13.2.8 Conditional Symbology Procedure QUAPNT02
Quality of position of point and area objects (S-57) Conditional Symbology Procedure for additional symbology for point and area objects when positional accuracy is low. (Note that this is called as a sub-procedure by OBSTRNnn, QUAPOSnn, SLCONSnn, WRECKSnn).
Applies to: S-57 Object Class "Land area" (LNDARE) as point;
S-57 Object Class "Obstruction" (OBSTRN) as point and area;
S-57 Object Class "Shoreline construction" (SLCONS) as point;
S-57 Object Class "Wrecks" (WRECKS) as point and area.
S-57 Object Class "Under water rock" (UWTROC) as point.
Spatial Object(s): Point, Area.
Attribute(s) used: Spatial attribute QUAPOS
Parameter(s): Object to be symbolized from SENC.
User Parameters: View low accuracy symbols.
Defaults: Symbolization given by the look-up table:
Display Priority given by look-up table;
OVERRADAR priority given by look-up table;
Display Category given by look-up table;
Viewing Group given by look-up table
Remarks: The attribute QUAPOS, which identifies low positional accuracy, is attached only to the spatial component(s) of an object.
This procedure checks whether the mariner has requested that the symbol SY(LOWACC01) is to be shown; retrieves any QUAPOS attributes; and returns the appropriate symbols to the calling procedure.
Figure 18 QUAPNT02 conditional symbology sub-procedure
Entry point
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Entry from the calling conditional procedure.
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Get the Calling Object
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Get the object which is calling this procedure.
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ACCURATE=TRUE
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Set local variable 'ACCURATE' equal to true.
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Show Low Accuracy symbols?
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Has the mariner chosen to view the low accuracy symbols (LOWACC01) (i.e. viewing group equals 31011)?
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return
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If ‘No’, return to the calling procedure with the message that the low accuracy symbol is not required!
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Loop for each spatial component
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For each spatial component of the object perform this loop
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ACCURATE == FALSE?
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Is the local variable 'ACCURATE' set to 'FALSE?
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return
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If ‘No’, return to the calling procedure with the message that the low accuracy symbol is not required.
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SELECT = 'LOWACC01'
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Select the 'Low Accuracy' symbol 'LOWACC01' Return to the calling procedure.
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return
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Return to the calling procedure with the message that the low accuracy symbol is to be shown, also return the selected symbol ‘LOWACC01’.
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Figure 19 Loop for each spatial component
Loop entry point
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For each spatial component of the object, perform this loop:
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Get the Spatial Component
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Get the next spatial component of the calling object.
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Get 'QUAPOS'
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Get the value of the attribute 'Quality of position' (QUAPOS) of the current spatial component
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Has value ('QUAPOS')?
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Is the value of the attribute 'QUAPOS' given?
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continue
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If ‘No’, go to the next spatial component of the calling object.
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'QUAPOS' == 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9?
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Does the value of the attribute 'QUAPOS' equal to one of the following values: '2', '3', '4', '5', '6', '7', '8' or '9'?
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continue
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If ‘No’, go to the next spatial component of the calling object.
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ACCURATE=FALSE
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Set local variable 'ACCURATE'='FALSE'.
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break
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Loop by spatial components
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