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ESRI
Shape Files are vector files that contain
geographical data and optional attributes. Shape files can
support point, line and area features. Each layer is stored
separately. An ESRI shape file consists of main file (.SHP), an
index file (.SHX) and attributes dBASE table (.DBF).
Use
the main menu / File / Open or Merge
function to import an ESRI shape file and convert it into the
Mapwel map. Then you can upload it into the GPS unit.
As
the shape files are primarily not designed to use with GPS units
and attributes of objects are specified by user, Mapwel cannot
assign the shape file attributes (data) to the map object properties
like Name, Comment, Type, etc. automatically. User is prompted
to assign available shape file data to the map objects.

Because layers are
stored in a separate shape files, it is necessary to Merge
(with use of main menu>File>Merge command) all shape files to create complete map in
Mapwel. Mapwel stores whole map in a single MPW file.
Loading
of each SHP file involves three steps:
1.
Selection of projection and datum used for representation of
geographical data in SHP file.
2. Assignment of SHP attributes to types used by Mapwel.
3. Assignment of other SHP attributes representing name, comment,
street name, phone
number and other data to Mapwel data structures.
Step
1 - Selection of
projection and datum
Use
the first tab in the SHP open file dialog to select coordinate
system of the SHP file. You have to know coordinate system
of the SHP file. If chosen coordinate system is not the right
one, map will be imported improperly.
UTM Zone Number, UTM Latitude Band
Letter and Planar Distance Units are controls for
definition of additional information for UTM system.
Use
Data Size Reduction control
to decrease the number of imported vertices (in case of area and
line objects). If imported data contain too many vertices,
displaying of map on the GPS can be very slow. In such a case,
reduce the size of imported data to speed-up the map displaying.
Reduction of vertices decreases also precision of the map
elements definition. The highest available accuracy of the map
elements uploaded into the Garmin GPS is approximatelly ±1.2 m.
Accuracy of imported data should be lower or equal to this value
to optimize the speed of map displaying and data size.
Border
is an empty space added around the map. Imported map may be
clipped to bounding rectangle of all objects. Set Border to
non-zero value if you need to add empty space around the map.
Click left or right mouse button on the value to
increase/decrease it, or click on 'Border' label to set value
with keyboard.
Click the Next>>
button when you are finished with selection of coordinate system
and data size reduction.

Step
2 - Assignment of attributes to
Mapwel types
If
any of the SHP file attributes defines the type of objects, you
can use this tab to create attribute-to-Mapwel type conversion
table.
Mapwel
cannot recognize meaning of SHP attributes automatically, as
they may contain any type of information. Definition of
conversion table allows user to assign proper type to imported
objects.
You
can skip this step if:
- there is no attribute that defines type of objects
- some attribute already contains Garmin object types
- you do not wish to assign type to objects.

Follow
these steps to create conversion table:
A)
Select attribute that defines the object types.

B) Click on the
first line of the first column in conversion table. Select
attribute value from the pop-up menu that appears.

C) Click on the
second column in the same line. Select type of object from the
pop-up menu. This type will be assigned to all imported objects
that have attribute ROADCLASS set to value Primary.

D) Use Add
button to create as many items in the table as neccessary.
Define all attribute value - object type pairs.

When finished,
click on the Next>>
button.
Step
3 - Assignment of other SHP attributes to Mapwel data structures

If there are
attributes, which define the name, comment or other
Mapwel-compatible data like street name or phone number, use
this tab to assign them to the respective Mapwel variables.
If imported file
has an
attribute that conforms the Garmin area, line and point indexing
system, assign this attribute to the Type
variable. This condition is usually satisfied by shape files
originally created for GPSmapper software.
If type conversion
table was defined in Step 2, Type
is automatically set to the respective attribute.

Click the Finish
button when the last step is finished.
In this case,
imported map has four types of lines: 3 types as defined in the Step
2 and the 4th (default) type for rest of the lines,
which were left with the undefined type.

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