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Welcome to Layerscape. Session A. Motivation. Why should a Researcher be interested? Let’s assume that you want to do something around data visualization that goes beyond cool and arrives at useful Why should an educator be interested?
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Welcome to Layerscape Session A
Motivation • Why should a Researcher be interested? • Let’s assume that you want to do something around data visualization that goes beyond cool and arrives at useful • Why should an educator be interested? • We want Learners engaged; and Layerscape at the end of the day is about interactive exploration • How hard is it? • Requisite skills: Know how to use Excel and PowerPoint. You’re set; just need to fill in a few details.
How do we proceed? • First we build a dataset • Then we import it into WWT • Then we play around with it • Then we create a Tour • Then we spruce up the Tour • Then we save and publish the Tour • Then we check the published Tour Onward!
Assumptions • All of the preparation can be done from http://layerscape.org • Download and install Worldwide Telescope • Download and install the Worldwide Telescope Add In For Excel • Bookmark http://layerscape.org • This is where Layerscape content is published and available to explore! • If possible spend some time using WWT • Explore the Look At Earth mode • Learn the basics of navigation including tilting your view • Notice the Layer Manager at the left, which toggles on/off using the button at the lower left. Onward!!
Resources • If you obtained this PowerPoint presentation from http://layerscape.org • Notice that there are two additional files associated • An Excel spreadsheet showing the data we use here • A WWT Tour showing the end result of this Session
Setting up your data 1 • Open Excel and… • In row 1 label columns A through H enter: • index, lat, lon, alt, color, magnitude, startdate, enddate • These will be mapped to some of the available WWT data attributes • A partial list of the available attributes is shown at the right • Create indices in column A from row 2 down • Values 0, 1, 2, 3, … to 1000 • Why am I doing this? • We’re generating synthetic data from scratch • Why? • Because you’ll have complete understanding of this data! • Which is the Researcher premise
Setting up your data 2 • That lat column will be latitude, then longitude, altitude, color, magnitude, start date, and end date; each row will be a data point or marker • Now the slightly painful bit: First make entries in columns j and k as shown at the right, rows 1 – 10. • (can highlight + copy + paste this table) So far
Setting up your data 3 For these formulas and any that follow: You may wish to cut the text from this PowerPoint presentation and paste it into the appropriate cell in an Excel spreadsheet. To paste: Right-click the destination cell and select Match Destination Formatting (M). • Create this formula in cell B2: =$J$1+A2*$J$8 • Create this formula in cell C2: =$J$3+A2&$J$9 • Create this formula in cell D2: =($J$7-A2)*100 • Cell E2 enter ‘white’ • Cell F2 enter this formula: =0.25 • Cell G2 enter this formula: =$J$10+A2 • Cell H2 enter this formula: =G2+3
Setting up your data 4 Select cells B2 through H2: Double-click the little box at the lower right of the highlighted cells.
Setting up your data 5 • This should fill in your data column all the way down to row 1002 (where the index = 1000). • Whew! Now you have 1001 data points; time to see what this looks like in WWT. To get it there you will use the Excel Add In for WWT.
Setting up your data 6 How the Excel Add In for WWT works, in three steps: • First you will tell Excel “this is the data I want to import to WWT” (by selecting it and clicking the Visualize Selection button on the Add In ribbon) • Second you make sure that the translation of the data from Excel to WWT is configured properly using the Layer Manager panel which appears automatically. • Third you “send” the data over by clicking the View in WWT button at the bottom of the Layer Manager panel. The next slides walk you through this process.
Import data into WWT 1 • Highlight cells A1 through H1002: • Click cell A1 • Use ctrl+shift+right-arrow to select the row • Use ctrl+shift+down-arrow to select the dataset • Select the WWT ribbon • Click Visualize Selection
Import data into WWT 2 How it looks
Import data into WWT 3 • The Layer Manager appears on the left side. • You can replace the default text in the Layer Name box; or you can leave it as-is. • Excel has looked at your Row-1 column labels and tried to guess what they correspond to in WWT terminology. • This is shown in the Map Columns tab of the center-left table: There is a correspondence between the two columns Data In The First Row and WWT Label. How did it do? • Your ‘index’ was not successfully mapped; it reads “Select One” with a dropdown menu. That’s ok; we don’t need to map ‘index’ to anything; we just used it to generate some of the other data • Your ‘lat’ was successfully mapped to Latitude; and so forth all the way down through startdate and enddate, which mapped to Start Date and End Date • We call this the Label Mapping Phase; and it is complete without you having to fix anything. Onward!
Import data into WWT 4 • In addition to the Map Columns tab in the Layer Manager there are two more tabs in that central table: Layer and Marker. We will use these later. For now they are fine. • Start WWT if it is not already running. • Back in Excel, in the Layer Manager panel on the bottom left there is a button that reads View in WWT. Click it.
Import data into WWT 5 • If all is well you should see the new layer in the WWT Layer Manager. In fact your perspective should have moved to the first data point in the list, somewhere west of Greenland. • Your data should appear as a sequence of white dots • You can zoom in with the mouse scroll wheel until you see the data points • You can select any row in your data table in Excel and click “Go To Viewpoint From Data” to fly to that data point in WWT • Henceforth we must maintain “dual thinking”: There is the data in Excel and there is the same data in WWT; a separate copy. The nice thing about Excel is that when your data changes, it reloads WWT automatically so the WWT copy stays current. • The Layerscape data model states that your WWT session is about visualizing the data and telling stories around it; and your Excel session is about manipulating and analyzing your data. • In fact Excel is acting as a Data Application or Data App. • It is where you apply your expertise to your data. • We encourage this connection/distinction between WWT and Data App because trying to make WWT both a visualizer and an analytical engine is overwhelmingly difficult, not to mention it re-invents the analytics wheel.
Zoomed out Import data into WWT 6 You may need to manipulate the perspective to see your data (a sequence of white dots). Excel tries to take you to the first data point, which is west of Greenland. Notice that in the Layer Manager in WWT this new data is given the name Sheet1_1. That name is a default provided by Excel which you can change to better describe the data. Moderate zoom
Data exploration 1 We’ll do three things with the data visualization you’ve built thus far: • Explore navigation and viewing perspective • Explore Time playback • Modify your data in your Data App (Excel) and see how this changes what you see in WWT
Data exploration 2 Suppose you want to know where a given data marker is in WWT. Excel supports this using Viewpoints. • Select row 1002 (the last row of marker data) • On the Excel WWT Ribbon click Go To Viewpoint From Data; you should arrive there in WWT at some zoom level. • Zoom in as far as possible to see this marker up close in relation to the background imagery • Image detail varies across the earth • Images shown in WWT are provided by bing maps.
Data exploration 3 Ok let’s pause to see the bigger picture for a moment. Session A is about mechanics; so granted the dataset is not too exciting. Once through this, however, session B will be about exploring multiple datasets in relation to one another in what we hope is an interesting way. This will require getting data from a variety of data providers on the web, then using our Excel machinery to bring them all into WWT.
Data exploration 4 • Fly around your data to get a sense of the transit and gradual change in elevation. • Very important: Hold down the center mouse button and drag the mouse around to become familiar with perspective tilting (bottom left figure). • Hold down the ctrl+shift keys and hold down the center mouse button, then drag the mouse to bring your perspective below the horizon. You are inside the earth looking up. The surface of the earth will disappear but your data will still be visible. • You can experiment with navigation in this mode. For example you can release the ctrl+shift keys and still navigate. Zooming out will cause you to “back out” of the earth on the far side (bottom right figure). You can also move using the left mouse button plus mouse drag, or with the arrow keys. • However notice that if (while looking ‘up’) you tilt your perspective in the usual way using center-mouse plus drag (no ctrl+shift), your perspective will pop back out to above the earth.
Data exploration 5 • If it is not open, open the Layer Manager in WWT (not Excel!) using this control at lower left: • Click on earth if necessary to expand it’s layer list • You should see an entry corresponding to your data, for example called Sheet1_1 • Click this layer; it should now be highlighted • Highlighting a layer is an important action; it means that this layer has the current “master influence” over how WWT is manipulating time. • While our layer has time data in it, this is currently not activated so all of our data appears ON in WWT. That is, it is all visible. • WWT maintains an internal clock, set by default to the current time, which is the WWT “now”. You can manipulate now by setting or causing it to play forwards or backwards at different rates. Controlling time is therefore an important WWT skill. • We will continue by doing some simple time manipulations to get a feeling for this feature.
Data exploration 6 • With your data layer highlighted (see previous slide) check both boxes at the bottom of the WWT Layer Manager: Time Series and Auto Loop • Time Series tells WWT to “pay attention” to time data built into this layer • Auto Loop says “when you reach the end of this layer’s time range, reset to the beginning of its time range” • Notice that our data begins on January 1 2000 and ends on September 30 2002. This is now reflected in the start and end dates above the slider bar in the Time Scrubber • Drag the Time slider back and forth • You should see only some of your data visible at any given moment, and the data should give the appearance of moving along from the starting point near Greenland to somewhere down South at the end point on the east coast of the US Oblique view of data implying motion from north to south
Data exploration 7 • Now we will cause the data to play back on its own, and we will move around as it does so • Click on the View control at the top. Notice this is a “split” button; click on the upper part where the View text is. • Note the Observing Time window which appears at the right side of the View ribbon • Click on the Fast Forward button six times until the text above the playback control reads “x1000000”. Time is now playing at one million times normal rate. • If you have Sheet1_1 highlighted and both Time Series and Auto Loop boxes checked then the playback should loop infinitely, and you can observe the progress of your marker sequence by navigating your perspective along the flight track. • You can increase the playback by another factor of ten, causing your marker playback motion to look more meteoric. • You can manually override the time by grabbing the time marker (in the time slider) and dragging it to a different location in the timeline • You can also play time backwards using the fast-backwards button. • When backwards-play reaches the beginning of the active time range it will hold there. To get it to repeat you must manually drag the time slider to the end of the time range to reset the backwards-time playback. • With the playback looping, practice following your marker through space by manipulating your perspective. This eventually gets tiresome but we’ll address that when we build a Tour. 6 clicks
Data exploration 8 • The last part of data exploration will be modifying the dataset inside Excel and seeing these changes reflected in the WWT visualization. • Change cell E2 to the following formula, an “if statement” construction in Excel that chooses a color based on the altitude of the marker • Once the formula is entered the cell should read “white”. Double-click the lower right corner of the cell to get it to propagate down the entire column. • The change should be reflected in the marker color in WWT. As the marker flies south its altitude drops and it changes color.
Data exploration 9 • Make the marker easier to see by typing in a larger magnitude. Use the same procedure as on the previous slide: Make all the magnitudes equal to 2 by typing ‘=2’ in cell F2. Then replicate that down the entire F column. • Optionally you can do further modifications to you data. For example you could make the trajectory a bit wiggly and a bit random by substituting the formula below in column C (the example is for cell C2). =$J$3+A2*$J$9+0.5*SIN(A2/10)+RAND()/2-0.25
Data exploration 10 • Again note that as you make changes the data is updated automatically because the Excel Add In considers itself to be linked to WWT. • One note of caution: If you decide to make multiple layers in WWT out of a single block of data in Excel you can run into problems. • It is best for now to avoid this practice; for example you can create multiple copies of your source data by pasting the contents of one sheet into successive additional sheets. • The sheets are seen as tabs at the bottom of the Excel spreadsheet. • You can right-click on these sheet tabs and rename your sheets to indicate what each one is for.
Creating a Tour 1 • Now we’ll make a narrative Tour that tells a story around your data. • Start in WWT with your data already loaded as a Layer. From the Explore menu select New + Slide-Based Tour. This brings up a Tour Properties form with lots of possible details to fill in. • Give your Tour a descriptive title but for now do not enter any other data in the Tour Properties form. Click Ok. • The slide sorter bar appears at the top of your screen. Click Add New Slide. A new slide appears with a thumbnail taken from your current perspective.
Creating a Tour 2 • Slide thumbnails carry a lot of detail. The number at the bottom shows how long the slide takes to run, in seconds. Click on this and use the down arrow to reduce the slide duration from 10 seconds to four seconds. You can also click on the number itself and type in a new slide duration in minutes, seconds, and tenths using the keyboard. • The black bar below the thumbnail can have text. This is useful for longer Tours to keep track of where you are, particularly if the thumbnail doesn’t give that away. Click in the text area and type in some text. • The two triangles at left and right above the slide thumbnail are flags to indicate whether you are at the beginning or the end of the slide. In this example the left triangle is illuminated so you are at the beginning of the slide. Click on the right triangle to illuminate it (the left triangle is then dark). • The three changes described above are shown in the lower figure at the right. These are the first basic manipulations to a Tour slide. We will continue with a couple more which are accessed using the right mouse button, which brings up a menu of slide editing controls and actions.
Creating a Tour 3 Your first Tour slide will play back from your starting perspective. We have modified it to run for four seconds, and technically your Tour is done. But before we save it let’s add one more thing. • Navigate to a slightly different perspective in WWT. • Right-click on your first slide and select Set End Camera Position. You do not have to have the right triangle selected (yellow) to do this. • You can use this same right-click menu to see where your slide starts (Show Start Camera Position) and where it ends (Show End Camera Position). Click the play button to the left of your Tour slide to verify that your Tour runs properly. • Click the Save button at the upper right and save your Tour to your computer’s file system. You can give it an appropriate name. We have named and saved this Tour at the Layerscape website under the name Transit Tour from Workshop A
Creating a Tour 4 • Building Tours is now a matter of appending additional slides. If the next slide begins at a completely new location then WWT will transit between the end perspective of the current slide to the start perspective of the new slide automatically. This can take a few seconds. • Alternatively you can make the next slide start where the current slide leaves off. The simplest way to do this is to go to the current slide’s end position and click Add New Slide. • You can also use the rt-click menu and select Duplicate Slide at End Position. This alternative has some additional advantages but can be a little tricky to master; so for now we use the Add New Slide method exclusively. • We are assuming your data is currently not activated as a Time Series; that is, the Time Series box is not checked. This means that the entire transit from Greenland to the US is visible. Add a New Slide that moves from your perspective at the end of slide 1 to a vantage point looking down on your data. (Again use Set End Camera Position to accomplish this.) Make the slide duration six seconds and add the slide caption Go To Data. Save!
Creating a Tour 5 • At the end of your Tour add a third and final slide. Make the Start and End Camera Positions the same (simply do not add a new End Camera Position) and make the duration five seconds. • This adds a “hold” on the end of your Tour so that it does not end abruptly. • Add the slide caption ‘End Slide’ and Save the Tour. • We’ll consider this a Tour well done and move on to the next stage of Tour building, which will include making your Tour track the playback of your data with time.
Making your Tour better 1 Before jumping in to more How To consider the task at hand as a challenge: How might you make a Tour slide that follows your data as it plays out in time as a flight path or trajectory? The key idea is that slide Start Camera Positions and End Camera Positions encode WWT time values as well as spatial perspective.
Making your Tour better 2 • In Tour playback: A particular data Layer can either be Time Series active or not. Our flight-track data is not Time Active; but we want to keep it that way and also look at it in active mode. Therefore we will create a second copy of our Layer data which is Time Series active. • To do this: Right click on the Layer in the Layer Manager, select Copy, then right-click on the earth and select Paste. This will bring up a Data Visualization Layer wizard. We can re-name this copy layer on the Welcome panel and then click Next.
Making your Tour better 3 • Click Next in the Wizard three times to arrive at the Markers panel. Check the box that says “Show Far Side Markers”. This makes markers visible from an upwards-looking viewing perspective which will be important shortly.
Making your Tour better 4 • Click Next in the Wizard two more times to arrive at the Date Time panel. Notice that there is a Time Decay slider which you can set as you like. When a given data point (marker) reaches its own End Date it will gradually fade out over <Time Decay> days. • If you set this to the minimum value of .0002 the marker will vanish instantly. • If you set it to a large value like 64 the marker will take quite some time to fade out • Notice that the Begin Date Range and End Date Range are correctly calculated based on the earliest and latest times present in your Layer data. • You need not have these data points sorted in chronological order for this Begin / End calculation to work correctly.
Making your Tour better 5 • Click Finish in the Wizard and note that your new layer now appears next to your original in the Layer Manager • You can re-open the Wizard and modify your Layer’s configuration at any time: Right-click on the Layer in the Layer Manager and select Properties, then select the tab you need. • Use this method now to set your Decay Time for the new layer to 32 days • Highlight the new layer by clicking on it and check the Time Series checkbox at the bottom of the Layer Manager • You now have a Time Series active version of your flight track data. • Un-check the box in the Layer Manager next to your original data. That data should no longer be visible.
Making your Tour better 6 • Add a new slide to your Tour and position it as third-in-line from the start. • Click on Add New Slide • Label it Time Slide • Set its Duration to 21 seconds • Simply drag the new slide to where you want it to be • Ensure that your original Layer is de-selected, that the new Layer is selected and that it has Time Series checked. • The Time Slider should have start and end dates as shown at right • Drag the Time Slider back and forth to see your data moving along its flight path. • Locate the beginning of the flight path and move your viewing perspective to see this starting point obliquely, for example as shown here.
Making your Tour better 7 • Now the nifty part: Right-click on your Time Slide and select Set Start Camera Position. • Use the time slider to set the WWT to the end of your Layer’s time range • Maneuver your perspective so that you are now looking at that data at the end of the Time Range • Right-click on your Time Slide and select Set End Camera Position • Save your Tour • Play the Tour to see two things: • How did WWT manage the transition from the end of slide 2 to the start of the Time Slide • How does the Time Slide playback look? Does it track the data well or does it lose track of the data at some point? • If the Time Slide does lose track of your data (perhaps only to regain sight at the very end of the slide) you can re-do the setting of the start and end camera positions. • You may need to pull back your perspective • It may also help to try and look in the direction of the flight track • When I tried this I noticed that the start of my End of Tour slide was disconnected from the end of my Time Series slide; there was another transition that I did not want. Next we will remedy this.
Making your Tour better 8 • Click on the Time Slide and click on the upper-right triangle. This takes you to the end-position of this slide. • Right-click on the End of Tour slide that follows and choose Set Start Camera Position. • You have now adjusted your End of Tour slide to the same perspective as the end of your Time Series slide. • Save the Tour and play it again to make sure you are satisfied with everything.
Making your Tour better 9 • The last step is to add a text box that includes a time indicator. Start by selecting the Time Slide and the start camera position (upper left triangle on the slide) • Click on the Text icon at the upper right to bring up a Text Editor • Type in some text but do not hit Save just yet. • At the upper right of the Text Editor is a Special Items icon with a drop-down menu. • Select Date • Select Latitude • Select Longitude • Space these out in the text box using spaces or carriage returns • My end result is shown at the right • Now click Save at the upper left of the Text Editor • Position your text • You can drag and resize it as in Power Point
Making your Tour better 10 • Save and Play your Tour • You should now see your Time Series data play back with a dynamic display of date, latitude and longitude • Congrats! You have learned the fundamentals of Tour authoring in WWT • There are many advanced features which we leave for another session • Now let’s publish your Tour at Layerscape
Publishing your Tour 1 • This needs expansion • Gotta have a Windows Live ID • Gotta go to http://layerscape.org and Agree to the TOU • Click Publish, choose General Interest • Go through the metadata: What it means • Done? Great; but let’s verify: • Search for and find your Tour • Run it from LS to make sure it is there safe and sound • Email us the link!!! • We’ll send you an XBOX, we promise!!! • Actually we’ll send you either an Xbox or an epiphyte, our choice
Where to from here? Session A was a lot of stuff; so again congratulations on getting through it all! In Session B we will explore the visualization potential of Layerscapein an Education setting. We will download a Tour and practice disassembling the data, then reassembling a new Tour from that. In Session C we will follow a research arc: We pose some questions, choose one of them to try and answer, and then hunt down related data on the web and get a copy of it. From there we will see what is necessary to bring that data into WWT. Send feedback or questions to wwtepm@microsoft.com; we would be delighted to hear from you! You can also take our online survey.
Session B Welcome to Session B. Here we will work more with Tours and Tour content (data) in the context of an Education session. We first remind you that the WWT menus are actually dual buttons: The text (“Explore”, “Guided Tours” etcetera) gives you one result when you click on it. The little down-arrow below the text gives you something else: A dropdown menu with many options. We indicate the main text menu using that text (“Explore”) and we indicate the sub-menu by appending a small v subscript to the text (“Explorev”). Please begin by downloading a Tour from Layerscape (Save it as a file on your computer): http://www.layerscape.org/Content/Index/1193 Open WWT and Explorev> Open > Tour… to load the above Tour in Edit Tour mode. To ensure you are Editing and not Viewing the Tour: Click on Guided Toursv. If the text “Edit Tour” is visible in the drop down list: Click it. You can still watch Tours play back in Edit mode; but you can also Edit the Tour, which is what we want. This is an important detail to remember if you find yourself unable to edit a Tour!
Extracting GEOMETRY • Ensure the Layer Manager is open: Viewv > Show Layer Manager. • In the Layer Manager click the + sign to the left of Earth to expand the layers attached to the Earth. • Right click on the Layer called “Vector Field 7/12/2013 8:28:56 PM” and select Copy. • Open Excel, create a new spreadsheet, right-click on Cell A1 and select Paste. This should create entries in cells A1 through 12190. Each row is one of the vectors you see at the beginning of this Tour.
GEOMETRY continued 2 • Notice that you can now save this Excel spreadsheet as an Excel file. Do so now, then halt Excel and halt Worldwide Telescope. Then re-start Excel, load the spreadsheet you just saved, and re-start WWT (without loading the Tour). The point here is to simulate “starting from scratch” after recovering data from a WWT Tour. • Now reverse the process: Highlight cells A1 – C12190 in Excel, right-click, and select Copy. In WWT open the Layer Manager, right-click on the Earth, and select Paste. This is the “obvious” part of cutting and pasting from Excel and it was covered in Part A of this Tutorial as well. • Notice that your Paste has brought up a Layer Properties Wizard. You may wish to enter a new Layer name such as “Recovered Vector Field”. The click the Next button three times to arrive at the Markers configuration page. Click the “Show Far Side Markers” check box. Then click Finish. • The vector field should now appear, as it did before in the Tour, off the southwest coast of Australia. You can go explore this data; but you may find that you can not swing down underneath to view it from below. This capability must be enabled so that your tilt ability does not halt at horizontal. Click Viewv > Allow Unconstrainted Tilt. Now using (middle mouse click + drag) or if this does not work (Ctrl key + right mouse click + drag) you should be able to change your viewing perspective angle to below the surface of the earth looking up. You should still be able to see your vector field from below because you clicked on the “Show Far Side Markers” checkbox in the previous step.
GEOMETRY continued 3 Returning to the Excel spreadsheet: Notice that unlike in Session A there are no latitude or longitude columns. Rather each vector is represented as a row containing an entry like this: That “LINESTRING((109…” entry is a format known as Well Known Text (WKT). For more on this see the Wikipedia article here: http://en.wikipedia.org/wiki/Well-known_text
GEOMETRY continued 4 Notice also that the column header for the WKT (Excel spreadsheet Column A) reads “geometry”. WWT interprets this to mean “Rather than latitude and longitude columns we will use WKT entries to provide position locations in this column. Our example LINESTRING entries in WKT are triples separated by commas: First longitude, then latitude, then altitude. Notice this is a rather tricky “gotcha” if you happen to be accustomed to writing latitude then longitude.
GEOMETRY continued 5 This concludes our introduction to WKT and GEOMETRY. It expands our drawing capabilities in WWT beyond markers to lines; and we will visit a further extension to polygons in a later section of this workshop. Notice that, like Markers, GEOMETRY objects can have color and date attributes (Columns B and C in the spreadsheet). They can also have a magnitude attribute but this has no actual effect on how the WKT objects are rendered.