FE 'tkGooies' system
'MAPtools' group
CONTINENTS and REGIONS
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The FE 'MAPtools' scripts may allow for assigning colors to different countries/regions/lakes in an 'outline' file --- someday. (The colors would be used in doing 'polygon fills'.) |
! Preliminary !
Should have data for more regions.
Furthermore:
Some data may be replaced by better data.
! Note !
More links to sources of CONTINENTS and REGIONS
outline data (in ASCII-text format) may be added
--- as 'MAPtools' scripts are tested and
developed for the FE 'tkGooies' subsystem.
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INTRODUCTION : The following continent and region 'outline files' were created from KMZ (or GeoJSON) files using a rather tedious process --- such as the following for KMZ files:
Various Data Resolutions For each continent/region, there may be several outline files (below) of different 'resolutions' (numbers of points). The filename of each file includes the number of lines in the file. That number is an indication of the number of data lines (point definitions) in each file --- and includes the number of comment lines (usually less than 10). The more lines in the file, the more data points. More data points means that a plot of the sequences of points will (usually) yield a map outline with more detail. --- Note that you can estimate the number of points that you will need to get a high-quality outline of a continent. Nowadays, the maps are often rendered on a display screen with a resolution of about 1024 x 768 pixels or 1920 x 1080 pixels --- with the resolution trending upward year by year. Let us take the case of a 1024 x 768 pixel computer monitor. Say we want to render a map in a web browser window on that display. If the user has the web browser window maximized, a map of about 800 x 600 pixels would probably fit nicely within the margins of the web browser viewport. If we are dealing with a map of a continent (or region) that is rather rectangular in shape (like Australia-Tasmania) and with about an 8-to-6 aspect ratio, then --- if there are not a lot of inlets/jaggies along the boundaries of that continent --- we would need a maximum of about 800 + 600 + 800 + 600 = 1600 + 1200 = 2800 points around the boundary of the continent --- to give a really accurate rendering of the boundary on the monitor screen. Actually, that would usually be overkill. If we had point coordinates about every 4 pixels around the boundary, and we connected those points with straight line segments, we would probably find that we get a quite good-looking map. So about 2800 / 4 = 700 points might give a quite good map. On the other hand, if there are a lot of jaggies around the periphery of the continent (lots of inlets and/or peninsulas, say), we may need up to around 10,000 points to get a 'fine-grained' map image --- like the image at the top of this page. In summary, for outline maps of continents, we will probably want to use from a few hundred to about 10,000 points to draw outline maps. In the map files below, we may eventually want to have several file 'resolutions' for each continent/region --- 'crude', 'good', and 'excellent' files --- say about 200 points, 1500 points, and 10 thousand points, respectively. --- Note that you can easily estimate the file sizes --- in kilobytes --- of each of these crude, good, and excellent files. If each number in the file is expressed to about 10 significant digits, that means that there are about 23 characters in each data line of the file (counting 2 decimal points and a space separating the 2 numbers). Then the file sizes will be
Data 'Loops' Some maps may contain outline 'loops' --- representing islands --- or bodies of water --- or multiple continents --- or multiple countries. The loops are indicated in the data files by a blank or comment line between sequences of data lines. (The comment line could contain a red-green-blue color specification, for the 'fill' color of the next 'loop'.) A comment line is indicated by a '#' character in column one of a file line.
Presentation of the files The following 'table of contents' (table of links) offers a way to quickly jump to a section of continents or a section of regions (groups of countries). You can either
Lists of regions Here is a list of about 180 countries gathered into regions of Earth. Eventually, there may be various groupings of these countries in the outline-data-files below. |
TABLE OF CONTENTS:(links to sections of this page, below)
End of Table of Contents.
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CONTINENTS:
< Go to Table of Contents, above. >
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Sample plot - from North Africa file below.
REGIONS:
< Go to Table of Contents, above. >
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Sample plot from Asia file above
Sample plot from Western Europe file above
Sample plot from Middle East file above
NOTE1:
Because these outline data files are
'plain text' files, they can be
easily edited to move or copy data
for countries between files.
For example:
Move or copy data for African countries
between the North and South Africa region-files
--- or between the Western and Eastern Europe
files.
Or make new files that contain
country combinations that are not quite
like the combinations in these files.
(Avoiding duplicate, not-quite-matching
boundary lines can be a difficulty.)
NOTE2:
The
'tkReadOutlineFile_ drawOutlineOnCanvas'
'tkGooie' that was used to make these plots
may be enhanced to accomodate
plotting files with data that crosses the
international date line --- switching suddenly
from 180 degrees to -180 degrees as
one goes eastward.
This will help with plotting :
* Australia and nearby islands
* Alaska including the far western Aleutian islands
* Russia including far eastern Siberia.
NOTE3:
The
'tkReadOutlineFile_ drawOutlineOnCanvas'
'tkGooie' that was used to make these plots
may be enhanced someday to read colors
from comment lines in the outline file ---
and plot countries/regions/lakes in color.
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SAMPLE SEARCHES for ASCII map files
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Page was created 2016 Nov 12.
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