docs:autocad:map:projection_and_shp_file_example

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docs:autocad:map:projection_and_shp_file_example [2007/04/21 00:44] – billhdocs:autocad:map:projection_and_shp_file_example [2008/08/03 00:25] (current) – external edit 127.0.0.1
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 +====== Autodesk Map: Projection and SHP file example ======
 +
 +===== Prerequisites =====
 +
 +  * Autodesk Land Desktop 3 (the version used for this example, but other versions should work)
 +  * State Boundaries shape file (statesp020, in the "Boundaries" section)
 +    * http://nationalatlas.gov/atlasftp.html
 +
 +===== Initial Procedure =====
 +
 +  - open Autodesk Map (not Land Desktop - it is not required)
 +  - Map -> Tools -> Assign Global Coordinate System
 +  - click "Select Coordinate System"
 +  - under "Category", select "World/Continental"
 +  - under "Coordinate Systems in Category", select "Lambert Conformal Conic projection for North America, Meter"
 +  - click OK twice, to close both dialog windows
 +  - Map -> Tools -> Import
 +  - set the "Import Type" to "ESRI Shape"
 +  - use the Drives and Folders sections to locate your states shapefiles folder (your files will not yet be visible)
 +  - click OK
 +  - make sure only one the statesp020 shapefile is checked
 +  - in the statesp020 row, in the "Input Coordinates" column, click once to highlight the cell and then click the three dots at the right side of the cell to open a dialog
 +  - select "Lat Longs" for the Category, and select the first option "No Datum, Latitude-Longitude, Degrees -180 to +180", and click OK (note that you must click something for this to work, even if what you want was already selected when the dialog first appeared)
 +  - you should now see the letters "LL" in the Input Coordinates column
 +  - verify that "Perform coordinate conversions" is checked in the Format Options section
 +  - click OK to begin the import process
 +  - after the import is finished, zoom to extents (Z <space>, E <space>)
 +  - you should now see the 50 states, with a common projection shape (the north border of the continental U.S. should be curved)
 +
 +===== Working with Lat/Long Coordinates After Importing Data =====
 +
 +  - notice that when you move your cursor, your coordinates are large numbers (these are meters from approximately the center of the U.S.)
 +  - to move your cursor and see Latitude/Longitude:
 +    - go to Map -> Tools -> Track Coordinates
 +    - click the "Select coordinate system" button (the earth with an arrow)
 +    - select "Lat Longs" for the Category, and select the first option "No Datum, Latitude-Longitude, Degrees -180 to +180" and click OK
 +    - notice that your Autocad coordinate display (lower right of Autocad window) will show the meter coordinates of your original projection, but the Track Coordinates dialog will show Latitude/Longitude coordinates as you move your cursor
 +  - to use a command, such as drawing a point at a specified Lat/Long (such as a point you have on a hand held GPS unit, or something you have on another map):
 +    - first start by entering your desired command, such as "point <space>" (for drawing a point)
 +    - use the X and Y fields in the "Track Coordinates" dialog to type in the Latitude and Longitude of your desired point
 +    - click the "Digitize" button in the "Track Coordinates" dialog (pen with a cross)
 +    - you should see the calculated coordinates appear in the command line (where your point command was waiting for input)
 +    - a point should be created at your desired location
 +