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-
- ___________________
-
- EarthMap user guide
- ___________________
-
-
- User, please note
- =================
-
- EarthMap is Freeware, i.e. it is free software.
-
- Copyright notice
- ================
-
- The copyright (c) of this program belongs to John Kortink. All rights are
- reserved.
-
- You may not change this program (except for documented configuration
- changes). You may not use any part of this program in any other program or
- product without my written approval. You may spread this program freely, but
- only in complete and unchanged form, and only against bare distribution costs
- (if any). This program is provided 'as is'. No fitness of this program for
- any particular purpose is implied. Using this program is entirely at your own
- risk.
-
-
- //
- //
- // Introduction
- //
- //
-
- EarthMap is an electronic globe. It draws on a huge database consisting of
- 5,719,617 line segments, describing coordinates and shape of a number of
- natural and man-made features on Earth. This includes coastlines, country
- borders, rivers, lakes, canals, glaciers, etc..
-
- EarthMap provides an extensive array of viewing facilities, including pan,
- zoom and coordinate entry. In addition, any view may be saved as a Draw file.
- EarthMap is also very fast. Special care has been taken to make view updates
- as fast as possible.
-
- The database used by EarthMap is the 'CIA World Data Bank II'. This database
- originally consisted of 130Mb of COBOL records. It was compressed from COBOL
- records to a more compact representation (leaving around 13Mb of data) by
- Brian Reid. The database itself has been put in the public domain by the
- government of the USA.
-
- You probably received EarthMap without the database files. The easiest way to
- obtain them is from Internet. For example, from ftp.digital.com, directory
- /pub/graphics/data/cia-wdb, subdirectories africa, asia, europe, namer and
- samer. The empty files in the !EarthMap.Maps directory should be replaced by
- the appropriate database files. Incidentally, the database files can also be
- found on the CD-ROM supplied with RISC PC StrongARM processor cards,
- directory 'SOFTWARE.EARTHMAP', archive files AFRICA, ASIA, EUROPE, NAMER and
- SAMER.
-
- EarthMap can work with any subset of the database files. If a particular
- database file is absent or is found to have invalid contents, the part of the
- globe corresponding to the database file will simply be missing.
-
-
- //
- //
- // Using EarthMap
- //
- //
-
- On EarthMap's iconbar menu the usual 'Info' and 'Quit' icons can be found. In
- addition, 'Control', 'Detail', 'Cache' and 'Save' give access to the
- 'EarthMap control', 'EarthMap detail', 'EarthMap cache' and Draw file save
- windows (click on the menu entry to make the window permanent) and 'Status'
- gives access to the 'Status' menu. The 'EarthMap control', 'EarthMap detail',
- 'EarthMap cache' and Draw file save windows and the 'Status' menu are
- described below.
-
- Clicking SELECT or ADJUST on EarthMap's iconbar icon will open the 'EarthMap
- view' window (or, if it is already open, redraw it). The 'EarthMap view'
- window is described below.
-
-
- //
- //
- // The 'EarthMap view' window
- //
- //
-
- This window (from now on called 'the view' for short) is your window on the
- globe. There are several ways to pan and zoom the view :
-
- - Double-clicking SELECT or ADJUST inside the view. The view is panned so
- that the globe point clicked on is at the centre of the new view.
- - Double-clicking SELECT or ADJUST inside the view, holding down a CTRL,
- SHIFT or ALT key. The view is zoomed (SELECT = zoom in, ADJUST = zoom out).
- The amount of zoom depends on the key held down (ALT = factor 4, SHIFT =
- factor 2, CTRL = factor 1.5). Also, the view is panned so that the globe
- point clicked on is at the centre of the new view.
- - Dragging a 'box' around an area of interest inside the view. The view is
- panned and zoomed so that the selected globe section, at its maximum size,
- is entirely visible inside the new view, and that the centre of the
- selected globe section is at the centre of the new view.
- - Using the 'EarthMap control' window, 'Coordinates' part. Enter the required
- longitude and latitude coordinates of the new view centre and click on the
- 'Go to' button.
-
- There are a couple of important things to note about the view window :
-
- - The 'world' basically consists of a coordinate rectangle stretching from
- -180 to +180 degrees longitude (horizontal) and from -90 to +90 degrees
- latitude (vertical). The view window shows this world in 'wraparound' mode
- (to simulate a globe), which effectively means that -180 and +180 degrees
- longitude appear as direct neighbors in the view window, as do -90 and +90
- degrees latitude. While the 'longitude wrap' is correct, the 'latitude
- wrap' obviously isn't (the North and South poles are not neighbors !).
- However, this feature allows much more freedom of movement around the
- globe, in addition to having some entertainment value.
- - As there is no real 'end' to the globe, the function of the view window's
- scroll bars is slightly unusual. Due to the way the 'wraparound' feature is
- implemented, the view window is actually a view on not a single world, but
- on a large array of identical worlds, stacked together in both vertical and
- horizontal directions. But a maximum of only a single world is visible in
- the view window. This makes dragging the scroll bars somewhat useless for
- panning around the globe (resulting movements are too coarse). However,
- clicking the scroll bar 'arrows' is still quite useful.
-
-
- //
- //
- // The 'EarthMap control' window
- //
- //
-
- In this window, you will find two parts, called 'Coordinates' and 'Draw
- file'.
-
- The 'Coordinates' part provides a longitude/latitude coordinate display.
- Setting the display to a coordinate and then clicking 'Go to' will pan the
- view window so that the coordinate specified is at the new view centre.
- Clicking 'Get' will set the display to the coordinates of the current view
- centre.
-
- The 'Draw file' part allows you to set the page size that is specified in any
- saved Draw files. The default of 8.27 x 11.69 inches is standard A4 size.
-
-
- //
- //
- // The 'EarthMap detail' window
- //
- //
-
- This window enables detail manipulation.
-
- The database contains information on several different Earth feature types
- (each type is called a 'detail' in EarthMap). Each detail belongs to a detail
- group. Each detail group ('Boundary', 'Coast, islands & lakes', 'Rivers' and
- 'USA state lines') is stored in a seperate database file (the files ending in
- 'bdy', 'cil', 'riv' and 'pby' respectively).
-
- Every detail has an on/off flag. If a detail is 'on', it is displayed in the
- view and saved in Draw files. If a detail is 'off', it is ignored (as if it
- were not present in the database). The 'All on' and 'All off' buttons may be
- used to switch on/off all the details in a detail group.
-
- Every detail has a colour. This is the colour used to render the detail in
- the view and in Draw files. Under RISC OS 3.5 and later the colours may be
- edited by clicking on the colour box, which will pop up a standard 'colour
- picker' window. Under RISC OS versions before 3.5 the colours cannot be
- edited.
-
-
- //
- //
- // The 'EarthMap cache' window
- //
- //
-
- This window enables cache manipulation.
-
- Every database file has a cache on/off flag. If a cache flag is 'on', the
- database file is cached. If a cache flag is 'off', the database file is not
- cached. The 'All on' and 'All off' buttons may be used to switch on/off all
- the cache flags.
-
- EarthMap needs continuous access to the database files, so the speed at which
- these can be accessed is quite important. If a database file is cached, it
- can be accessed much quicker, at the expense of some of your available
- memory. If you have the memory to spare, it is a good idea to cache all the
- database files.
-
-
- //
- //
- // The Draw file save window
- //
- //
-
- This window enables you to save the current view as a Draw file.
-
- The page size specified in the Draw file may be set in the 'EarthMap control'
- window, 'Draw file' part.
-
-
- //
- //
- // The 'Status' menu
- //
- //
-
- In this menu you can manipulate EarthMap's 'status', which consists of a
- number of configuration settings.
-
- - 'Save' will save the current status.
- - 'Load' will load the saved status.
- - 'Default' will load the default status.
- - 'Kill' will remove the saved status.
-
- When EarthMap starts up it loads the saved status, or the default status if
- there is no saved status.
-
- The status consists of the detail flags and colours ('EarthMap detail'
- window), the cache flags ('EarthMap cache' window) and the Draw file page
- size ('EarthMap control' window).
-
-
- //
- //
- // Epilogue
- //
- //
-
- Updates of EarthMap will be made available by (in order of preference) :
-
- - World Wide Web, on www.inter.nl.net/users/J.Kortink.
- - Electronic mail, to kortink@inter.nl.net.
- - Snail mail, to : John Kortink, Nutterbrink 31, 7544 WJ Enschede, The
- Netherlands. Include a DD or HD floppy, return envelope and one
- International Reply Coupon (IRC).
-
-