium team also partners with the NORAD Tracks Santa program each Christmas to create a 3D app to see Santa s location in real time on Christmas Eve. This app reaches millions of users and we re able to gather some statistic from this app. Last year, the 3D app ran with a 92% success rate, which is phenomenal. This is up form a 20% success rate in More than half of these hits were from mobile devices such as iphones as well, so we were really excited about the broad range of WebGL support that is out there now. 37

38 Like I said before, with advances in data collection techniques like LIDAR and photogrammetry, 3D data is more accessible than ever before. That paired with the creation of new 3D open data formats means it will also be easier to share 3D data. In fact, one of the goals of our new cesium.com platform is to connect people that have 3D data with people who want to use 3D data. 38

39 And finally, 3D interoperability is here! The 3D Tiles open specification has already seen wide adoption in the industry, and is currently going through the OGC standardization process. There is a full ecosystem of tools out there. 39

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