Technical Reference - Elevation Data

Overview
Unlike many flight simulators, Tacview does not try to project a spherical terrain on a flat surface. It uses a true spherical earth instead. Like Google Earth, Tacview is able to display the earth in its whole like it is in real life!

The terrain of Tacview is made of layers. From the lowest resolution (ETOPO1) to the highest resolution (SRTM1), Tacview engine automatically displays the most appropriate level of detail depending on current zoom level and data available. For example: When a required hi-res SRTM1 tile is not available, Tacview tries to display the corresponding med-res SRTM3 tile. If no SRTM3 tile is available, it falls back on the default low-res ETOPO1 base map...

You can let Tacview automatically choose the most appropriate layer set according to the flight data source. Or you can force a specific layer set by using the appropriate option. Falcon 4 theaters are also natively supported, and new ones can be integrated in just a few minutes by adding a declaration in the appropriate .xml file. It is also very easy to download and install additional EECH and real-life terrains: Just have a look in the add-ons section!

Which data sources are natively supported by Tacview?

 * National Geophysical Data Center ETOPO1 worldwide base map (about 1.25 km resolution)
 * Shuttle Radar Topography Mission SRTM30 (about 750 m resolution)
 * Shuttle Radar Topography Mission SRTM3 (about 75 m resolution)
 * Shuttle Radar Topography Mission SRTM1 (about 25 m resolution)
 * Falcon 4.0 Theaters

Which terrains are included and displayed by default in Tacview?

 * ETOPO1 worldwide base map (Tacview Standard or above required)
 * DCS: Caucasus Map
 * DCS: Syria Map
 * DCS: The Channel Map
 * DCS: Persian Gulf Map
 * DCS: Normandy 1944 Map
 * DCS: NEVADA Test and Training Range Map
 * BMS: Korea
 * BMS: Balkans
 * BMS: Israel
 * BMS: Pillars of Hercules
 * BMS: Aegean
 * BMS: Ostsee
 * BMS: NTO Polar Vortex
 * BMS: Kurile Island
 * IL-2: Battle of Kuban
 * IL-2: Battle of Moscow
 * IL-2: Battle of Stalingrad
 * IL-2: Velikie Luki
 * IL-2: Rheinland
 * IL-2: Prokhorovka
 * IL-2: Arras

Which terrains are included in Tacview but disabled by default?
Because of the overlap between several Falcon 4.0 theaters, the following terrains are installed in a disabled state by default. You can easily enable these terrains by following the provided instructions. Do not forget to disable any conflicting theater to ensure proper telemetry and 3D view display.
 * BMS: East Mediterranean Front
 * BMS: Ikaros
 * BMS: Falcon Online RedFlag RP6
 * IL2: Lapino
 * IL2: Novosokolniki

What about other flight simulations? Where can I download any terrain for them?
You can find real-life and Microsoft Flight Simulator terrains in the add-ons section. If your favorite region is missing, you can easily add it yourself by following the instructions below. All EECH theaters are available in the add-ons section too and can be installed in just a few clicks! (See below for more information)

When zoomed-out, the earth globe is just made of water without land. Is this a bug?
The ETOPO1 worldwide base map is an exclusive feature of Tacview Standard and above. If you are using Tacview Starter, you may consider buying one of the improved editions of Tacview to enjoy the worldwide base map when not in high detail zones.

How can I import my own Falcon 4.0 terrain in Tacview?
You can easily activate any provided theater or add your own Falcon 4.0 theater to Tacview by following the provided instructions.

How can I add higher-resolution real-life SRTM1 and SRTM3 tiles to Tacview world?
Tacview natively supports SRTM1, SRTM3, and SRTM30 files and automatically fills invalid data (holes) using ETOPO1 data. All you have to do is to download the tiles of your choice, unpack the .zip archives and install the resulting .hgt files in the appropriate folder: When adding SRTM1 terrain to Tacview, is it also suggested adding the equivalent SRTM3 terrain to ensure nice transitions when zooming in and out. Because picture is worth a thousand words, you may want to have a look at a quick video tutorial available on YouTube.
 * SRTM1 files must be placed in  %ProgramData%\Tacview\Data\Terrain\SRTM1\ or %APPDATA%\Tacview\Data\Terrain\SRTM1\
 * SRTM3 files must be placed in  %ProgramData%\Tacview\Data\Terrain\SRTM3\ or %APPDATA%\Tacview\Data\Terrain\SRTM3\ \
 * SRTM30 .Bathymetry.srtm files must be placed in  %ProgramData%\Tacview\Data\Terrain\SRTM30\  or  %APPDATA%\Tacview\Data\Terrain\SRTM3\

Some SRTM tiles are full of holes despite the automatic filtering. How can I improve this?
Because of the radar technique used during Shuttle Radar Topography Mission, canyons and mountains can contain quite a lot of holes. Tacview is doing its best by filling holes using the available low-resolution ETOPO1 data. However this does not always give perfect results. This is why, you may want in some cases, to download pre-filtered data or to use a dedicated program to filter terrain data in a smarter way.

The first thing to do is to look for pre-filtered data on Jonathan de Ferranti's web site. These data are cleaned-up using topographic data coming from several alternate sources and usually gives great results.

If you can't find any pre-filtered data or you are not happy with the ones provided, you may want to try a filtering program such as Blackart. Even if this program is really awful to use, it gives impressive results! Here is the how to use Blackart:
 * Select  File | Batch Mode Interpolate | SRTM to SRTM
 * Add your SRTM files to the list
 * Press  [Continue]
 * Set  LSQR Iterations  to  100
 * Set  Laplacian Iterations  to  1000
 * Reset the  Scale Factor  to  1  (because the decimal separator may not be properly handled)
 * Click on  [Submit], accept the default  -32000  value for null data then  [Submit]
 * Select  Run | Run Blackart
 * Copy the resulting files in the appropriate Tacview folder and rename them from  .hgx  to  .hgt

How can I add my own custom elevation map?
Have your custom elevation map ready in RAW format.

Copy the file

C:\Program Files (x86)\Tacview\Data\Terrain\Custom\CustomHeightmapList.xml

to the folder

%ProgramData%\Tacview\Data\Terrain\Custom\

Open the file which is now in your Program Data folder. Following the instructions and examples in the file, add a new entry for your RAW file. Place your RAW file in the same folder. Re-launch Tacview.

How to display the proper EECH terrain in Tacview?
To reduce the installer size, EECH terrains are not included within Tacview by default. You need to download the EECH maps from the add-ons section. Unpack the ZIP file and copy the resulting  HGT  files in  %ProgramData%\Tacview\Data\Terrain\EECH\  or  %APPDATA%\Tacview\Data\Terrain\EECH\. Then, in Tacview, make sure that the terrain option is set to either Auto or EECH.