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TgdbData


Unit:SDL_geodb
Class:TGeoDB
Declaration:
TgdbData = record
  ItemId     : longint;
  Name       : TgdbName;
  Altitude   : single;
  ClassFlag  : byte;
  Tag        : longint;
  BlobOffset : longint;
  Date       : TDateTime;
  StateFlag  : longint;
  LatLow     : single;
  LatHigh    : single;
  LongLow    : single;
  LongHigh   : single;
  case ItemKind: TgdbItem of
   gitBorder,
     gitLake,
     gitCity,
     gitRoad,
    gitRoute,
    gitRiver : (NumPoints  : integer;
                Closed     : boolean);
     gitBLOB : (Size       : longint);
end;

The type declaration TgdbData defines a single data record in the database. The variables declared in TgdbData have the following meaning:

ItemId The variable ItemId is a unique serial number. See Database Item IDs for details.
Name The name of the item (e.g. a city, or a country). In the case of a BLOB (ItemKind = gitBLOB) the name holds the file name of the BLOB.
Altitude Specifies the altitude of the item.
ClassFlag Specifies the class the database entry belongs to. The user may define any class number except 255, since this is used by the search functions as a placeholder for undefined class numbers.
Tag Can be set by the user - it is not used by the database system. The tag is typically used to extend the database functionality.
LatLow, LatHigh Contains the lowest and the highest latitude of all polygon points of the database entry. If an entry does not have any extents, both the low and the high latitude should be set to the same value.
LongLow, LongHigh Contains the lowest and the highest longitude of all polygon points of the database entry. If an entry does not have any extents, both the low and the high longitude should be set to the same value.
Date The date of creation/modification of the database entry.
StateFlag The state of the database entry.
ItemKind The type of database entry. See TgdbItem for details.
BlobOffset File offset of additional data stored in the file *.gdd as binary large object (BLOB). A value of -1 indicates that there is no BLOB attached to this item.
NumPoints Number of polygon points. NumPoints is only valid if ItemKind is set to one of the following values: gitBorder, gitRiver, gitRoad, gitCity, or gitLake.
Closed This flag indicates whether a polygon is closed or not.
Size The size of the BLOB structure in bytes.



Last Update: 2012-Oct-20