SAmaps.TXT            South American MAPS Summary
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SAmaps03.zip:  Street level maps of Maracebo

SAmaps04.zip:  All of Venezula has now been mapped to the 1,000,000 scale 
               and all of these maps were moved to the VZ subdirectory.  

SAmaps05.zip:  Changed all of the roads to color 12 instead of 4 to
               improve map visibility...

SAmaps06.zip:  Added map of Brazilia
               Moved all maps to subdirectories of PANAMA and SAMERICA

SAmaps07.zip:  Finished off the 5 degree box around Brazilia

The South American maps for Maracaibo were digitized using the
MAPFIX23 program and a large digitizing tablet.  The source
maps were provided by the customer.  This file describes what
still needs to be done for Maracaibo and how the raw map data 
was generated.

The SAnorth and south and SAMadero.maps made by LU7ABF in Argentina 
are also included.


THINGS TO BE DONE:

LABELS:  Labels need to be added by someone who is Knowledgable 
of Spanish and the local area and knows what landmarks are the best 
reference points.  Since labels can only be 12 characters, abbreviations
are needed.  Use MAPFIX23 and the LABELS-ADD command to add labels at the 
cursor.  Choose labels to appear at finer and finer levels of detail.  
There is a limit of 199 labels per map.

LARGER MAPS:  The underlying 1 mile maps are the originals.  To provide
a larger view, the VZMrcbo.map was build by consecutively overlaying 
each of the other maps and using the EDIT-NEW, and EDIT-ADD commands to
draw roads over the finer detail from the overlay.  This was done rather
quickly with out real attention to detail, since the larger map does not
need to be as accurate.  This map is FULL.  If more detail is needed,
the map can be split in two a northern half and a southern half and the
process continued.  This TASK-OVERLAY command is very useful for checking
one map against another...



BACKGROUND ON THE PROCESS USED TO DIGITIZE MARACAIBO MAPS:

MAPFIX needs three things in order to produce a map.  It needs an 
upper reference point and a lower reference point.  These points need 
to be widely separated in longitude.  The X and Y differeces between 
these points establishes the X and Y scale factors.  Finally, the map 
must be perfectly aligned north/south and east/west.

    All source maps were ASSUMED to be oriented with the bottom 
edge on a perfect east/west line.  The two most widely separated
points on each map were used as the reference points.  All other
reference points were then plotted according to their LAT/LONG
values and compared with the marked locations.  The offset of
all points were then averaged and a best-guess for the actaul
locations of the two reference points were asjusted to minimize
the total error for all points.  These NEW locations for the
two reference points were then marked on the source map and
also ploted on the PPRS maps.  The value of these reference
points are also included in the comments field for the maps.

If future surveys determine that adjustments to these maps need
to be made, or if the original source points were in error, then
adjustments to all the data points can be made as either offsets,
scale, or rotations about these points.  The following table
describes the lineage of the maps as they were developed.

   MAP      SIZE   REF1 REF2 CHECKED         COMMENTS
   -------- ----   ---- ---- --------------  --------------------
   VZMrcb01   2     2    8    1, 3, 4, 6     Digitized
   VZMrcb02   2     2    8    1, 3, 4, 6     Digitized
   VZMrcb03   1     9   10   11,13,14,16,23  Digitized
   VZMrcb04   1     9   10   11,13,14,16,23  Digitized
   VZMrcbUV   1                              Extraced fm 1,2,3,4
   VZMrcb05   1    22   19   10,17,18,23     Digitized
   VZMrcb35   1                              Extracted fm 3 & 5
   VZMrcb06   1    22   19   10,17,18,23     Digitized                             
   VZMrcb46   1                              Extracted fm 4 & 6
   VZMrcb07   1    22   19   10,17,18,23     Digitized
   VZMrcb08   1    22   19   10,17,18,23     Digitized
   VZMrcb09   2    22   19   20              Digitized & some 7&8
   VZMr3456   1                              Extracted fm 3,4,5,6
   VZMarcbo   8                              Drawn from overlays 
                                             of all other maps
   VZ       256                              Map sketch from
                                             Encyclopedia


