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- Documentation contents:
-
-
- INTRODUCTION
-
- Background (MS-DOS)
- Micro WDB II File Composition
- Disclaimer
-
- WORLD DATA BANK II (Amiga) Display Routine, Version 2.2
-
- Overview
- Instructions For WDB
- Running WDB
- Forcing Use of a Single Data File
- Adjusting Aspect Ratio
- Navigating The Display
- Choosing A New Vantage Point
- Known Bugs
- Instructions For SAT
- Instructions For SELECT
- Credits
-
-
- _____________________________________________________________________
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- INTRODUCTION
- ============
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- The following information is from the original MS-DOS
- version of the WDB-II program, written by Fred Pospeschil.
- It explains the background of the CIA derived map data
- for those who are interested (or might have the resources
- to replace the data with something more current).
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- The full WDB-II is a digitial map data base produced by the Central
- Intelligence Agency (CIA) and distributed by the National Technical
- Information Service (NTIS), U.S. Department of Commerce, 5285 Port
- Royal Road, Springfield, VA, 22161. Micro WDB-II is a highly
- compressed version which is suitable for use on micro computers and
- was put in this configuration by Micro Doc. Before describing Micro
- WDB-II a few words should be said about the source file - WDB-II. The
- following paragraphs are paraphrased from the NTIS overview of WDB-II.
-
- WDB-II is a digitial representation of the world coastlines
- and boundries suitable for use in automated mapping systems.
- It contains approximately six million discrete geographic
- points and was digitized using all available sources of
- information. Map scales used range from 1:750,000 to
- 1:4,000,000 with a nominal scale of 1:3,000,000. These points
- are grouped by and identified as describing (1) coast lines,
- (2) country boundries, (3) state boundries (USA only), (4)
- islands, (5) lakes, and (6) rivers. Each of these groupings
- is further broken down into features and subordinate
- classifications/ranks. These ranks are hierarchically
- structured, and are also used for plotting symbol definition.
-
- WDB-II, as provided by NTIS, is in a 20 character format
- on five 9 track EBCDIC one-half inch magnetic tapes. This data
- base consists of two types of records, one for the line segment
- identifier data, and the other for the latitude and longitude
- values of each discrete point making up the line segment. In
- this format latitude and longitude values are recorded only as
- integers in degrees, minutes, and seconds. WDB-II is available
- for $660.00 (Order Number PB-271 874 SET/HBG).
-
- Clearly, WDB-II is an excellent data source when making large (4 x 6
- foot) plots on a mainframe or minicomputer. It is, however, somewhat
- large (150 - 200 megabytes) for use on microcomputers. Even on the
- larger commercial online graphics systems, many points have to be
- filtered out before generating displays. For this reason many people
- have spent considerable time over the past to filter and compress this
- data into a form which could be used in desktop computers. To these
- people we wish to express our appreciation - particularly Antonio
- Riveria who provided us with a copy of the latest download of the
- file.
-
-
- Background
- ==========
-
- The present version began as a three megabyte ASCII text file which
- contained some 179,000 points selected from all six of the line types
- described above. This file was then converted into a sixteen bit
- integer format which reduced the size to just over one megabyte. Since
- this was still a little large for most five inch disk formats the file
- was divided into six files - one for each of the six line types. The
- coast line file was further divided into two files as it was over 400
- KB. With this processing completed the file was configured such that
- it could be readily moved to most desk top microcomputers using the
- MSDOS disk format. The following table provides a brief statistical
- overview of the six line types which are contained in the data base.
-
-
- Micro WDB-II File Composition
- =============================
-
- Detail COAST COUNTRY STATE ISLAND LAKE RIVER Total
- Level .PNT .PNT .PNT .PNT .PNT .PNT
-
- 1 29150 8573 798 13781 5886 11146 69339
- 2 35077 10172 959 16077 7080 13217 82599
- 3 5470 1496 153 2524 1023 1817 12526
- 4 4000 1249 101 1945 820 1254 9502
- 5 1478 869 248 844 309 760 5365
- Total 75175 22359 2259 35171 15118 28194 179331
-
- Lines 208 301 111 344 103 196 1263
-
- Size (KB) 449 134 14 211 90 169 1067
-
- The above table shows the number of points which are in each file and
- for each level of detail. It also shows the number of line segments
- in each file and the file sizes in kilobytes.
-
- Detail level 5 contains the fewest points and produces the least
- detailed graphics image. The points at each level of detail are
- additive to the points at all lower levels. For example, when using
- detail level 4 the points from both levels 4 and 5 must be used /
- retrieved. Therefore, if one were drawing coast lines at detail level
- 4, a total of 5478 (4000 + 1478) points would be processed. These 5487
- points will describe 208 line segments of various lengths.
-
- [NOTE: For the Amiga version, the structure of the data
- as described above has been altered. Detail level 1 now
- incorporates all data from the lower levels. It also
- combines data from each of the six groups into a single
- file. Lower detail level files are subsets of the detail
- level 1 file, and similarly incorporate all data from
- levels below them. The statistical distribution of the
- data points otherwise remains as described.]
-
- Note that the same number of line segments exist at all levels of
- detail. For example, regardless of which level of detail is selected,
- there will always be 208 line segments described by the coast line
- data file. In some cases, mostly in the islands file, line segments
- degenerate to single points at the lower levels of detail. Therefore,
- programs which process this data must check to see whether each line
- segment header record is followed by a point record or another line
- segment record. More will be said about this later.
-
- Actual use of the data in these files has shown that most displays
- which cover a reasonably large area do not need all of the detail
- provided at level 1. A large area would be a major portion of the
- U.S. For large area plots level 3 or 4 is normally sufficient and
- greatly reduces the number of points which must be processed.
-
-
- Disclaimer
- ==========
-
- This product contains/uses data and/or code placed in the public
- domain by Fred Pospeschil and Antonio Riveria. Original coordinate
- data was created by the Central Intelligence Agency.
-
- ALL USERS OF THESE MATERIALS ARE TOTALLY RESPONSIBLE FOR THEIR USE AS
- THESE MATERIALS ARE PROVIDED WITHOUT EITHER EXPRESS OR IMPLIED
- WARRANTIES OF ANY KIND.
-
- For information related to the original MS-DOS version only:
-
- Fred Pospeschil
- 3108 Jackson St.
- Bellevue, NE 68005
- 402-291-0795 (6-9 PM Central)
-
- _____________________________________________________________________
- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-
- WORLD DATA BANK (Amiga) Display Routine, Version 2.2
-
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- OVERVIEW
- ========
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- This program displays the CIA database of the geography of the world.
- The executable file is under 11K, and its takes about 137K to execute,
- including hi-res interlace screen and intuition interface.
-
- Features:
-
- ╖ Slider gadgets for adjusting latitude, longitude and
- magnification factors
- ╖ Integer arithmetic for scaling, hence faster calcs
- ╖ Area clipping to avoid spending time plotting off-map points
- ╖ Compensation for monitor "stretch" (aspect ratio distortion)
- ╖ Automatic centering of next display from any point in current
- display
- ╖ Choice of cylindrical or spherical projection
-
- The files in this set are described as follows:
-
- LEVIATHAN.LHA -- This enormous archive conatins the master 1.1 Meg
- data file for use with both the WDB and SAT display programs.
- The Big File, WDB.1.ALL, contains the data points in all six
- groups described above. It can be broken down by the SELECT
- program into four smaller subsets named WDB.2 through 5.ALL.
- (WDB.5.ALL has also been provided separately to allow you to
- run the program without extracting this archive). These
- smaller data files also will contain data from all six groups,
- but provide correspondingly faster drawing and less detail.
- The WDB.5.ALL subset furnished is the smallest, fastest, and
- least detailed.
-
- SAT -- This executable program draws a spherical view of the Earth
- from a fixed altitude approximating 30,000 miles. It uses the
- WDB.5.ALL data file (the smallest, with least detail). The
- latitude and longitude of your vantage point are adjustable.
-
- SAT8 -- This is a special version of the SAT program above for use
- ONLY ON MACHINES EQUIPPED WITH A MATH CO-PROCESSOR. *WARNING!*
- This program *WILL CRASH* if run on a machine not so equipped.
-
- SELECT -- This program may be used to create one or more of the
- four data files which are subsets of The Big File.
-
- WDB -- The World Data Bank executable program draws a cylindrical
- projection of the Earth. Your vantage point is adjustable in
- latitude, longitude, and "altitude" (magnification factor).
- WDB automatically chooses one of the five data files to use
- based upon the magnification factor selected.
-
- Other files -- Also included are icons for Workbench executable
- programs (WDB.info, SAT.info), along with smaller alternate
- icons for each (WDB.alt.inf, SAT.alt.inf). To use the alter-
- nate set of icons, simply delete WDB.info and SAT.info from a
- CLI, then rename WDB.alt.inf as WDB.info and SAT.alt.inf as
- SAT.info.
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- INSTRUCTIONS FOR WDB
- ====================
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- You may run WDB or SAT using the smallest (least detailed) data file
- right now simply by clicking on either icon. If you wish to see
- greater detail you'll need to dissolve the LEVIATHAN.LHA archive,
- placing the resulting WDB.1.ALL file in the same directory as the WDB
- and SAT programs. As explained below, you will probably want to use
- the SELECT program to create the intermediate data files between The
- Big File and WDB.5.ALL, but it's not necessary, especially if disk
- space is too tight to waste on redundant data.
-
-
- Running WDB
- ===========
-
- To call it from CLI, type: WDB <optional data file name>
- To call it from Workbench: double click on the WDB icon
-
-
- WDB Automatically selects the input file based on the magnification
- factor chosen according to the following scale:
-
- mag 0.85 - 2.00 --> wdb.5.all ( 25,890 bytes)
- mag 2.00 - 6.00 --> wdb.4.all ( 82,080 bytes)
- mag 6.00 - 12.00 --> wdb.3.all ( 156,960 bytes)
- mag 12.00 - 36.00 --> wdb.2.all ( 652,428 bytes)
- mag 36.00 - 125.00 --> wdb.1.all (1,068,408 bytes)
-
- The name of the file being shown appears in the lower right of the
- Control Window. If the automatically selected file is not available
- in the current directory, the next most accurate file (lower numbered
- file) available is used. Note that the size of the file and the
- detail available for display increases for *lower numbered* files.
-
- Using various files allows for displays of greater magnification to
- maintain better detail without the time penalty of passing through the
- largest file for displays which require lesser detail. Perhaps someone
- will have some better ideas for correlating the magnification scale to
- the different data files. Speak up!
-
-
- Forcing Use of a Single Data File
- =================================
-
- From CLI, specifying a datafile on the command line will cause WDB to
- supress automatic file selection, instead using only the file
- specified. For example, "WDB WDB.3.ALL" will display only points
- from the file WDB.3.ALL.
-
-
- Adjusting Aspect Ratio
- ======================
-
- There is a Distortion Comp(ensation) factor control designed to
- compensate for monitor "stretch" that will be different for different
- monitors. The program defaults to a value of 1.2, figured at the
- equator, which seems to work best with the 1080 monitor. It may
- require some experimentation to find a setting that produces
- acceptable results with other monitors. Try looking at the shape of
- Africa on a good globe and adjust the value in the Distortion Comp
- text gadget until the shape of Africa on screen approximates that of
- the globe.
-
-
- Navigating The Display
- ======================
-
- Using one of the available data files, WDB draws a cylindrical
- projection of the world's coastlines, political boundaries (including
- states in the U.S.), islands, rivers, and lakes. The default vantage
- point is at the junction of the equator and the Greenwich meridian.
- A default magnification factor of 1.0 provides a projection of the
- entire globe.
-
- On screen is a control panel offering an intuitive set of controls.
- They include both text gadgets and sliders for selection of the
- longitude and latitude in degrees and minutes, and the "altitude"
- (magnification factor) of your vantage point over the earth. You may
- adjust the sliders to an approximate value, or enter a precise value
- in the text gadgets from the keyboard. Menu items allow you to
- hide/show the menu bar and remove/restore the control panel for screen
- captures. The PLOT button draws a screen according to the control
- panel settings; the QUIT button quits the program. A drag bar on the
- control panel allows it to be moved to a different location on screen.
-
- Maps are drawn with colors which indicate the class of data points to
- which they belong. Continental coastlines are dark green, islands are
- bright green, rivers and lakes are dark and light blue, respecively,
- major political boundaries are red and minor ones (states) are yellow.
-
- At greater magnifications, and especially with the more detailed data
- files, the program may at times appear to halt momentarily. This is
- normal, as the program clips data which falls out of bounds of the
- window displayed on screen. When drawing is concluded the control
- window will reappear.
-
- If you end up with a completely black screen when the control panel
- reappears, you've chanced upon a section of the globe which is
- entirely devoid of features, such as an ocean. To regain your
- bearings, reduce the magnification factor and replot.
-
-
- Choosing A New Vantage Point
- ============================
-
- If you haven't a clue to the latitude and longitude of a location
- you'd like to examine, WDB has a feature which allows you to select a
- point on the current display with a click of the Left Mouse Button.
- This will set both the longitude and latitude to that point, which
- becomes the vantage point for the next display. To avoid having a
- desired vantage point end up off the screen, you should make the
- selection of your target vantage point before experimenting with
- greater magnification factors. [See "Known Bugs"]
-
-
- Known Bugs
- ==========
-
- I've noticed that when the magnification factor is low (around 1.0 -
- 3.0), the mouse pointer location does not convert very accurately into
- longitude and latitude. I'm not sure why. Perhaps rounding. (??)
- The WDB program uses integer arithmetic (i.e., fixed-point math) to
- gain speed. This introduces rounding.
-
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- INSTRUCTIONS FOR SAT
- ====================
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- This program displays a single data file as a two-dimensional
- projection of a sphere. Unlike WDB, SAT's "altitude" is fixed at
- around 30,000 miles. Therefore SAT does not use multiple data files.
- In this version the program expects to read the smallest, fastest, and
- least detailed data file (WDB.5.ALL) since not much detail is visible
- at this altitude.
-
- Slider gadgets allow you to change the coordinates of the nearest
- visual point of the sphere (your vantage point). The vertical slider
- adjusts latitude; the horizontal one is for longitude. You may also
- choose to enter a specific number (in degrees) directly via the text
- gadgets. In this version, SAT does not allow the selection of
- latitude and longitude coordinates from the mouse pointer.
-
- There are two versions of this program:
-
- SAT - the regular version
- SAT8 - a special version for those with M68881 math co-processors.
-
- NOTE: DO NOT ATTEMPT TO RUN SAT8 IF YOUR SYSTEM IS NOT EQUIPPED
- WITH A 68881 MATH CO-PROCESSOR OR A CRASH WILL OCCUR.
-
- Both programs use the same data files as WDB, although in the current
- version, both look for a file called "WDB.5.ALL". If you prefer to
- view more detail (and can afford the wait) you may spoof the program
- into using a different data file by renaming it as WDB.5.ALL. Simply
- copy one of the more detailed (lower numbered) files to a different
- directory under the name of "WDB.5.ALL" and run SAT from that
- directory.
-
- For example, if you have the SAT program on df0:, type in a CLI:
-
- cd ram:
- copy df0:wdb.4.all ram:wdb.5.all
- df0:sat
-
- SAT has many more calculations to complete than does WDB to plot a
- map, hence it takes quite a bit more time. Here, too, the display may
- appear to halt for a period during the drawing process. This is
- normal. When drawing is completed, the control panel will reappear on
- screen.
-
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- INSTRUCTIONS FOR SELECT
- =======================
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- The SELECT program is used to extract lower level data segments from a
- higher level data file. This program enables us to put the entire WDB
- collection on one disk. The price to be paid is that you must extract
- the files named WDB.2.ALL, WDB.3.ALL and WDB.4.ALL from The Big File
- yourself (if you intend to use them). Note that it's not manadtory to
- extract these files; both WDB and SAT will work with any single data
- file or any combination (be sure to read the Instructions For SAT).
- By choosing not to extract the three intermediate files you'll lose
- only the speed advantage gained by not sifting through The Big File
- for low and medium magnification viewing.
-
- All four lower level data files (WDB.2 through .5.ALL) are merely
- subsets of The Big File, and SELECT can extract any one of them
- directly from it. Similarly, each lower level file is a subset of all
- higher level files, and SELECT can extract any lower level from any
- higher level file. Here, as elsewhere in this document, "lower level"
- refers to filenames which are numerically HIGHER.
-
-
- To use SELECT from the CLI: SELECT <sourcefile> <destfile> <level #>
-
- The level number of the source file must be numerically lower than the
- level number requested for the new file. The program will copy from
- the source file to the destination file only the records with a level
- number greater than or equal to the requested level number.
-
- For example, to create WDB.4.ALL from The Big File enter:
-
- SELECT WDB.1.ALL WDB.4.ALL 4
-
-
-
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
- CREDITS
- =======
- ~~~~~~~~~~~~~~~~~~~~~~~~~~
-
- The program is the work of
-
- Mike Groshart: basic design; porting from Pascal
- Bob Dufford: intuition interface; speed optimization
-
- Send us further suggestions and bugs to be fixed in care of:
-
- Amiga Users of the Heartlands
- P.O.Box 1432, DTS
- Omaha, NE. 68101
-
- E-mail:
-
- Larry's Hot Tub: 402-571-4316 [1:285/15.0@fidonet]
-
- Internet:
-
- mike.groshart@auoh.omahug.org
- bob.dufford@auoh.omahug.org
-
- Or route a message through Portal or BIX ID: cletus
-
-
-
- World Data Bank II for the Amiga, version 2.2 by Bob Dufford and
- Michael Groshart. This product uses data and code originally placed
- in the public domain by Fred Pospeschil and Antonio Riveria. Original
- coordinate data was created by the Central Intelligence Agency.
- Your tax dollars at work.
-
- Anyone with access to a more recent version of the coordinate data
- is welcome to provide it; a lot has happened to the world's political
- boundaries since this was first released. :-7
-
-