Unofficial FAQ

World Wind Faq v 0.4
Compiled and Maintained by Llynix
Contributors:
Llynix (Anthony Taylor)- llynix [Funky At Sign] gmail.com
Chris Maxwell (lead developer)
Various forum posters (if you want credit please let me know)
Recommended Specifications
* Windows 2000, XP Home, or XP Professional (Does not work on Windows ME)
* Intel Pentium 3 1 ghz or AMD Athlon or higher
* 256 MB of RAM
* 3D Graphics Card
o nVidia GeForce 2 Ultra
o ATI Radeon 7500
o Intel Extreme Graphics 2
o Check out the Video hardware compatibility list.
* DSL / Cable connection or faster
* 2 GB of disk space

World Wind Notes

World Wind benefits most from a video card with 3d acceleration. If you don't know your machine comes with one, it is likely to have one built in if the machine was purchased within the past two years.

World Wind requires DirectX 9b (DirectX 9c works as well) and the .NET Runtime environment to be installed. These have been included in the World Wind installer

World Wind comes with a certain amount of data you can zoom into. After a certain point, World Wind will begin to download more images automatically. At this point, your Internet connection can make a big difference.
Bandwidth and Server Isuues
Why can't I download the program? Why is it so slow?

On Sep 24th, 2004 the program was listed on slashdot, a very large news site. As a result there have been severe bandwidth issues in both obtaining the program and downloading data sets while using it. Data sets are slow to download. Cached files are slow to check so they aren't used. Hopefully in a few days the crisis will pass. In addition later version will surely include optimizations of the network code to prevent further issues. And additional bandwidth may be added to the project. Try the program a couple of days from now and see if the issues still remain.

Update:

As of Sep 26, 1:47 AM (CST) The USGS server was working fine. However the Landsat 7 server seemed to be out.

For international users is means it doesn't look like anything is loading. Try playing around with the animated earth and other features.

Chris offers this tweak:

The reason USGS is slow is because it still tries to take elevation from JPL. If you modify your worldLayers.xml file under the "Configuration" directory, you can set the USGS Layers "Terrain Mappped" elements to "false" and it will not access JPL anymore and in theory, load USGS much faster since the MS server is much healthier right now than the JPL server.

Again, it won't be terrain mapped, but you at least get *something* until the JPL server can catch up to everyone's requests.

Is there a cache? Why isn't it working?

There is a cache located at: c:\Program Files\NASA\World Wind v1.2\cache

The program will cache up to 2 gb of data. After this it will delete data based on usage (least used gets deleted first)

Chris:

... Due to the elevation loading scheme and server load, it is having problems loading in cached areas. This relates to the downloading of an image tile, but a failed attempt to download an elevation tile, and this issue will be addressed in an upcoming version.

Why are the wrong image tiles showing up?

Possbily and probably due to the server bandwidth issues.

A work-around is to delete the numbered folders in the "cache" directory, but then of course you have to re-download all the images then next time you run the program. It's not obvious which particular cache files correspond to the "bad" areas.

You can also use a DDS viewer to browse and delete the offending files.

Nvidia's DDS viewer -- http://developer.nvidia.com/object/n...ure_tools.html
- By installing this you can switch to thumbnail view in the explorer and find and delete those nasty tiles.

Another good .dds format reader is Irfanview -- http://www.irfanview.com/

Can I use this for international locations?

The USGS data is only available for US users. However the landsat 7 data is available globally and you can pick out many prominent features in your location. Work is in progress for additional data sets.

Is there a bittorrent up?

Yes. There are bittorrents up. However none are official from Nasa due to administrative issues. This forum discussion has links to torrents.

http://learn.arc.nasa.gov/worldwind/forums...hp?showtopic=45

How about bittorrent for the data sets?

Chris:

We have had others suggest to take a bit torrent approach to data delivery, and it would definitely be complicated to develop, but we are looking into it.
How large is the data set? Is it available for download?

The data set is ~ 20 Terabytes. As such it is not available for localized download.
Tips
How do I know it's downloading data?

Chris:

The NASA logo means that you are downloading imagery (attempting anyways). However, for the TerraServer (USGS) stuff, there is no icon for that, and you should just get the red box.

My video card isn't working?

Chris:

Voodoo3 definitely won't work. It's got a max texture size of 256x256, and the textures we use are well, bigger...

Check out the Video hardware compatibility list.

How can I extract data from Worldwind for use in other modeling and mapping applications?

Chris:

All the data is cached in the installation folder under the "Cache" directory. It's organized by the dataset, however, images are in DDS compressed format so you would need photoshop with the DDS plugin (or something similar) to convert the images back to a standard image format.

However, I think the source jpg MODIS images are cached and not deleted.
How do I load the .25 meter resolution maps, as shown in the screenshot of D.C. on this web site?

Chris:

That is actually only accessible under the Layer Manager->Images->High Resolution Terrain Mapped->USGS Urban Area

Enable that tree node and disable any other ones that are enabled in that particular list

What is the most proportionate "vertical exaggeration"?

Chris:

Although it seems that 2 or 3 should be the "correct" vertical exaggeration, "1" is the correct and real vertical exaggeration. More correctly, "1" means that the vertical height is multiplied by 1.0, whereas vertical exaggeration of 3 means that vertical height is multiplied by 3.0.

When I run setup.exe I get this error.

1608: Unable to create InstallDriver instance.
Return code -2147024894

Running the ISScript8.msi may bypass this.

Please see : http://consumer.installshield.com/kb.asp?id=Q108440
Future Versions
Is there a way to set a proxy?

Chris:

We recently recognized the need for this and it seems this issue is more common than we had planned. We will bump this feature to a high priority. We don't want to see people unable to experience all the excellent features in World Wind. Look for this in our next update.

Do you think you could add boundaries of other sub-national entities, such as Swiss cantons, Australian states, and Canadian provinces and territories?

Chris : It's coming.

Why is Internet Explorer loaded even though it is not my default browser?

At this time the program is hardcoded to load IExplore.exe. Hopefully later versions will remedy this.

This link may help developers. http://support.microsoft.com/default.aspx?...kb;EN-US;305703

Any chance a future version could make the amount of cache adjustable?

Chris:

Yes, the next version will make this freely adjustable to whatever the user desires.

Is there a way to narrow down a search for a place?

Chris:

We realized this problem almost immediately (there are approximately 2 million places with 3 million more about to be imported) and we're going to associate a "Place" with a country or geographic identity. Perhaps you will type in "Paris France" and you will only get matches that have those two keywords. Also, if anyone hasn't noticed, the searching tool is case sensitive, and that will of course be changed as well.

In addition, we want to display more meta-data information about a particular place, such as the type of place(mountain, populated place, beach...), and perhaps attributes such as population or elevation. We of course are open to suggestions that anyone else might have in terms of what would be useful.

There are place names all over the place!

Chris:

Yes, the amount of placenames is a bit of a nuissance, and we're working on ways to remedy this problem. We still want those placenames in there, we just don't want them to take up so much real estate on the screen.

-- Side note,if you go to the layer manager (tools / layer manager) under placenames you can click off certain ones. It may be helpful to remove the one labeled "US Anthropogenic Features" which contains info about churches, schools and other landmarks in the US.

**bug?** Some placenames are duplicated. For example, Bonham Elementary School and Bonham School, Lamar School and Lamar Elementary School, Alamo School and Alamo Elementary School, Statue of Liberty National Monument and Statue of Liberty (all in nearly same place). Is it useful to report these? There seem to be a bunch.

The entire time the application is running, it uses 50-100% of the CPU, why?

World Wind uses the similar technologies to most high-end video games, and as such, requires a large percentage of the CPU. This will get optimized in future releases, but we're still heavily in the Research & Development stage.

How about other planets?

Chris:

We actually already have plans to use NASA World Wind for the Mars data sets as well.

I would love to see a feature that showed day/night in realtime say taken from the USNO atomic clock. Perhaps a setting where you could follow the terminator and such.

It's on our list, slightly more elevated now that you asked for it.
Developers
What license are you releasing under?

Nasa Open Source license v1.3.

Will World Wind remain always free?

Chris:

The program itself is open-source and will always be free. Access to NASA provided data will also remain free. However, there might be private companies that want to provide their data through World Wind (perhaps magazines or encyclopedias) and perhaps might charge a fee for access to their data. As long as there are people who want NASA provided data, and are using World Wind for that purpose, it gives the departments in charge of providing data a reason to ask for more funding to improve bandwidth to the data.

Why did you decide on C# and Direct X?

See this forum posting: http://learn.arc.nasa.gov/worldwind/forums...w=findpost&p=17

Mac and linux ports?

I'm the lead and (so far) only programmer behind the NASA World Wind project. I've mentioned elsewhere in the forum some of the reasons for using Microsoft based-technologies, but the basic reason is that given our extremely limited budget and resources for this educational software tool, using C# and Managed DirectX was the only way to get a deliverable out to the public in short order. We want a Linux and especially an OSX port for World Wind, and this will happen sooner rather than later. However, we are still trying to finalize certain features and functionality that are best done using our current development suite, but we want World Wind to be ported to other operating systems and we are actively seeking partnerships to accomplish this goal.

Since this is open-source, we encourage any OSX programmers to start a port and we will try our best to provide whatever resources we can towards the effort. Right now our development staff consists of one programmer and one graphics designer, but we are an ambitious duo so we will do our very best to please everyone.
Links
Places for high res images:

Blue Marble - http://earthobservatory.nasa.gov/Newsroom/BlueMarble/
Planetary Photojournal at JPL - http://photojournal.jpl.nasa.gov/index.html
NRL Monterey Marine Meteorology Division - http://www.nrlmry.navy.mil/tc_pages/tc_home.html

These programs are similar / related to World wind.

Celestia - http://www.shatters.net/celestia/

Keyhole - http://www.keyhole.com

[post=]Quoted post[/post]

[cmaxwell]

Wow, nice FAQ. I'm editting the entry about caching if you don't mind.

[Llynix]

Originally posted by cmaxwell@Sep 25 2004, 04:51 PM
Wow, nice FAQ. I'm editting the entry about caching if you don't mind.

Quoted post

No problem, your the boss

Probably later tonight I'm going to restructure it so it's a little more readable. As of now all I did was cut and paste and add a few comments / paraphrased here and there.

Llynix

[Jugalator]

Just some minor feedback to this nice FAQ -- it would be nice if the questions were bolded with [b] tags or colors.
Gets kind of tough to look something up for me at least.

But maybe that's part of your "readable" restructuring plans, hehe.

[Randy Kim]

OOOoooo, nice FAQ. When things settle down, could I ask to use it on our website?
-Randy

[Llynix]

http://learn.arc.nasa.gov/worldwind/forums...p?showtopic=148

[Llynix]

Originally posted by Randy Kim@Sep 25 2004, 05:34 PM
OOOoooo, nice FAQ. When things settle down, could I ask to use it on our website?
-Randy

Quoted post

Feel free. I tried to post it in the FAQ forum but found I couldn't. Anyway you could give me access there?

Made some minor changes, added the bold tags, ran a spell check. If anyone has any questions / answers they would like to see please post it here or email me.

I'll be working on it some more.

Llynix

[Henk Poley]

Llynix could you just update the post at the top? That would make a smaller topic / thread.

[Llynix]

http://learn.arc.nasa.gov/worldwind/forums...p?showtopic=148

[Nick S.]

It would be worth adding some questions about computer specs - the recommended (already available) and the minimum (not so readily available).