When Google released Google Earth as a free download several years ago, people quickly learned what Keyhole Markup Language (KML). GIS professionals were quick to build translators to convert their data from several different formats into KML for viewing in Google Earth. The better of these tools let the user maintain the mapping symbology from their GIS software platform into the KML.
In the last couple of years, and enormous amount of geospatial data has been converted to KML to be viewed in Google Earth. In response, may geospatial visualization packages started to let users load KML into their own viewers. So where does KML actually fit into the whole geospatial realm? Will it become a standardized way to store geospatial data?
KML has a couple of things going for it. It’s based on XML and is well documented. It represents a pretty good method for encoding spatial data and symbology (and, to a lesser extent, attribution). But by far the biggest thing KML has going for it is that it is native to Google Earth. To that end, KML is really oriented toward defining displayable geospatial data. I have yet to see any code that performs any geosprocessing on KML, and there is a lot of overhead with KML then with, as an example, a shapefile.
So where does KML fit in compared to GIS data? I think that the answer to that lies with what people with a GIS background typically do with KML. They dynamically generate it from traditional geospatial data stores (shapefiles, geodatabases, etc), and they allow their own viewers to load and see KML files.
KML is serving the role that is usually found within GIS software. Whenever a file is loaded, a symbology class is assigned to it to define how the data will look in the map. Most people, other than programmers, never actually see this information. They only see the windows that let them alter the symbology of data, and the data itself. Some GIS packages allow users to save “layer” information that references the originating spatial data (an ESRI ‘.lyr’ file is an example).
So, in conclusion, it appears that KML represents what is typically in in-memory representation of geospatial and symbology data in most geospatial software applications, offering KML authors a very unique, open, specification at that level of representation.
Sunday, August 19, 2007
Targeted Solutions with ArcGIS Explorer
ArcGIS Explorer is described by ESRI as being a “lightweight client for ArcServer”. Interestingly, ArcGIS Explorer is not actually tied to any other ESRI products. It and an SDK to develop customized tasks are free to download, and (as far as I can tell) free to deploy.
What this means is that ArcGIS Explorer can be used as an interface for all sorts of geospatial applications in a manner similar to Google Earth, Virtual Earth, and WorldWind using free and open source geospatial software components. Any processing logic that can be connected to any of these earth browsers can similarly be connected to ArcGIS Explorer. The current strength of ArcGIS Explorer in this category is the ability to customize the interface to hold any new toolsets.
I am really hoping to be able to work on some targeted geospatial applications that can very cheaply take advantage to this visualization platform.
What this means is that ArcGIS Explorer can be used as an interface for all sorts of geospatial applications in a manner similar to Google Earth, Virtual Earth, and WorldWind using free and open source geospatial software components. Any processing logic that can be connected to any of these earth browsers can similarly be connected to ArcGIS Explorer. The current strength of ArcGIS Explorer in this category is the ability to customize the interface to hold any new toolsets.
I am really hoping to be able to work on some targeted geospatial applications that can very cheaply take advantage to this visualization platform.
Tuesday, January 09, 2007
Google Earth as a Geographic Information System
The first work that I did with Google Earth and KML was to build a converter in ArcMap that would export all of the selected layers out to KML. We used this for an emergency response tool set that worked in ArcMap. The idea was that the mapping would be managed by someone trained in using GIS who would them automatically kick-out KML updates to a server to be viewed using GE networklinks by commanders.
This worked really well, but at the time, I wondered if it would be possible for Google Earth to act more as an interactive partner rather than a static viewer. When it came to having GIS capabilities, Google Earth has never really been considered (for good reason).
However, the more I thought about it, the more I wondered if GIS type functions used for command and control applications could not be accessed and used by Google Earth. What I really wanted to do was to used open-source functions with not license restrictions to create a GIS back end, and then have Google Earth act as the interface.
When Google Earth officially announced that they had a COM API, I started looking a bit more at the possibility of being able to interact more effectively with Google Earth. I noticed some update functions that I thought might help . I first mentioned this in the beginning of December when I wrote New Google Earth API Allows for GIS Type Interaction.
I was able to use this new API function to select coordinates directly from Google Earth. This has huge implications, as I can use these coordinates to Select and Identify GIS data. I can now marry this capability with Shape2Earth, which allows me to Import GIS directly into Google Earth.
So, now I can load GIS data directly into Google Earth, and I can query and select this data using Google Earth. The next thing I want to do is actually create data and launch geoprocessing functions from Google Earth. Here is how I do that.
To start with, I have the Google Earth Render window embedded in my application (I'm using GoogleEarthAirlines to do this), and I have loaded GIS data using a modified form of Shape2Earth.
To show how I can interact with Google Earth similar to a GIS, I'll walk through an emergency response scenario. I am given a building at which there is an incident, I can do a quick search using either the building name, ID, or a coordinate. I use MapWindow GIS components to search for the building information in the shapefile, and then zoom to the location.
When I get to the area of interest, I want to Cordon (buffer) off the affected area. I first select my Cordon tool and click on Google Earth to set the center point (I could also select the building and create a cordon around that). The point (or selected feature) is sent to my cordon tool. I then select the size of the cordon, the measurement units (feet, meters, etc.), and the number of rings I would like. In this case, 2000 feet with 1 ring.
MapWindow GIS components are used to create the buffer (shown below). Shape2Earth creates a kml file and a shapefile to represent the new geospatial data set.
The next thing I want to do is determine what buildings are impacted by this event. MapWindow GIS components select the buildings using the cordon polygon. Shape2Earth modifies the color of the kml and reloads is quickly into Google Earth (see below). The same process is used to select affected roads, and to set up traffic control points to isolate the area.
Since my GIS data and KML are linked, and I can grab coordinates off of the map, I can change the status of buildings simply by clicking on them in Google Earth (note that the orientation of Google Earth does not matter, not does the location that you click). This brings up a dialog box that lets me edit the GIS data which also changes the color of the KML.
Above, GIS data is selected and edited directly in Google Earth.
Combining the visualization of Google Earth with the power of GIS leads to some very effective capabilities. The data can be immediately served out to other clients, such as another Google Earth as seen in the graphics below.
GIS Data viewed and edited in Google Earth above
Created GIS data viewed in another Google Earth Client in near real-time
Besides being able to edit GIS attribute data, we can create GIS data by digitizing directly on Google Earth. The graphic above shows a sketched route that is converted to a shapefile.
This worked really well, but at the time, I wondered if it would be possible for Google Earth to act more as an interactive partner rather than a static viewer. When it came to having GIS capabilities, Google Earth has never really been considered (for good reason).
However, the more I thought about it, the more I wondered if GIS type functions used for command and control applications could not be accessed and used by Google Earth. What I really wanted to do was to used open-source functions with not license restrictions to create a GIS back end, and then have Google Earth act as the interface.
When Google Earth officially announced that they had a COM API, I started looking a bit more at the possibility of being able to interact more effectively with Google Earth. I noticed some update functions that I thought might help . I first mentioned this in the beginning of December when I wrote New Google Earth API Allows for GIS Type Interaction.
I was able to use this new API function to select coordinates directly from Google Earth. This has huge implications, as I can use these coordinates to Select and Identify GIS data. I can now marry this capability with Shape2Earth, which allows me to Import GIS directly into Google Earth.
So, now I can load GIS data directly into Google Earth, and I can query and select this data using Google Earth. The next thing I want to do is actually create data and launch geoprocessing functions from Google Earth. Here is how I do that.
To start with, I have the Google Earth Render window embedded in my application (I'm using GoogleEarthAirlines to do this), and I have loaded GIS data using a modified form of Shape2Earth.
To show how I can interact with Google Earth similar to a GIS, I'll walk through an emergency response scenario. I am given a building at which there is an incident, I can do a quick search using either the building name, ID, or a coordinate. I use MapWindow GIS components to search for the building information in the shapefile, and then zoom to the location.
When I get to the area of interest, I want to Cordon (buffer) off the affected area. I first select my Cordon tool and click on Google Earth to set the center point (I could also select the building and create a cordon around that). The point (or selected feature) is sent to my cordon tool. I then select the size of the cordon, the measurement units (feet, meters, etc.), and the number of rings I would like. In this case, 2000 feet with 1 ring.
MapWindow GIS components are used to create the buffer (shown below). Shape2Earth creates a kml file and a shapefile to represent the new geospatial data set.
The next thing I want to do is determine what buildings are impacted by this event. MapWindow GIS components select the buildings using the cordon polygon. Shape2Earth modifies the color of the kml and reloads is quickly into Google Earth (see below). The same process is used to select affected roads, and to set up traffic control points to isolate the area.
All of these new data are saved as kml with associated shapefiles as described in Importing GIS Data into Google Earth.
Since my GIS data and KML are linked, and I can grab coordinates off of the map, I can change the status of buildings simply by clicking on them in Google Earth (note that the orientation of Google Earth does not matter, not does the location that you click). This brings up a dialog box that lets me edit the GIS data which also changes the color of the KML.
Above, GIS data is selected and edited directly in Google Earth.
Below, the KML file is update and reloaded.
Combining the visualization of Google Earth with the power of GIS leads to some very effective capabilities. The data can be immediately served out to other clients, such as another Google Earth as seen in the graphics below.
GIS Data viewed and edited in Google Earth above
Created GIS data viewed in another Google Earth Client in near real-time
Besides being able to edit GIS attribute data, we can create GIS data by digitizing directly on Google Earth. The graphic above shows a sketched route that is converted to a shapefile.
Importing GIS Data into Google Earth
Google Earth has often been described as a geospatial data browser. The reason for this is simple ... while Google Earth is fantastic for visualization, it does not do (nor has it been intended to do) many traditional GIS tasks. As an example, you cannot really query GIS data or directly access attribute data. You also cannot edit or manage geospatial data. Google Earth is really intended to do one thing very well, and that is to display geospatial data on a visually appealing framework. There have been many efforts by a lot of people to try and wring GIS type capabilities out of Google Earth. Many of the more successful ones used a combination of network links and data embedded in the description tag (and visible in the callout balloon) to link points to other data available on servers. What would really make things easier would be if users could click on Google Earth and grab coordinates. If we could do this, then we could attach geospatial capabilities behind Google Earth to make it act as a GIS interface. The new Google Earth API (and a lot of trickery) have now made that possible. The first thing I wanted to do was to be able to create toolbars that could be accessible in Google Earth. Since I could not do that, I started looking into grabbing the Google Earth Windows handle so that I could embed the viewer in my application. I had a 75% solution in the bag when I stumbled on GoogleEarthAirlines. GoogleEarthAirlines is an ActiveX control written in Delphi that does just what I was planning to do. When I found this, I put my control on the backburner and started using this. The graphic below shows the GoogleEarthAirlines control in my application.
Shape2Earth is used to create height values of GIS Data
Basic colors for the output KML are selected
A Unique ID is selected from the Attribute field. This will be used to attach to databases through Google Earth
The steps above walk through loading a shapefile into the Google Earth GIS application. Now, we use our trickery to click on Google Earth and grab a coordinate. This is done using the method described here.
The great thing about this method is that it does not matter what the orientation of Google Earth is. It will always return the coordinate that you clicked.
The same method can be used to select multiple features, as is shown below.
Select Tool lets the user drag a selection box across Google Earth
MapWindow components are used to select the geospatial features and display their attributes
The plan now is to link GIS data with KML. KML will act as the layer file that does nothing more than render my GIS data. to get the GIS data into Google Earth, I used a modified form of Shape2Earth. Shape2Earth converts the shapefiles to KML, and then writes an XML file that links the two files together.
Shape2Earth is used to create height values of GIS Data
Basic colors for the output KML are selected
A Unique ID is selected from the Attribute field. This will be used to attach to databases through Google Earth
The steps above walk through loading a shapefile into the Google Earth GIS application. Now, we use our trickery to click on Google Earth and grab a coordinate. This is done using the method described here.The great thing about this method is that it does not matter what the orientation of Google Earth is. It will always return the coordinate that you clicked.
In the graphic below, I have selected the ID button, and then clicked on a building. The application uses geoprocessing capabilities provided by the open source GIS application MapWindow. It loads the selected shapefile, and uses the coordinate to determine what has been selected. The result is the ability to directly access geospatial attribute data by clicking directly in Google Earth.
The same method can be used to select multiple features, as is shown below.
Select Tool lets the user drag a selection box across Google Earth
MapWindow components are used to select the geospatial features and display their attributesNow that we can do some basic GIS type functions directly in Google Earth, we can start doing more sophisticated workflows. The next step is to actually create GIS data directly in Google Earth. That has already been done, and will be posted here shortly.
Thursday, January 04, 2007
Shape2Earth Version 1.0
After three beta testing periods, and a lot of new enhancements and optimizations, Shape2Earth Version 1.0 has been released for download at http://shape2earth.com/.
Shape2Earth uses freely available Geographic Information System (GIS) software to convert shapefiles into color coded Keyhole Markup Language (KML) files for visualization in Google Earth.
Shape2Earth provides a powerful tool for people and organizations who do not wish to invest thousands of dollars in professional GIS software in order to create powerful and compelling visual information. Shape2Earth can also quickly expand the capability of those who already have a significant investment in GIS for the lowest price possible.
Download Shape2Earth, and then look at the online blog to see what shape2earth can do for you.
Shape2Earth uses freely available Geographic Information System (GIS) software to convert shapefiles into color coded Keyhole Markup Language (KML) files for visualization in Google Earth.
Shape2Earth provides a powerful tool for people and organizations who do not wish to invest thousands of dollars in professional GIS software in order to create powerful and compelling visual information. Shape2Earth can also quickly expand the capability of those who already have a significant investment in GIS for the lowest price possible.
Download Shape2Earth, and then look at the online blog to see what shape2earth can do for you.
Physiographic Regions of the U.S.
Saturday, December 09, 2006
Labeling KML Part 2
I wrote previously on how Shape2Earth can now create center-points from polygons that can be used for labeling. The next thing I need to do is create the same functionality for lines. This is a bit trickier than for polygons. Imagine using the bounding envelope for the Missouri River to create a center-point to label the River. Its just not going to be in a very effective place.
The idea I am going to take a crack at is to use one of the points in the feature itself. I'll probably just pick the middle point and use that as the label. This should get the label reasonably close, and then let users make minor adjustments to its location in Google Earth.
The idea I am going to take a crack at is to use one of the points in the feature itself. I'll probably just pick the middle point and use that as the label. This should get the label reasonably close, and then let users make minor adjustments to its location in Google Earth.
Thursday, December 07, 2006
New Google Earth API Allows for GIS Type Interaction
I am not sure that this is what the Google Earth engineers had in mind when they released it, but new COM API exposes a method called “GetPointOnTerrainFromScreenCoords”.
If you pass this method normalized screen coordinates from the GE Render window, it will return the Latitude, Longitude, and elevation of that point in Google Earth. This opens up an enormous amount of potential for using Google Earth as your GIS interface.
Google has always maintained that they are not a GIS, and they are right. But they have a great visualization system. All that is needed is a way to interact with their interface in a way that makes sense for GIS types of applications. All of the GIS activity can than go on behind the scene.
As an example, I can now click anywhere on Google Earth and capture the coordinates. I can also drag a rectangle across the screen and define its actual location within GE. I can then pass this data back to GIS representation (such as a shapefile) of the loaded KML data. The result is a color coded selection set of data, or a new window that holds whatever feature data I would like to see from another server (or local data).
I can also use the coordinate to calculate a buffer that is loaded in as KML. I can also use this data to select other data.
You can also create very quick sketches directly in Google Earth that can be saved as shapefiles, or sent out to other clients for collaboration. Much more to come on this.
If you pass this method normalized screen coordinates from the GE Render window, it will return the Latitude, Longitude, and elevation of that point in Google Earth. This opens up an enormous amount of potential for using Google Earth as your GIS interface.
Google has always maintained that they are not a GIS, and they are right. But they have a great visualization system. All that is needed is a way to interact with their interface in a way that makes sense for GIS types of applications. All of the GIS activity can than go on behind the scene.
As an example, I can now click anywhere on Google Earth and capture the coordinates. I can also drag a rectangle across the screen and define its actual location within GE. I can then pass this data back to GIS representation (such as a shapefile) of the loaded KML data. The result is a color coded selection set of data, or a new window that holds whatever feature data I would like to see from another server (or local data).
I can also use the coordinate to calculate a buffer that is loaded in as KML. I can also use this data to select other data.
You can also create very quick sketches directly in Google Earth that can be saved as shapefiles, or sent out to other clients for collaboration. Much more to come on this.
GIS for Google Earth: Final Testing
[Note: Final testing for Shape2Earth is complete. Shape2Earth Version 1.0 is has been released as shareware, and is available for download at http://shape2earth.com]
The final beta version of Shape2Earth is ready for testing. I am particularly interested in international users, as I have had some issues with coordinates being written without decimals, and I want to make sure that is working.
This version also has a licensing manager built in to it. It will operate in full mode for 7 days, but then must be licensed.
Beta testers will receive the license to extend the use of the software until the final release.
Any interested persons may contact me at Sabin21@gmail.com
The final beta version of Shape2Earth is ready for testing. I am particularly interested in international users, as I have had some issues with coordinates being written without decimals, and I want to make sure that is working.
This version also has a licensing manager built in to it. It will operate in full mode for 7 days, but then must be licensed.
Beta testers will receive the license to extend the use of the software until the final release.
Any interested persons may contact me at Sabin21@gmail.com
Labeling GIS Data with Shape2Earth
One of the most requested functional additions for Shape2Earth has been the ability to label polygons. This is now possible with the use of a centroid function that creates a point in the middle of the polygon for the label.
In the example below, I will be labeling major lakes in the United States.
First, I open up Shape2Earth from MapWindow GIS
If I want there to be only text, I make the size of the icon zero, and do not add a label rollover. If I want to make it a bit fancier, I can select one point for the label, and another that is displayed when the user rolls over it.
Finally, I can select which attribute field I want to use to label each polygon. I can also select to sort the features so that they will be displayed in alphabetical order.
In the example below, I will be labeling major lakes in the United States.
First, I open up Shape2Earth from MapWindow GIS
Then, from the Properties tab, I select the points that I want to use for the labels using the Enhanced Point Selector dialog box.
If I want there to be only text, I make the size of the icon zero, and do not add a label rollover. If I want to make it a bit fancier, I can select one point for the label, and another that is displayed when the user rolls over it.
Finally, I can select which attribute field I want to use to label each polygon. I can also select to sort the features so that they will be displayed in alphabetical order.
A simple result is show below.
These methods can be used to make some rather sophisticated views in Google Earth
Tuesday, December 05, 2006
Personal Geodatabase Feature Classes in Shape2Earth
Another interesting thing that I have been poking around at for some time is the ability to read ESRI Access Personal Geodatabases directly from their binary representation without the need for ArcObjects. The trickiest part of this was having to interpolate curves. I have this working to a reasonable degree.
The current prototype exports PGDB feature classes to KML, Shapefiles, and into SQL for importing GIS data into PostGIS, and has been tested with PGDBs created with ArcGIS 9.1 and 9.2. This opens more data for use with Shape2Earth.
I have been assuming that the same binary structure used in Access databases are also used by ArcSDE, but have not had the chance to test this theory out.
This same method could be used to create and edit Personal Geodatabase (and ArcSDE for that matter), but I doubt I’ll ever have the time to see this through.
The current prototype exports PGDB feature classes to KML, Shapefiles, and into SQL for importing GIS data into PostGIS, and has been tested with PGDBs created with ArcGIS 9.1 and 9.2. This opens more data for use with Shape2Earth.
I have been assuming that the same binary structure used in Access databases are also used by ArcSDE, but have not had the chance to test this theory out.
This same method could be used to create and edit Personal Geodatabase (and ArcSDE for that matter), but I doubt I’ll ever have the time to see this through.
Monday, October 30, 2006
Shape2Earth Beta 3
[UPDATE:
Shape2Earth Beta 3 input provided an enormous amount of help in the finalization of Shape2Earth. Shape2Earth Version 1.0 is now available for download at http://shape2earth.com]
I have recently been able to start work on Shape2Earth Beta 3. Work so far has focused on a couple of fixes and enhancements or adjustments to current functionality.
I am cleaning up the 3D section and adding the ability to use Z values. Clamping features to the Earth will happen automatically if there are no height values (greater than zero) for all of the points in the feature.
Shape2Earth has better handling for zero geometries, which are very common in data that is typically derived from CADD. Previously, if there were any features with zero geometry, the resulting kml document would be blank of any data.
I would like for Shape2Earth to be able to handle the sorting of features based on an attribute to be a bit more user friendly. It currently requires the user to set three different values in three different areas to work. This will be consolidated into a single area.
I will probably build a separate form that can be used to better control the symbology of the features. Users will have an easier time selecting point symbols, and will have greater control over setting the colors for lines and polygons.
I have added a centroid function that creates a ‘center-point’ for polygons. This can be used for labeling.
I am adding better instructions on how to make sure that the shapefile is projected properly.
Users will also be able to only export a subset of the features in the feature class (such as only those in the current view, or those that have been selected).
Users will be able to export the view as a PNG overlay image.
I am also doing some experimenting with collada models. In some cases, lifelike models can be used to represent the features from the shapefile. This can be used in conjunction with the new features found in KML 2.1 to display features at different distances as different symbols (a generic circle at a great distance would be displayed as a model when the user gets close enough to see the model appropriately).
Shape2Earth Beta 3 input provided an enormous amount of help in the finalization of Shape2Earth. Shape2Earth Version 1.0 is now available for download at http://shape2earth.com]
I have recently been able to start work on Shape2Earth Beta 3. Work so far has focused on a couple of fixes and enhancements or adjustments to current functionality.
I am cleaning up the 3D section and adding the ability to use Z values. Clamping features to the Earth will happen automatically if there are no height values (greater than zero) for all of the points in the feature.
Shape2Earth has better handling for zero geometries, which are very common in data that is typically derived from CADD. Previously, if there were any features with zero geometry, the resulting kml document would be blank of any data.
I would like for Shape2Earth to be able to handle the sorting of features based on an attribute to be a bit more user friendly. It currently requires the user to set three different values in three different areas to work. This will be consolidated into a single area.
I will probably build a separate form that can be used to better control the symbology of the features. Users will have an easier time selecting point symbols, and will have greater control over setting the colors for lines and polygons.
I have added a centroid function that creates a ‘center-point’ for polygons. This can be used for labeling.
I am adding better instructions on how to make sure that the shapefile is projected properly.
Users will also be able to only export a subset of the features in the feature class (such as only those in the current view, or those that have been selected).
Users will be able to export the view as a PNG overlay image.
I am also doing some experimenting with collada models. In some cases, lifelike models can be used to represent the features from the shapefile. This can be used in conjunction with the new features found in KML 2.1 to display features at different distances as different symbols (a generic circle at a great distance would be displayed as a model when the user gets close enough to see the model appropriately).
Thursday, July 06, 2006
Shape2Earth Instructions
Shape2Earth is a quick and easy way to convert GIS files into Keyhole Markup Language for viewing in Google Earth.
Instructions on how to use Shape2Earth Version 1.0 have been posted at this Shape2Earth Users Blog.
Instructions on how to use Shape2Earth Version 1.0 have been posted at this Shape2Earth Users Blog.
Monday, June 26, 2006
Advanced Touring in Google Earth
Way back when I first started investigating using Google Earth as a near real-time visualization client for a GIS, I stumbled upon GE’s very small API. For those of you not familiar with the term, an API is the Application Programming Interface for an application. It provides programmatic control to certain parts of the program.
The API for Google Earth is very small and experimental. The GE engineers did not make it publicly known, and do not support it (I am somewhat inclined to believe that that might change in the future). One of the things you can do is tell GE where to move to and how fast to move there. You can also tell it to load a kml file. I used these two very simple commands to create long running tours. You can really make some neat things happen when you have GE slowly spiral in and then quickly change directions. Coupling this with the dynamic loading and unloading of data makes for some really powerful visual presentations. These original tours were hard coded, and were begging for some automation.
To create the tours, I had built a small application that would capture the Latitude, Longitude, Range, Tilt, and Azimuth of my current view in GE. I could then paste the data into my move function in the Tour applications.
Over time, I have changed things quite a bit so that I can persist the views in XML. I can also set the movement speed and movement hold time using the user interface to get better movement effects, and then jump back and forth between each view to see how the overall movement looks.
Once a tour has been made, it can be saved as XML and used by others (assuming they have the same program). Eventually, I should be able to set it up so that people can quickly create their own fly-throughs and data loading sequences to demonstrate and or brief.
Some examples of how this can be used is as an education briefing (fly around to different geological areas of interest and load data to both highlight the area display text to describe it), operational briefings (Air Force pilots can be taken through a mission with data popping into view and described as required), engineering (this has already been used to tour through large scale engineering, construction, and logistics phases).
The uses are nearly endless.
The API for Google Earth is very small and experimental. The GE engineers did not make it publicly known, and do not support it (I am somewhat inclined to believe that that might change in the future). One of the things you can do is tell GE where to move to and how fast to move there. You can also tell it to load a kml file. I used these two very simple commands to create long running tours. You can really make some neat things happen when you have GE slowly spiral in and then quickly change directions. Coupling this with the dynamic loading and unloading of data makes for some really powerful visual presentations. These original tours were hard coded, and were begging for some automation.
To create the tours, I had built a small application that would capture the Latitude, Longitude, Range, Tilt, and Azimuth of my current view in GE. I could then paste the data into my move function in the Tour applications.
Over time, I have changed things quite a bit so that I can persist the views in XML. I can also set the movement speed and movement hold time using the user interface to get better movement effects, and then jump back and forth between each view to see how the overall movement looks.
I have also written a little utility so that you can export the tour as point placemarks in Google Earth. These placemarks keep the name and description information (viewed in the information balloon), and lets the application act as a very quick way to set placemarks defining features found in GE.
Once a tour has been made, it can be saved as XML and used by others (assuming they have the same program). Eventually, I should be able to set it up so that people can quickly create their own fly-throughs and data loading sequences to demonstrate and or brief.
Some examples of how this can be used is as an education briefing (fly around to different geological areas of interest and load data to both highlight the area display text to describe it), operational briefings (Air Force pilots can be taken through a mission with data popping into view and described as required), engineering (this has already been used to tour through large scale engineering, construction, and logistics phases).
The uses are nearly endless.
Sunday, June 18, 2006
Google Earth -- World Wind -- ArcExplorer
I was recently at an Air Force conference where Google Earth, NASA’s World Wind, and ESRI’s ArcExplorer where prominently displayed. The serious interest that organizations like the Air Force are putting into these platforms has given me the opportunity to explore each of these platforms a bit more in depth.
I am still using Google Earth a great deal. I don’t believe that it can currently be challenged in its ease of use and clean navigation. My 5 year old loves to play with Google Earth, and has no trouble getting around the planet to points of interest. Their KML data representation and the use of Network links to serve data offer a very interesting and open way to create very unique customizations. For organizations with a very large amount of data, it is tough to beat their server products. This would work very well for the Air Force, which could leverage their own imagery holdings with other services and NGA to create their own world for Air Force specific applications and visualizations.
Things I wish they would do …. Currently, Google Earth offers a couple of methods to integrate existing GIS data into their system. You can load KML files, or you can purchase their Fusion product that compiles your data into a format that can be hosted by their Earth Server product into a Google Earth Enterprise Client (the Google Earth Browser with extended features). You have two options with the Earth Server. You can either have a hybrid system in which you load your vector data into the Earth Server and view it against the Keyhole server imagery. Or you can get Enterprise Pro, and host ALL of the data in your own world.
The whole Google Earth product line is really an enterprise system. It works best when everything is put together. I would like to see what I would term an organizational level system (as opposed to enterprise). An example would be using a Windows 2003 Server to host organizational data (to include imagery) that can be securely fused with the larger Keyhole imagery server. The great majority of organizations don’t want to just load their vector data in the big Linux based Google Earth Server in a hybrid mode, or be responsible for populating an entire world if they have localized imagery. They want to view their holdings fused against the Google data.
Secondly, if the Google Earth Client could expose some additional capabilities to developers in their API, the GIS community could rapidly start tacking on some pretty sophisticated geoprocessing capabilities.
I finally got around to downloading the World Wind source code, and started investigating their method for creating Plugins. I have seen World Wind improve quite a bit over the last year. And believe that it will continue to get better. Its unique power in this game is that it is open source and license free. They automatically provide the ability to completely customize the user interface and provide the ability for any developer to integrate any type of GIS data. I am currently working on an extension that uses Yahoos geocoding service to search for locations and zoom to them in WW.
I have only seen ESRI’s ArcExplorer in Beta. I will withhold my comments on it until it is released. It will probably work very well for anyone who already has an investment in an ESRI based system. I am looking forward to doing some development work with it before the end of the year.
I am still using Google Earth a great deal. I don’t believe that it can currently be challenged in its ease of use and clean navigation. My 5 year old loves to play with Google Earth, and has no trouble getting around the planet to points of interest. Their KML data representation and the use of Network links to serve data offer a very interesting and open way to create very unique customizations. For organizations with a very large amount of data, it is tough to beat their server products. This would work very well for the Air Force, which could leverage their own imagery holdings with other services and NGA to create their own world for Air Force specific applications and visualizations.
Things I wish they would do …. Currently, Google Earth offers a couple of methods to integrate existing GIS data into their system. You can load KML files, or you can purchase their Fusion product that compiles your data into a format that can be hosted by their Earth Server product into a Google Earth Enterprise Client (the Google Earth Browser with extended features). You have two options with the Earth Server. You can either have a hybrid system in which you load your vector data into the Earth Server and view it against the Keyhole server imagery. Or you can get Enterprise Pro, and host ALL of the data in your own world.
The whole Google Earth product line is really an enterprise system. It works best when everything is put together. I would like to see what I would term an organizational level system (as opposed to enterprise). An example would be using a Windows 2003 Server to host organizational data (to include imagery) that can be securely fused with the larger Keyhole imagery server. The great majority of organizations don’t want to just load their vector data in the big Linux based Google Earth Server in a hybrid mode, or be responsible for populating an entire world if they have localized imagery. They want to view their holdings fused against the Google data.
Secondly, if the Google Earth Client could expose some additional capabilities to developers in their API, the GIS community could rapidly start tacking on some pretty sophisticated geoprocessing capabilities.
I finally got around to downloading the World Wind source code, and started investigating their method for creating Plugins. I have seen World Wind improve quite a bit over the last year. And believe that it will continue to get better. Its unique power in this game is that it is open source and license free. They automatically provide the ability to completely customize the user interface and provide the ability for any developer to integrate any type of GIS data. I am currently working on an extension that uses Yahoos geocoding service to search for locations and zoom to them in WW.
I have only seen ESRI’s ArcExplorer in Beta. I will withhold my comments on it until it is released. It will probably work very well for anyone who already has an investment in an ESRI based system. I am looking forward to doing some development work with it before the end of the year.
Thursday, June 01, 2006
Download Shape2Earth Beta 2
UPDATE: Shape2Earth Beta 2 testing has closed. Shape2Earth Version 1.0 hase been released as shareware, and is available for download below.
http://shape2earth.com
http://shape2earth.com
Sunday, May 14, 2006
Shape2Earth Beta 2 Testing
[Note: Shape2Earth Version 1.0 has been released as shareware and is available for downloading and evaluating at http://shape2earth.com. The evaluation period described below has resulted in dramatic enhancements to Shape2Earth.]
------------------------------------------------------------------------------------------
A couple of people have taken the time to look at and test Shape2Earth Beta 2. The Beta 2 application has a number of enhancements over the initial test release. There are a couple of consistent requests between the two releases that I will begin to work on shortly.
While feedback has been very positive overall, a couple of issues I have received so far deal with the install package and shapefiles behaving badly. I’ll need to implement a better error handling system so that people will know if the problem is with the shapefile or with Shape2Earth.
Wider use has helped to weed out issues. With that in mind, I would like to invite anyone who is interested in testing Shape2Earth Beta 2 to please send a request to me at Sabin21@gmail.com.
For those interested, I would recommend downloading and installing MapWindow GIS before requesting to test Shape2Earth Beta 2.
As I compile feedback and start adding improvements for Beta 3, I will start to send out a more format questionnaire to beta testing participants.
------------------------------------------------------------------------------------------
A couple of people have taken the time to look at and test Shape2Earth Beta 2. The Beta 2 application has a number of enhancements over the initial test release. There are a couple of consistent requests between the two releases that I will begin to work on shortly.
While feedback has been very positive overall, a couple of issues I have received so far deal with the install package and shapefiles behaving badly. I’ll need to implement a better error handling system so that people will know if the problem is with the shapefile or with Shape2Earth.
Wider use has helped to weed out issues. With that in mind, I would like to invite anyone who is interested in testing Shape2Earth Beta 2 to please send a request to me at Sabin21@gmail.com.
For those interested, I would recommend downloading and installing MapWindow GIS before requesting to test Shape2Earth Beta 2.
As I compile feedback and start adding improvements for Beta 3, I will start to send out a more format questionnaire to beta testing participants.
Monday, April 17, 2006
Shape2Earth Beta 2
[NOTE: Shape2Earth Version 1.0 has been released for download at http://shape2earth.com]
There are a number of nice enhancements added to Shape2Earth for the Beta 2 release.
Optimized Speed
Shape2Earth has been optimized and is much faster when writing KML.
Query Attribute Data
Users can query GIS attribute data using keyword inputs, can sort fields, and can zoom to selected features in Google Earth. This is very helpful for large datasets, and for polygons that are not selectable in Google Earth.
On-The-Fly Reprojecting
Users no longer have to reproject their data to WGS84 before converting. Shape2Earth can now re-project on the fly from the original projection to Google Earth’s projection.
Enhanced Point Options
Users have a better selection on which graphics to use to represent point features. They also have the option of changing the size and color of a point when the mouse hovers over it in Google Earth. Similarly, users can set up the KML so that the attribute used to name the feature is only visible when the point is hovered over (see below).
Improved Interface
The Shape2Earth interface has been compacted, with tools being moved from the Form to a toolbar on the top. This helps when people want to interact with Shape2Earth and Google Earth at the same time. The ability to keep the Shape2Earth Form on top of Google Earth all of the time has been added to the options menu.
There are a number of nice enhancements added to Shape2Earth for the Beta 2 release.
Optimized Speed
Shape2Earth has been optimized and is much faster when writing KML.
Query Attribute Data
Users can query GIS attribute data using keyword inputs, can sort fields, and can zoom to selected features in Google Earth. This is very helpful for large datasets, and for polygons that are not selectable in Google Earth.
On-The-Fly Reprojecting
Users no longer have to reproject their data to WGS84 before converting. Shape2Earth can now re-project on the fly from the original projection to Google Earth’s projection.
Enhanced Point Options
Users have a better selection on which graphics to use to represent point features. They also have the option of changing the size and color of a point when the mouse hovers over it in Google Earth. Similarly, users can set up the KML so that the attribute used to name the feature is only visible when the point is hovered over (see below).
Improved Interface
The Shape2Earth interface has been compacted, with tools being moved from the Form to a toolbar on the top. This helps when people want to interact with Shape2Earth and Google Earth at the same time. The ability to keep the Shape2Earth Form on top of Google Earth all of the time has been added to the options menu.
Saturday, April 01, 2006
Querying GIS Data in Google Earth
Feedback has been coming in from people who have been kind enough to test Shape2Earth Beta 1. So far, I have been quite pleased with the results. There do not appear to be any major glitches. I'm still open for more people to try it out if they would like.
Someone pointed out that it would be nice to be able to alphabetically sort the features in KML so that people could more easily find them in Google Earth. This is a great idea, and I’ll be looking into a sorting method soon. In the meantime, I started investigating how to query the data in a manner similar to the way that we query GIS data. The basic idea is to query and/or sort features in Shape2Earth using their attributes, and then zoom to their location in Google Earth.
To do this, I have added an additional tab to the Shape2Earth form. It loads all of the attribute data of the shapefile into a data grid. Data is only loaded when requested in order to optimize performance for users who only want to convert data to KML.
Someone pointed out that it would be nice to be able to alphabetically sort the features in KML so that people could more easily find them in Google Earth. This is a great idea, and I’ll be looking into a sorting method soon. In the meantime, I started investigating how to query the data in a manner similar to the way that we query GIS data. The basic idea is to query and/or sort features in Shape2Earth using their attributes, and then zoom to their location in Google Earth.
To do this, I have added an additional tab to the Shape2Earth form. It loads all of the attribute data of the shapefile into a data grid. Data is only loaded when requested in order to optimize performance for users who only want to convert data to KML.
Once selected, all of the attributes are loaded into the table. In this example, I have already loaded a shapefile of world volcanoes into Google Earth as a KML network link. Each feature in the table of contents in Google Earth has the name of the volcano, but they are not in alphabetical order.
With the attribute data from the KMLs companion shapefile loaded into Shape2Earth, I have a couple of options for finding a particular feature. I can sort the table based on any of the fields (see below) and then manually select the feature in the table that I would like to zoom to in Google Earth.
I can also search for attributes using a text field to enter values. I can look for specific values, or use a 'like' clause to match close values. In this example, I have entered 'helens' to query for Mount Saint Helens. I have one record that matches this query, and I can view it by itself by clicking 'View Selected'.
I can return to the rest of the table by clicking "Shop All". To zoom to my selected feature, I simple click on "Zoom to Selected", and then watch as Google Earth gracefully zooms to the item I have selected.
To make this querying capability as fluid and useful as possible, I have added an option that allows for Shape2Earth to always sit on top of Google Earth. This provides the ability to really smoothly navigate through Google Earth usinattributeribute data.
So far, it has worked fantastically for points and polygons the size of buildings. I'll have to add some geometric functions for it to work appropriately for large polygons. GE does not let you set the MapView coordinates that way that a typical GIS does. So I will need to mimic this using a center-point and distance.
Friday, March 24, 2006
Importing Shapefiles into Google Earth
[Note: The methods described below can now be done entirely within Google Earth. Refer to Using Google Earth as a GIS form more information. For translating shapefiles to KML, Shape2Earth Version 1.0 has been released as shareware.]
The image (show above) of Keyhole Markup Language (KML) data in Google Earth was created entirely with shapefiles and GIS software that is freely available over the Internet. OpenJUMP was used to create the buffer around a school. MapWindow GIS was used to apply the symbology. Shape2Earth (which works as a plug-in for MapWindow) was used to convert the shapefile to KML, which was then loaded in Google Earth for visualization.
Above: OpenJUMP (open source GIS written in Java) is used to create a buffer around the selected building.
Above: The buildings and buffer shapefile are loaded into MapWindow GIS (open source GIS written in .NET). Symbology is applied, and Shape2Earth is used to convert the shapefile and symbology into KML.
Now that Shape2Earth is in beta testing, I have had the opportunity to get some great feedback on its functionality, and have seen some REALLY cool KMLs created by a number of people througout the world.
The image (show above) of Keyhole Markup Language (KML) data in Google Earth was created entirely with shapefiles and GIS software that is freely available over the Internet. OpenJUMP was used to create the buffer around a school. MapWindow GIS was used to apply the symbology. Shape2Earth (which works as a plug-in for MapWindow) was used to convert the shapefile to KML, which was then loaded in Google Earth for visualization.
Above: OpenJUMP (open source GIS written in Java) is used to create a buffer around the selected building.
Above: The buildings and buffer shapefile are loaded into MapWindow GIS (open source GIS written in .NET). Symbology is applied, and Shape2Earth is used to convert the shapefile and symbology into KML.Now that Shape2Earth is in beta testing, I have had the opportunity to get some great feedback on its functionality, and have seen some REALLY cool KMLs created by a number of people througout the world.
Saturday, March 18, 2006
Shape2Earth Beta Nearing Release
I think that the Shape2Earth shapefile to KML coverter for Google Earth is just about ready to be released to a number of beta testing volunteers. I was debating whether or not I should spend some additional time optimizing certian sections of code. I'm leaning more towards just getting it out there. I'm not going to worry so much about making it able to run just a little bit faster. There is more than enough functionality available now to make it well worth looking at. I 'm really excited about getting feed back to see what I should focus on next.
Subscribe to:
Posts (Atom)