Smallworld 4 Reader/Writer

Transcription

1 FME Readers and Writers 2013 SP2 Smallworld 4 Reader/Writer This chapter explains how FME reads and writes data to a Smallworld database. Format Notes This format is supported only by the FME Smallworld Edition. This format must only be used with Smallworld FME Translators and Smallworld 4.2 (or Smallworld 4.2 TSB). You purchase these products separately from GE Energy. The Smallworld interface requires a Smallworld FME Connection Service to be running. Configuring the service is beyond the scope of this document; however, it is described in the GE Energy document Smallworld FME Translators Reference. The GE Energy Smallworld 4 format shipped with FME 2010 and 2011 is supported only for Smallworld sessions based on Smallworld Core Spatial Technology version 4.2. For Smallworld sessions based on Smallworld Core version 3.3, use the GE Smallworld or Smallworld (ACP) format. Overview FME communicates with a Smallworld session through a Smallworld FME connection service controlled by the Smallworld process. To communicate with a Smallworld session, you need to specify: the name, or IP address, of the computer hosting the Smallworld FME connection service the TCP port number on which the service is running on that computer the username and password for accessing the Smallworld database Currently, FME is capable of transferring the following physical, logical, geometrical, and join attribute types to and from Smallworld: character strings (ds_charci_vec, ds_chari_vec, etc.) floating point numbers (ds_float, etc.) integers (ds_int, etc.) Boolean (ds_bool) vectors of float (ds_float), integer (ds_int), Boolean (ds_bool) points chains, with line, arc, circle, spline, and ellipse sectors areas text features date (ds_date)

2 Smallworld 4 Reader/Writer text joins created for variable length text (defined as text_id) join fields created for 1:n or 0:n join relationships Support for Different Versions of Smallworld Smallworld 4.2 and Translators Suite Smallworld Translators Suite 4.2.2, which is compatible with Smallworld 4.2 or Smallworld 4.2 TSB, ships with updated DLL and FMF files for use with FME. The version DLL file is compatible with FME 2010, FME 2011, and FME After completing the Smallworld Translators Suite installation, the files are located in the folder fme422\etc\x86: sworldswaf.dll copy this to the fme installation folder sworldswaf.fmf copy this to the folder fme\metafile Smallworld 4.2 and Translators Suite Smallworld Translators Suite uses the DLL file shipped with Smallworld 4.1. See below for details. Smallworld 4.1 If you are using Smallworld 4.1, you will have to replace the Smallworld 4 DLL files with the following Smallworld 4.1 DLL files located in the default FME Installation directory (you can also copy the files from ftp://ftp.safe.com/fme/smallworld/sworld41dll.zip): sworldswaf40.dll sworldswaf41.dll sworldswaf.dll (identical to sworldswaf40.dll) Smallworld SWAF Quick Facts About Quick Facts Tables Format Type Identifier Reader/Writer Licensing Level Dependencies Dataset Type Feature Type Typical File Extensions Automated Translation Support User-Defined Attributes Coordinate System Support SWORLDSWAF Both FME Smallworld Edition See Format Notes Database Class name Not applicable No Yes No

3 FME Readers and Writers 2013 SP2 Generic Color Support Spatial Index Schema Required Transaction Support Geometry Type No Never Yes No sworld_geom_type Geometry Support Geometry Supported? Geometry Supported? aggregate yes point yes circles yes polygon yes circular arc yes raster no donut polygon yes solid no elliptical arc yes surface no ellipses yes text yes line yes z values yes none yes Reader Overview The Smallworld 4 Reader requires no configuration in addition to the standard configuration keywords mentioned above. When invoked, the reader will connect to the Smallworld FME connection service and begin downloading features. Each feature read from Smallworld will be written in the form described under the heading Feature Representation. Smallworld 4 Reader Parameters Database Connection FME communication with a Smallworld database is controlled by a Smallworld FME server. The connection is to a pre-set alternative in the Smallworld database and for the default Application Configuration File (ACE) the ACE determines which fields are visible in FME Workbench. An administrator may have configured the connection to restrict access to specific datasets, tables, and fields. For details about setting up and starting the Smallworld server, see the GE Energy document Smallworld FME Translator Reference. TICS Server Host The URL of the computer on which the Smallworld FME server is running. For example, if the server is running on the same computer:

4 Smallworld 4 Reader/Writer localhost The value given here is transferred to the Dataset field in the Add Reader dialog box; for example, as: localhost:30000 TICS Server Port The port number on which the Smallworld FME Server listens for FME requests. For example: If left blank, this defaults to The value given here is transferred to the Dataset field in the Add Reader dialog box; for example, as: localhost:30000 Service This field has a default setting of FME. This is not normally changed. Username and Password The Smallworld username of the user requiring access to the Smallworld database. The Smallworld FME server will authenticate the username and password. The permissions of the given user account will control the datasets and tables to which you have access. Constraints Table List Click the Browse button to select the tables to read from. The list of tables includes only the tables you are authorized to see. If an alternative is specified, then the list includes only the tables available in that alternative. The name of each table is prefixed with the dataset name. To filter a long list of tables, enter the first few letters of the table name in the Filter field. Alternative The name of the alternative in the Smallworld database to read from (for example, test), or the default FME alternative if left blank. You cannot read from an alternative if there are uncommitted changes. The data which is read will include all changes made in that alternative. If reading from multiple datasets, the alternative must exist in each of the datasets. Reader Directives The directives that are processed by the Smallworld 4 reader are listed in the sections that follow. The Reader keyword is SWORLDSWAF_

5 FME Readers and Writers 2013 SP2 ALTERNATIVE This directive specifies the alternative to read from in the Smallworld database. The default alternative is used if no value is specified. Optional Values ALTERNATIVE, fme_exports BASELINE_ALTERNATIVE See EXPORT_CHANGES. BASELINE_CHECKPOINT See EXPORT_CHANGES. CHECKPOINT The name of the Smallworld checkpoint to read from. Optional EXPORT_CHANGES Specifies that only the differences between the alternative or checkpoint specified in the ALTERNATIVE or CHECKPOINT directives and those specified in BASELINE_ ALTERNATIVE or BASELINE_CHECKPOINT are read. For example: EXPORT_CHANGES,YES,BASELINE_ALTERNATIVE, fme_exports,baseline_ CHECKPOINT,0, Where BASELINE_ALTERNATIVE is the name of the Smallworld alternative to use as the base for comparison and BASELINE_CHECKPOINT is not used. Optional EXPOSE_INTERNAL_TABLES Specifies that internal tables as configured by the Smallworld administrator are included in the list of tables. Optional

6 Smallworld 4 Reader/Writer _MERGE_SCHEMAS This directive determines the number of feature types to be displayed in Workbench. Required Values YES specifies that all features types in the Smallworld dataset are merged into one single feature type for display in Workbench. NO specifies that one feature type will be displayed in Workbench for every feature type in the dataset PORT The port number on which the Smallworld FME connection service listens for FME requests. If left blank, the port number defaults to Optional QUERY Specifies a query for filtering data. Only data from the tables specified in the query is read; however, schema will be created for all the tables specified in the TABLELIST directive. For example, this selects records from the Hotel table where Name >= "h": QUERY,Hotel<lt>space<gt><lt>lf<gt>where<lt>space<gt>Name<lt>space<gt><lt>gt<gt>=<lt> space<gt><lt>quote<gt>h<lt>quote<gt> Optional SEARCH_ENVELOPE See USE_SEARCH_ENVELOPE. SERVER The URL of the computer on which the Smallworld FME connection service is running. Required SERVICE The default value for this directive is FME. This is not normally changed

7 FME Readers and Writers 2013 SP2 Required TABLELIST This directive specifies the Smallworld database tables to read from, as a spaceseparated list. Mapping File Syntax TABLELIST,<DatasetName>.<TableName><space><DatasetName>.<TableName> For example: gis.office<space>gis.office_location<space>gis.office_annotation Required USE_SEARCH_ENVELOPE This directive specifies whether all features are read or just those that fall inside or overlap the specified bounds. The directive is set to NO if all features are to be read. For example: USE_SEARCH_ENVELOPE,YES,SEARCH_ENVELOPE_MINX, ,SEARCH_ ENVELOPE_MAXY, , SEARCH_ENVELOPE_MAXX, ,SEARCH_ ENVELOPE_MINY, Where: SEARCH_ENVELOPE_MINX, SEARCH_ENVELOPE_MINY, SEARCH_ENVELOPE_MAXX, SEARCH_ENVELOPE_MAXY specify the spatial extent of the features to be read. The values are in the format of the coordinate system set for the Smallworld database, or 0 if the USE_SEARCH_ENVELOPE directive is set to NO. Optional USER_NAME, PASSWORD Specifies the user account to use when connecting to the Smallworld database. Required Writer Overview The Smallworld writer must be given the definitions of the Smallworld objects before it may start writing them out. This is accomplished by importing feature type definitions from the Smallworld database

8 Smallworld 4 Reader/Writer The attribute types in the object definitions come from the following set: Attribute Type char(<len>) Description Character string with a specified maximum length. Note: Notes: Use char(255) for join fields. Use char(65535) for Text join fields. char float float(<len>) int int(<len>) boolean boolean(<len>) enum(<enum name>) enum Character string with a default maximum length (currently set to 254). This type should be used only for testing purposes, and not for production mapping files; for most cases, use the char(<len>) form above. Floating point number. Vector of floating point numbers, with a length of <len> values. These are represented in FME by a commaseparated list. This list must have exactly <len> values in it. If the feature being written has attributes named <attribute name>{0}, <attribute_name>{1}, etc. then these values will take precedence over the commaseparated list in <attribute name>. Integer Vector of integers, with a length of <len> values. These are represented in FME by a comma-separated list. This list must have exactly <len> values in it. If the feature being written has attributes named <attribute name>{0}, <attribute_name>{1}, etc. then these values will take precedence over the commaseparated list in <attribute name>. Boolean value, represented by 1 for true or 0 for false. Vector of Booleans, with a length of <len> values. These will be represented in FME by a comma-separated list. This list must have exactly <len> values in it. This is an enumerated attribute. In FME, enumerated attributes simply contain a string with the symbolic value of the enumerated type. An enumerated attribute must contain a valid value when being sent to Smallworld. Alternate form of enum(<enum name>) which matches any enumerated type. The values for these attributes must be valid for the actual Smallworld attribute to which they map

9 FME Readers and Writers 2013 SP2 Attribute Type date fme_db_operation sworld_point sworld_chain sworld_area sworld_text sworld_join_names Description Date and time attribute. The value of <attribute name> is in the form year, month, day: YYYYMMDD. If an attribute named <attribute name>.full is defined on the feature, it has the form year, month, day, hour, minute, second YYYYMMDDhhmmss and will be used instead of <attribute name>. The type of operation when writing to a Smallworld database: INSERT, UPDATE, or DELETE. A geometrical attribute defining a point, scale, and orientation or rotation. A geometrical attribute defined by a series of linear parts or sectors. A geometrical attribute defined by a series of linear parts. The area completely contained by the joined linear parts is the geometry of the attribute. A text attribute containing a position, a text string, height, justification, and orientation or rotation. Dummy attribute used to set the name of the join field(s) in the feature type. For a single join field, takes the format: <join name> For a feature type with multiple join fields, takes the format: <feature>.<join name>,<feature>.<join name> sworld_join_values Dummy attribute used to temporarily hold the unique IDs from the source data needed to form the join. A Smallworld object may contain zero or more geometrical attributes and each of these may be defined or may be left unset. The Geometry Representation section explains how FME geometry is mapped onto geometric attributes such as sworld_ point, sworld_chain, sworld_text, and sworld_area. Smallworld 4 Writer Parameters Database Connection FME communication with a Smallworld database is controlled by a Smallworld FME server. The connection is to a predefined Smallworld database alternative. An administrator may have configured the connection to restrict access to specific datasets, tables and fields. For details of setting up and starting the Smallworld server, see the GE Energy document Smallworld FME Translator Reference

10 Smallworld 4 Reader/Writer Server Host The URL of the computer on which the Smallworld FME server is running. For example, if the server is running on the same computer: localhost The value given here is transferred to the Dataset field in the Add Writer dialog box; for example, as: localhost:30000 Server Port The port number on which the Smallworld FME Server listens for FME requests. For example: If left blank, this defaults to The value given here is transferred to the Dataset field in the Add Writer dialog box; for example, as: localhost:30000 Service This field has a default setting of FME. This is not normally changed. Username and Password The Smallworld username of the user requiring access to the Smallworld database. The Smallworld FME server will authenticate the username and password. The permissions of the given user account will control the datasets and tables to which you have access. Constraints Expose Internal Tables You cannot use this option when configuring a Smallworld 4 Writer. Table List Click the Browse button to select the tables to write to. The list of tables includes only the tables you are authorized to see. If an alternative is specified, then the list includes only the tables available in that alternative. The name of each table is prefixed with the dataset name. To filter a long list of tables, enter the first few letters of the table name in the Filter field. Alternative The name of the alternative in the Smallworld database to write to (for example, test), or the default FME alternative if left blank. You cannot write to an alternative if there are uncommitted changes. If writing to multiple datasets, the alternative must exist in each of the datasets

11 FME Readers and Writers 2013 SP2 Checkpoint The name of the Smallworld checkpoint for the specified alternative. You cannot continue if the alternative has uncommitted changes. If you are writing to multiple datasets, the checkpoint must exist in each dataset. If the checkpoint does not exist in one of the datasets, then set up a separate writer for that dataset. WHERE Clause You can filter the data from specific tables by using a Smallworld query. Only data from the tables in the where clause will be written; any other tables specified in the Table List will be ignored. To enter a query, click the Browse button to display the WHERE Clause dialog box, and then enter the query either by typing or by pasting a query script that you created in Smallworld. Click OK. Note You must always precede each table in the query with the dataset name, using the format: [<dataset_name>]<table_name> For example: [Gis]Road where Name = "Burleigh Street", plus [Gis] Pub/Restaurant where count( Access Roads ) > 0 If you are unfamiliar with the predicate language, you may prefer to create a Design View(script) query in Smallworld and then copy the query (taking care to remove any end-of-line characters (/n) that may be inserted when you paste. Note: You cannot use a WHERE clause and Export Changes from Baseline. Export Changes from Baseline To write data that is just the differences between the current alternative or checkpoint specified in the Constraints area and another alternative or checkpoint, select the Export Changes from Baseline checkbox and then enter the version of the data you want to use as the baseline. Note: You cannot use a WHERE clause and Export Changes from Baseline. Alternative The name of the Smallworld alternative to use as the base for comparison. The data

12 Smallworld 4 Reader/Writer that is written will be the changes between this alternative and the current alternative or checkpoint. Checkpoint The name of the Smallworld checkpoint to use as the base for comparison. The data that is written will be the changes between this checkpoint and the current alternative or checkpoint. Writer Directives By default, the <WriterKeyword> for the Smallworld writer is SWORLDSWAF_1. Feature Representation Smallworld objects may have more than one geometry, and in fact commonly do. Users may control whether there is a one-to-one correspondence between FME features and Smallworld objects (the default behavior for the reader), or if there is one FME feature for each geometry attribute within a Smallworld object (the default behavior for the writer). However, users can change the reader to create one FME feature for each geometry attribute by passing FME NOFACTORY as a parameter. When there is a one-to-one correspondence, the feature type of the FME feature is the concatenation of the dataset name in the Smallworld database and the external name given to the Smallworld object definition. Each attribute in the Smallworld object is represented by one or, for geometric attributes, several attributes on the corresponding FME feature. The names of physical attributes in FME are identical to those in Smallworld. The sections below describe this representation, which is also used exclusively by the writer. The reader is most often used in a mode where there is one FME feature for each geometry attribute in the Smallworld object. In those cases, the feature representation is as described below, without the sworld_geometry{<n>} prefix. FME uses the representations shown in the following table for the values of Smallworld physical attributes. Vectors, multiple joins, and dates have special representation in the feature s attributes and are discussed under the headings Vectors and Multiple Join Attributes, Foreign Key Attributes and Date and Time Attributes found later in this chapter. Geometric attributes are discussed under the heading Geometry Representation. Physical Attribute Type character string Representation (by examples) Bourbon Street integer 123 float boolean

13 FME Readers and Writers 2013 SP2 Physical Attribute Type enumerated type Representation (by examples) toll_highway integer vector 123,345,445,111 float vector ,123.33, text join Bourbon Street is a famous and historic street that spans the length of the French Quarter in New Orleans, Louisiana. foreign key field single join field Note: Foreign key fields that are character strings have a 0 length; you will need to assign a width to the attribute. multiple join field , date field Vectors and Multiple Join Attributes Smallworld fields that can contain a collection of values integer and float vectors are represented in two forms on the FME feature. The first is the comma-separated list depicted in the preceding table. For vectors, this table always contains exactly as many elements as are defined for the vector in the table s schema. The second representation of multiple-value fields is as a list of attributes. When reading a vector or multiple join field, the Smallworld reader creates attributes <attrname>{0}, <attrname>{1}, etc. Each <attrname>{n} attribute contains a single element from the comma-separated list. When writing to Smallworld, the writer first looks for an attribute named <attrname>{0} on the feature being written. If this attribute exists, the writer will ignore the contents of the comma-separated value attribute and use the values of <attrname>{0}, <attrname>{1}, etc. to define the output field values instead. Foreign Key Attributes (1:n and 1:n Heterogeneous Joins) You can write records that have a foreign key relationship provided that you can map the join field in the feature type at the child end of the relationship to the join field at the parent end. The Writer will preserve values in text-based join fields but will overwrite foreign key values that are automatically generated integers, such as sys_ id fields. A workaround is provided for the case where the feature type has a single system-generated ID field of type int

14 Smallworld 4 Reader/Writer In order to set up the feature types correctly for your Smallworld database, we recommend that you first import the object definitions from the Smallworld database. See the GE Energy Smallworld FME Translator Reference for an example. Writing records for the child feature type Where the feature type is the child end of a foreign key relationship, there is a field for the parent record ID which forms the join. This field takes the name of the join field appended with!fk1. For example, if the join field is placement, then the key field is: placement!fk1 Where the parent end of this type of join is heterogeneous (that is, may be one of several different object types), then you also need to write the ID of the table containing the parent records the table ID will be part of the join data. This field takes the name of the join field appended with!tid. For example: placement!tid See the GE Energy Smallworld FME Translator Reference for an example. Writing records for the parent feature type The following information only applies when the foreign key relationship relies on a single system-generated ID of type int (as is the case for the sys_id field type). You cannot write records that have multiple system-generated integer values. New records in Smallworld are typically assigned an automatically-generated system ID on insertion, which will be unknown to FME. The following step is therefore necessary to temporarily hold the ID of each parent record from the source data and then match it to the join field in the newly inserted parent records in the Smallworld database. To do this you need to set up the following user attributes: sworld_join_names : use a constant to map this to the name of the Smallworld join field in the parent feature type. sworld_join_values : map this to the field in the source data that holds the parent ID, using the format <feature name>.<join field name>. For example, if a Smallworld Park object has foreign key relationships to child objects Seat, Kiosk and Gate where placement are the join field names, then you would set sworld_join_ names to the following: seat.placement,kiosk.placement,gate.placement See the GE Energy Smallworld FME Translator Reference for an example. Date and Time Attributes When a date field is read by the Smallworld reader, two attributes are set in the FME feature. The first attribute is simply the name of the attribute, as specified by YYYYMMDD. This is compatible with all other FME dates

15 FME Readers and Writers 2013 SP2 The second attribute has a suffix of.full and is of the form YYYYMMDDHHMMSS. It specifies the date and the time, with the time portion specified using the 24-hour clock. For example, if a date field called update_time is read, the following attributes will be set in the retrieved FME feature: update_time = update_time.full= When writing to Smallworld, the writer looks for both attributes. Either may be in the form of YYYYMMDD or YYYYMMDDHHMMSS. If both attributes are specified, then the value specified in update_time.full is used. Geometry Representation There are two aspects to the representation of Smallworld geometries within FME: the representation of an individual geometric attribute point, text, chain, or area the handling of multiple geometric attributes on a single feature Multiple Geometric Attributes Smallworld objects can have very complex geometries associated with them. A single object can have any number of geometries of varying geometric types associated with it. To represent this in FME, it is necessary to use aggregates of geometry. Aggregates contain a list of geometric components. For certain geometric attribute types chains and areas it is also possible for a component of the aggregate to be an aggregate itself. The handling of such structured geometry is discussed below, in the description of the representation of chain geometries. In general, however, when a feature has an aggregate geometry, each component of the aggregate relates to a single geometric attribute. In order to correlate each component of an aggregate with a particular geometric attribute, additional attribution is given to the FME feature, as follows: sworld_geometry{<n>}.sworld_name Name of corresponding Smallworld geometric attribute for component <n> of the aggregate. sworld_geometry{<n>}.sworld_type Type of corresponding Smallworld attribute for component <n> of aggregate. Legal values are: sworld_chain, sworld_area, sworld_point, and sworld_text. The components of the aggregate are numbered starting at 0. Therefore, if an FME feature is representing a Smallworld object with two defined geometric attributes, its geometry will be an aggregate with two components; each component will be the geometry for one of the geometric attributes on the Smallworld object. To identify the geometries to FME, the feature must also contain the following attributes: sworld_geometry{0}.sworld_name sworld_geometry{0}.sworld_type attrname1 geomtype

16 Smallworld 4 Reader/Writer sworld_geometry{1}.sworld_name sworld_geometry{1}.sworld_type attrname2 geomtype2 The count and ordering of the geometries within the aggregate must match the count and ordering of the sworld_geometry{} attribute lists exactly. There is no ordering of geometries implied by attribute naming or position within the SWORLD_DEF lines. Certain geometric types require additional attributes. These are discussed in depth under the heading Individual Geometric Attribute Representation. If a particular geometric attribute requires additional information, it must be provided in an attribute whose name begins with the correct sworld_geometry{} specification. For example, if the first geometric attribute requires an orientation, the FME feature must contain an attribute like: sworld_geometry{0}.sworld_orientation In its simplest case, a Smallworld object has only a single geometric attribute or the Smallworld writer supplies only a single geometric attribute to an object. In these cases, it is possible for the FME feature to contain a single, non-aggregate geometry for the object. However, there must still be a complete accompanying set of sworld_ geometry{0}.xxx attributes defined on the feature. When reading data from Smallworld, by default FME flattens the geometry into a single geometry per feature, based on each geometry attribute in the original Smallworld feature. Internally, the reader employs the SmallworldGeometryFactory to do this work, which simplifies the mapping process for users. In some situations, the aggregate model may be useful, and in those cases, the reader can return an aggregate representation. The SmallworldGeometryFactory is fully described in the FME Functions and Factories manual. Individual Geometric Attribute Representation There are four basic geometric types handled by FME: point, text, chain, and area. Each of these is discussed below. The aggregate referred to in the text below is described in the previous section. Point Geometries In addition to the basic (x,y[,z]) location, a Smallworld point has the following attributes defined: Attribute Name Meaning Default sworld_orientation Rotation of the point's symbol, expressed in degrees counter-clockwise. 0.0 sworld_scale Magnification factor of the symbol

17 FME Readers and Writers 2013 SP2 The geometric type for a point is sworld_point. For example, the following FME feature is used in a Smallworld application to represent a fire hydrant whose hose attaches on the northeast side: Feature type: hydrant FME geometry: Aggregate containing one point (123.4,567.8) Attributes: color gold street Knowles Ave sworld_geometry{0}.sworld_name position sworld_geometry{0}.sworld_type sworld_point sworld_geometry{0}.sworld_orientation 45.0 sworld_geometry{0}.sworld_scale 1.0 Text Geometries Text geometry is commonly used to provide annotation in a Smallworld application. An FME feature representing annotation has a point geometry and the following geometric attributes: Attribute Name Meaning Default sworld_text_string The textual part of the annotation. " " sworld_text_height sworld_orientation sworld_vert_just sworld_horiz_just The annotation text height scaling factor. The scaling factor of the text height defined in the Smallworld style. The rotation of the text, in degrees counter-clockwise. Vertical justification of the text about its location point. The value is an integer in the range See the discussion following this table for more information. Vertical justification of the text about its location point. The value is an integer in the range See the discussion following this table for more information The geometric type for a piece of annotation is sworld_text. Justification of text in a Smallworld application is performed on a five by five grid, with the lower left corner being (1,1), and the upper right corner being (5,5). Each horizontal or vertical justification value is a discrete position within the grid. The position within the grid is the location of the text's point geometry with respect to the text string

18 Smallworld 4 Reader/Writer Chain Geometries Chains and areas are somewhat more complex than point and text geometries. The complication comes from two aspects of the Smallworld geometries: A single chain or area is comprised of one or more sectors, which join together end-to-end to make the chain. Each sector can be one of four different types: line string, circular arc, circle, or ellipse. The first problem is handled once again by using FME's aggregate geometries. A chain or area's component of the feature's aggregate geometry is itself an aggregate. This can be somewhat confusing, but it is a very powerful and necessary way to represent Smallworld data. For example, suppose a chain is a rope of three sectors: two line strings connected by an arc. This would be represented by an aggregate geometry with three parts: the first line string a circular arc, whose first point is the same as the last point of the previous line string the second line string, whose first point is the same as the arc's last point Of course, there must be a way to tell FME how to interpret each sector. Like the multiple geometric attributes, this is handled by FME's list attributes. For this example, there must be three attributes one for each sector defined on the FME feature. These attributes are all located below sworld_geometry{x}, just like all other geometric attributes. If this chain is the second component of an aggregate geometry, the FME feature will contain the following attributes and values to describe the chain: Attribute Name sworld_geometry{1}.sworld_sector{0}.sworld_sector_type sworld_geometry{1}.sworld_sector{1}.sworld_sector_type sworld_geometry{1}.sworld_sector{2}.sworld_sector_type Value line arc line The arc also requires some additional attributes to describe it. These attributes are: Attribute Name Value sworld_geometry{1}.sworld_sector{1}.sworld_radius sworld_geometry{1}.sworld_sector{1}.sworld_start_angle sworld_geometry{1}.sworld_sector{2}.sworld_sweep_angle The building of these complex geometries in FME mapping files will require a number of AggregateFactories. The extraction of geometries will require a number of DeaggregateFactories

19 FME Readers and Writers 2013 SP2 As for the aggregates representing multiple geometric aggregates, it is possible that a chain or area can be represented by a single FME line geometry. In this case, the feature given to the Smallworld writer may contain a simple line geometry rather than an aggregate containing a single line. There are six kinds of sectors which may make up a sector rope aggregate for chain and area geometries: line, arc, circle, ellipse, elliptical arc, and spline. The structure of these geometries is described below. Line Sector A line is a simple string of (x,y) or (x,y,z) points. A feature containing a chain or area with a line sector must have the following attribute defined: sworld_geometry{<m>}.sworld_sector{<n>}.sector_type sworld_line where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry. No additional attributes are required to define a line sector. Arc Sector An arc sector represents a portion of a circle. The arc is defined on the FME feature as a point geometry representing the center of the circle to which the arc belongs, with a number of attributes to describe the arc. The following attribute is defined on an FME feature containing an arc sector: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_sector_type sworld_arc where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry. The following attributes are also defined on arc geometries. The attribute names will appear at the same level as the sector type; for example: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_radius) Attribute Name Meaning Default sworld_radius sworld_start_angle sworld_sweep_angle The radius of the circle containing the arc. The angle in degrees counter-clockwise from due east denoting the position on the circle of the arc's starting point. The length of the arc, measured in counter-clockwise arc degrees. This number may be negative. none none none

20 Smallworld 4 Reader/Writer Elliptical Arc Sector An elliptical arc sector represents a portion of an ellipse. The arc is defined on the FME feature as a point geometry representing the center of the circle to which the arc belongs, with a number of attributes to describe the arc. The following attribute is defined on an FME feature containing an elliptical arc sector: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_sector_type sworld_arc where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry. The following attributes are also defined on arc geometries. The attribute names will appear at the same level as the sector type; for example: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_prim_radius) Attribute Name Meaning Default sworld_prim_radius sworld_sec_radius sworld_orientation sworld_start_angle sworld_sweep_angle Circle Sector The primary radius of the ellipse containing the arc. The secondary radius of the ellipse containing the arc. The orientation of the ellipse's primary axis, measured in degrees counterclockwise from due east. The angle in degrees counter-clockwise (measured relative to the orientation of the ellipse) denoting the position on the circle of the ellipse's starting point. The length of the arc, measured in counter-clockwise arc degrees. This number may be negative. none none none none none A circle sector represents a full circle centered on a specific geographic point. The circle is defined in the FME feature as a point geometry representing the center of the circle, with an additional attribute to specify its radius. The following attribute is defined on an FME feature containing a circle sector: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_sector_type sworld_circle where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry

21 FME Readers and Writers 2013 SP2 The following attribute is also defined on circle geometries. The attribute name will appear at the same level as the sector type, in other words, sworld_geometry{<m>}.sworld_sector{<n>}.sworld_radius) Attribute Name Meaning Default sworld_radius The radius of the circle. none Ellipse Sector An ellipse sector represents a full ellipse centered on a specific geographic point. The ellipse is defined in the FME feature as a point geometry representing the center of the ellipse, with additional attributes to specify its radii and orientation. The following attribute is defined on an FME feature containing an ellipse sector: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_sector_type sworld_ellipse where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry. The following attributes are also defined on ellipse geometries. The attribute names will appear at the same level as the sector type; for example, sworld_geometry{<m>}.sworld_sector{<n>}.sworld_prim_radius) Attribute Name Meaning Default sworld_prim_radius The primary radius of the ellipse. none sworld_sec_radius The secondary radius of the ellipse. none sworld_orientation Spline Sector The orientation of the ellipse's primary axis, measured in degrees counterclockwise from due east. none A spline sector represents Smallworld s rational b-spline geometry. The spline is defined in the FME feature as a line string representing the spline s fit points, and a number of attributes describing the spline s control points and other required data. The following attribute is defined on an FME feature containing a spline sector: sworld_geometry{<m>}.sworld_sector{<n>}.sworld_sector_type sworld_spline where <m> is the index of the chain or area geometry, and <n> is the index of the line sector within the geometry. The following attributes are also defined on spline geometries. The attribute names will appear at the same level as the sector type; for example, sworld_geometry{<m>}.sworld_sector{<n>}.sworld_poly_degree)

22 Smallworld 4 Reader/Writer Attribute Name sworld_poly_degree sworld_spline_type sworld_start_tangent_x sworld_start_tangent_y Meaning The degree of the polynomial used to form the spline. The flag that indicates the type of the spline. It is a bit-wise combination of the following values: 1. CLOSED 2. PERIODIC 4. RATIONAL 8. PLANAR 16. LINEAR The (x,y,z) coordinate of the point that identifies the tangent to the start of the spline. sworld_start_tangent_z sworld_end_tangent_x sworld_end_tangent_y The (x,y,z) coordinate of the point that identifies the tangent to the end of the spline. sworld_end_tangent_z sworld_num_knots sworld_knots sworld_control_x sworld_control_y The number of knots in the spline. The knots of the spline, as a comma-separated list. Comma-separated lists of the x, y, and z control point coordinates. sworld_control_z sworld_control_weights The control point weights, a comma-separated list of the weight values for each control vertex