Description

• LatLon_tiling is a way to increase the resolution of a shape model similar to Basic_tiling. The major difference between the two is that Basic_tiling increases the resolution of the shape model one bigmap at a time while LatLon_tiling increases the resolution of the shape model all at once by placing maplets at selected latitude and longitude locations.

• The key advantage of LatLon_tiling is that it is faster than Basic_tiling because bigmaps don't have to be created. However, when the resolution needs to be high (below 75 centimeters) a much larger amount of maplets/landmarks need to be created at various coordinates than when the resolution is lower. A large amount of maplets have to be made when doing LatLon_tiling at high resolution because the maplets get smaller as resolution increases and the maplets have to cover the entire surface of the shape model along with overlap. The larger amount of maplets will make LatLon_tiling difficult to manage.

• An example of LatLon_tiling being difficult to manage is when it is done at a high resolution, which leads to thousands of maplets/landmarks being produced. When find_nofitT is used to look at the bad landmarks, hundreds if not thousands of errors may pop up. All of those bad landmarks will have to be fixed using Lithos and that sucks. When Basic_tiling is used and regions of the shape model are tiled into bigmaps instead of the entire shape model, then each bigmap will be composed of only hundreds of landmarks, which will most likely have a a lot less misaligned landmarks.

• Thus, it is best to use Basic_tiling at higher resolutions because then the various maplets used to create topography are done by region (bigmaps), which leads to better organization. Furthermore, each bigmap will have a lot less bad landmarks than the entire shape model when LatLon tiling is performed, which leads to less landmark clean up for the individual when work for Basic_tiling is distributed by region among others.

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LatLon_tiling Steps

Step1

Prep

You need two files:

• make_scriptT.in - this contains three things

  • Reference system (either a bigmap or the string "LATLON" to define landmarks)

  • The filename of the SEED file, the file that has the lithos commands we will use to create the landmarks. You can include a path.
  • A list of the locations, and in this case it is the Latitude/Longitude (West Longitude)

  • The latitude and longitude spacing in make_scriptT.in file has to be determined based on the resolution being tiled so that the maplets overlap. Tanner Campbell has created make_scriptT.in LatLon files for various resolutions.

• Seed file. Frequently stored in the SCRIPTS directory. Make sure whatever this file's name is matches the one in the make_scriptT.in file.

  • Seed file name should correlate to the resolution of the maplets to be made. For example, XXX150.SEED makes maples at 150 cm resolution

make_scriptT.in should look like this:

LATLON
SCRIPTS/XXX150.SEED
 00,    000
 00,    012
 00,    024
 00,    036
 00,    048
 00,    060
 00,    072
 00,    084
 ....
-84,    315
 90,    000
-90,    000
END

• LATLON tells the program that latitude and longitudes are to be entered
• SCRIPTS/XX1500.SEED calls the seed file
• The following list of longitudes and Latitudes are where the landmarks are to placed.

The seed file should look something like this:

0.00150,49
g
i
a
y
.5
n
x
.025
0
a
m
n
2
m
u
1
v
2

Run

~/bin/make_scriptT

For the above command to work a make_scriptT.in file must be in the directory you are working in.

Output

• INN files (1 to 361)
• rem_script.b
• run_script.b
• dsp_list.txt

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Step 2

Run

Run, just run the script to make the whole thing go (in the background)

nohup sh run_script.b &

Monitor

Track the progress with find_nofitT

~/bin/find_nofitT

If there are problems with the processing, you'll get a list of landmarks with issues

  just listed - no significant issue
  * very bad - must fix
  ! not too bad - should fix