Terrain Data
DEM
Digital Elevation Model
One thing you have to get in count its this:
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For analysis obstacles AirNavCAD use DEM Digital Elevation Model.
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This is a grid with altitudes and the file is asc type; Only the bounds are drawing on workspace.
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But also can draw terrain on workspace with shp files, with contour lines, points and populations.
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Load shp files
In AirNavCAD you can load shape files.
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In Spain we get that information from www.ign.es
it's a public service.
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We know you can find these files in other sources.
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You can load also dxf but shape file is better for the performance.
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Load shp files
You have to create a folder normally the data is given in a rar file so you have to unzip in a folder.
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If you want to load that data simply select that folder.
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The folder data is composed of the following data, the most important are curv_line, pun_aco and pob for population. It depends on your country the name could be different but don't worry.
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Also is possible to select several folders to load and also select only one shp file to load.
Load Shp files
other sources
If you load data for another source you must accomplish the following if user want load the 3 types at same time:
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CUR_NIV_line for terrains contour lines add
PUN_ACO_point for points ENT_POB for populations
or simply put only 4 files in the folder forgetting about names.
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Some times of altitude of the feature depends on one parameter name from your source, it could be implemented easy if not load correctly the z elevation.
Draw on workspace
You have to go to:
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BasicOperations/
Draw shp ign format or
Draw shp other formats
OUTPUT
Select the folder in the folder system and wait to get the output End process.
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In this case you can load 200 MB of data without problems. The limit is not heap the memory of the program that is 4GB.
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By default only pop is active. You have to make the other layer visible.
OUTPUT
If you activate the Shape layer you can see the terrain contour lines. Do zoom in or zoom out to see more details.
OUTPUT
zoom in, on the contour terrain lines, points and populations.
EYE Tool
The most important thing to load shp files is that you can apply the EYE tool and hide terrain below at an altitude you give. It helps check any critical obstacle you get.
EYE Tool
As you can see the eye tool hide the altitude you give.
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The Eye tool apply also for obstacles and any layer that contains "shape" on name of Layer.
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Be aware that the elements are on the workspace the only effect for applying eye tool is that you can not see it.Click default to recover view at finish.