DTM FAQ

VR GIS
This page updated: April, 2011

DTM Installation

Answer... This program is all in 1 zip file. Create a directory and place the zip in there. Unzip it and then create a shortcut to the program (dtm.exe). Move Dlls To System32 if you have XP, or Move Dlls To System if you have Win98 [ZipDll.dll, UnzDll.dll, dzsfxus.bin]. The DTM Information htmls are in a separate zip file. The source code is all in the src.zip file [except the DelphiZip component: See Zip ReadMe.txt for link]. Unzip the src.zip and compile with Delphi... or delete the src.zip.

Be advised that the Ecotype Print button activates a BDE database and BDE IS NOT PART of this package. If BDE is not already on the computer it is necessary to get a program that installs BDE (or DO NOT press that button!). (VR GIS™ DOES INCLUDE BDE installation... there are many programs available that also install the BDE database drivers and dll's) The other database activities of this program do NOT require BDE... they also are not Paradox .db files containing BLOB data (images).

DTM Frequently Asked Questions

Digital Terrain Mapping (DTM)™: Produce Elevation Tints, Slope Tints, Contours, Line of Sight, LOS Masked Areas, and 3D Flyby Perspective Views using Digital Elevation Model (DEM) data from USGS or NASA Planets : Mars Mola latest .tab and .img Viking data , NOAA Etopo 5 Minute , NOAA Global Land One-km Base Elevation (GLOBE) : ftp from here , Gtopo 30 arc second , NIMA - DTED™, etc. download center , USGS 1:250,000..1:24,000 , NED , SRTM (U.S.A. 90 and 30 meter) data at jpl.nasa , Washington 10 Meter Dem , ESRI® .grd code: Phil Scadden, Surfer .grd code: Aaron Hochwimmer, VTP.bt files, Ascii.xyz files, and binary integer elevation data optionally skipping a defined size header using inputs for the x and y size of the file. In constant evolution since the early 80's MICRODEM is a microcomputer mapping program written by Professor Peter Guth... and Paul Bourke should write a book... just collate all the html pages and rewrite the C source into pascal. Richard Horne does Terrain Visualization and Sonograms for bird songs...!

Answer... Download and import the TerrainBase/ETOPO5 Digital Elevation Model (DEM) and Shape files (.shp) of your selected area and topic. Visit links to other DEM/Raster Image and SHP files. From the main program form open the etopo5.htf and then open the .shp file(s) to over lay on top of the terrain. Mouse move to select an area then press [Ctrl+Shift] - Left mouse button to activate the 3D view of the area.

Answer... There is some variation in the resolution between the Shape file and a DEM

Large "shifts", expecially when it is obvious that the "shift" is always shifted in a direction is due to the DEM and the Shape file being of DIFFERENT Datums even when of the same Projection!

Two different projections will cause LARGE variation in overlap... current version DOES NOT do projection correction - even though it has ALL those pages to input the information...

DTM Version 1.1 Bug list

DTM To Do: