Movmap3D (Ver. 0.2)


  Movmap GPS program has now become Movmap3D! You can now load
 SRTM 90m elevation data and view your maps in 3D, right in
 your PocketPC. 90m or 3" SRTM elevation data for most regions 
 of world is freely available. Movmap3D supports SRTM 90m data 
 in .hgt format. The 30m SRTM data files are not supported as they
 are not yet available for all regions. At present, unfortunately,
 the SRTM data has many void regions or holes. This happens in
 surface regions where radar return signal from the Space Shuttle is
 too weak. 
 (SRTM files available at:
   ftp://e0srp01u.ecs.nasa.gov/srtm/version2/SRTM3/
  Details about SRTM mapping can be found in:    
www.geol.ucsb.edu/faculty/burbank/BurbankPDF/Farr%20et%20al%20SRTM%20RoG2007%20copy.pdf    
 )

 The SRTM data is in a simple and convenient format. Each 93m or 3" 
 SRTM .hgt file covers a surface of area 1deg x 1deg. For example,
 the data file name N12E080.hgt will contain 1201x1201 points of
 elevation data (in meters) from latitude 12 deg.N to 13 deg.N and
 longitude 80 deg.E to 81 deg.E. 

 You can select a small area (240x240) of your 2D map and view
 that area as a 3D image from various directions, eye angles
 and zoom levels. 3D Views from N, E, W and S directions are
 available. The program allows display using various 3D surface
 models: as rectangular planes in pseudo color, as rectangular 
 gray scale planes lit from eye direction, as wire-frame
 triangles in pseudo color or in gray scale, and as texture
 mapped surfaces. Simple orthographic projection is used for 3D
 display. 

  If no map image file or shapefile is loaded at first, the program
 can create a new 24bit 600x600 bitmap in pseudo color for your use.
 If a calibrated bitmap raster map file is already loaded, then load
 its corresponding SRTM .hgt data file from the Tools->SRTM->load menu.
 Now you can scroll to the region of interest and press the 3D button
 to view the 3D image. The default view is towards North at x1 zoom
 level using a simple planar pseudo color model (takes about 10s).  
 The x1 zoom level has a horizontal scale of 3"/pixel or about 93m/pixel.
 That is, a 240 pixels wide screen implies a length about 22km.
 The eye angle is measured with respect to normal (that is, 0 deg.
 is the top/vertical view. Default is 60 deg.). The detailed wire-frame
 models are useful at at higher zoom levels and take a little longer
 time to display (20s). The gray scale model views are lit from eye
 direction (invert the image to see lighting from the opposite side).
 The texture menu texture maps your raster image onto your elevation 
 data map to create a 3D view. Texture mapping works best only when your
 raster image file is also exactly 1200x1200 wide. Be patient, as each 3D
 view may take about 10 to 20 seconds to generate. Your poor PocketPC has
 no floating point processor, no graphics accelerator, and no Direct3D
 software (in WinCE 4.2)!

 This is a beta test version. A more detailed help file will be
 available later. If you have any doubts now, you can e-mail me.
 Have fun!

  C. Mathiazhagan
 (cmathiaz@yahoo.com)