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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 or export
into other format (Advanced version only).
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 following steps:
- Coordinate System. Selection of projection and datum used for representation of
geographical data in SHP file.
- Types. Assignment of SHP attributes to types (like polyline type)
used by Mapwel and Garmin GPS.
- Enumerated Parameters. Assignment of SHP attributes to object parameters
with limited number of allowed values (like
"Oneway" road parameter) in Mapwel.
- Parameters. Assignment of other SHP attributes representing name, comment,
street name, phone
number and other data to Mapwel data structures.
- Format. Formatting of object name, comment. Selection of
elevation units, etc.
Only the first step (selection of coordinate system) is
obligatory. Next steps are optional, but they are usefull to
transfer information from attributes in a shapefile to
objects in Mapwel. This helps to reduce or completely
eliminate editing of map in Mapwel.
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. This is the most important step in
loading of the shapefile. You have to know coordinate system
of the SHP file. If chosen coordinate system is not the right
one, map will be imported improperly. This information is
often stored in *.PRJ text file enclosed to the shapefiles. If
*.PRJ file is in the same folder as *.SHP file and has the
same name, Mapwel tries to read the georeference data
automatically.
UTM Zone Number, UTM Latitude Band Letter and Planar Distance Units are controls for
definition of additional information for UTM system. UTM Latitude
band letter affects only selection of the hemisphere (northern or southern) when
converting coordinates from UTM to Lat/Lon. Therefore, you can obtain the same
Lat/Lon coordinates for various band letters.
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 by
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.
Use Import roads as routable option to convert
polylines that represent roads to Routable road objects
in Mapwel. Other polylines (like rivers, power line, etc.) are
converted to common Line object. It is possible to make
such conversion later in the work area of Mapwel as well.
However, next tabs allow to assign parameters essential for
routing only when this option is checked.
If Detect intersection nodes option is checked,
program will automatically detect and mark intersections of
routable roads. These intersection nodes are essential for
compilation of routable map. Detection of intersection nodes
can be done also later, with use of main
menu > Routing > Detect Intersections command.

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 attributes to
Mapwel types
You
can use this tab to create 'attribute value-to-Mapwel parameter
value' conversion
table. This table contains only parameters with finite number of
possible values, for example 'Oneway' parameter, which can be
only TRUE (checked) or FALSE (unchecked). Shapefile attribute
value is mapped to the Mapwel parameter value.
The first column contains such parameters and all their
possible values, for example: Max. Speed:10 km/h, Max. Speed:
20 km/h, etc. It is not possible to edit this column.
However, user can select shapefile attribute into the next
column and its value to 3rd or 4th column. In below example Max.
Speed is set to 130 km/h in Mapwel for all objects
that have TYPE attribute set to HWY in the
shapefile.
Selection of attribute or its value is easy: just click on
respective table cell and select required item from the pop-up
menu that appears. You should define the attribute first and
the value(s) next, because values list is generated according
to selected attribute. It is not necessarry to fill-in all
cells in the table. Set only those lines of table that you
need to.
Shapefile can contain any attributes with any values and this
table allows to map them onto parameters of individual objects
in Mapwel. There are two columns (Value 1 and Value 2) of attribute values for case that you need to map two attribute
values to the same Mapwel parameter value. For example, you
may need to map TYPE: TRAIL and TYPE: WALK from shapefile
to the same Mapwel parameter value Max. Speed: 10 km/h. Note:
speed levels are set to km/h or mi/h according to units
selected in main menu > Edit >
Preferences.

Step 4 - Assignment of other SHP attributes to Mapwel data structures
The fourth tab allows to assign attributes with
virtually infinite number of values (like text labels, for
example) to Mapwel object.

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 polygon, polyline 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.
Left Side and Right Side controls
allow to define house numbering along the street for the
Routable Road objects. Type of numbering (None, Even, Odd or
All) can be set on the previous tab.
Step 5 - Fields formatting

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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