IGDS Feature Representation (Format Attributes)

In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Attributes), this format adds the format-specific attributes described in this section.

Special FME feature attributes are used to hold IGDS element parameters:

The IGDS writer will use these attribute values as it fills in an element structure during output.
The IGDS reader will set these attributes in the FME feature it creates for each element it reads.

The following table maps the IGDS element type number to its corresponding FME feature igds_type attribute value that is used by the IGDS reader and writer.

IGDS Element Type	FME igds_type
2, Cell header	igds_cell
3, Line 4, Line string 12, Complex string	igds_point
3, Line 4, Line string 11, Curve 12, Complex string 27, B-Spline curve 33, Dimension 36, Multi-line	igds_line
6, Shape 14, Complex shape	igds_shape
7, Text node	igds_text_node
11, Curve 12, Complex string	igds_curve
12, Complex string	igds_complex_string
14, Complex shape	igds_complex_shape
15, Ellipse	igds_ellipse
16, Arc	igds_arc
17, Text 37, Tag attribute	igds_text
7, Text node 17, Text	igds_multi_text
2, Cell header	igds_solid
35, Shared cell header	igds_shared_cell
19, Solid (V8 only) 23, Cone	igds_3d_solid
100, Reference attachment (V8 only)	igds_xref
39, DgnStore header (V8 only)	igds_xfmstore
105, Mesh	igds_mesh
106, Polygon collection	igds_polygon_collection
107, Non-geometric collection	igds_nongeom_collection

FME considers the IGDS level to be the FME feature type of an IGDS feature. Each IGDS element, regardless of its geometry type, shares a number of other parameters, as described in the following table.

When writing elements, igds_type has precedence over the igds_element_type, unless there is more than one element type for a given type. For example, for igds_line the igds_element_type can be used to force the element to be a type 4 line element, even if there are only 2 vertices on the line (that is, it should really be a type 3 element).

Attribute Name	Information	Contents
igds_basename		The base filename (without extension) of the design file the elements were read from. This attribute is ignored by the writer. Range: ASCII filename
igds_color		The element’s color setting. This is the element’s color index into the color table stored in the design file. This attribute will be overridden by the igds_symbology value. Range: 0..255 Default: 0
igds_color.red	Reader only	The element’s red color intensity, as determined by looking up the element’s color index in the color table. Range: 0..255
igds_color.green	Reader only	The element’s green color intensity, as determined by looking up the element’s color index in the color table. Range: 0..255
igds_color.blue	Reader only	The element’s blue color intensity, as determined by looking up the element’s color index in the color table. Range: 0..255
igds_color_set_bylevel	Version 8	Set to Yes if the element’s color is set by level; otherwise it is set to No. If it is set to Yes, the writer sets the element’s property to pick the color from the level it is on. Range: Yes/No Default: No default
igds_class		The element’s class. Sample values: PRIMARY = 0 COMPONENT = 1 CONSTRUCTION = 2 DIMENSION = 3 PRIMARY_RULE = 4 LINEAR_PATTERNED = 5 CONSTRUCTION_RULE = 6 Range: 0..15 Default: 0
igds_element_type		The numeric Design file element type code of the element. When writing to a Design file, the igds_type field overrides this attribute. This attribute will be overridden by the igds_type value. Range: See the Overview section. Default: No default
igds_graphic_group		The element’s graphic group number. Range: 0..65535 Default: 0 Tip: By using a common value for graphic group value, several otherwise separate elements may be tied together into a logical super-element for later processing by application programs.
igds_hole	Writer only	If present, it sets the “hole” bit on the element it is creating. Range: string Default: No default
igds_level	There is no upper limit on levels for Version 8 DGN files.	The IGDS level of the feature. The value of this attribute is the same as the feature type. The Writer will use the value of this attribute if the feature's type cannot be converted into a valid IGDS level. When writing, this will assign the created element to the specified level. Levels found in the seed file are preferred. For cells, which are defined in a cell library, this does not change the level to which the cell member elements are assigned. For more information, see Writer Feature Type Parameters. Range: 0..64 Default: No default
igds_level_comment	Reader only	The comment associated with the level from which the element originated. Range: String Default: No default
igds_level_group_id	Reader only Does not exist for Version 8 DGN files.	The group identification of the level from which the element originated. Range: String Default: No default
igds_level_name	For writing to Version 8 DGN files only, this may be used instead of the feature_type to set the level name.	During reading this represents the name of the level from which the element originated. For V8 writing, if the igds_level is not set or found in the seed file, this will be used to try to match a level in the seed file. For more information, see Writer Feature Type Parameters. Range: String Default: No default
igds_snappable		The element’s snappability. Range: Yes or No Default: Yes
igds_style	For Version 8 DGN files: If this value is negative, it represents a custom line style.	The element’s line style. This attribute will be overridden by the igds_symbology value. Range: 0..7, negative integers Default: 0
igds_style_set_bylevel	Version 8	Set to Yes if the element’s style is set by level; otherwise it is set to No. If it is set to Yes, the writer sets the element’s property to pick the style from the level it is on. Range: Yes/No Default: No default
igds_style_name	Version 8. This value may be used by the writer to check that the (custom) line style definition found in the seed file for the style is the intended line style.	The name of the element's line style. This attribute is used by the reader to provide the name of the style used in the igds_style attribute. Range: String Default: No default
igds_symbology		A single integer encoding the element’s style, weight, and color according to this formula: symbology = style + 8weight + 256 color This attribute will override the individual settings for style, style name, weight, and type if it is specified. Range: 0..65536 Default: None
igds_transparency	Version 8	Represents the transparency or opacity of an element, where a value of 0.0 is fully opaque, and a value of 1.0 is fully transparent. Used for both reading and writing elements. Range: 0.0..1.0 Default: 0.0
igds_type		The FME name for the type of element this feature represents. Range: See the table in the Overview subsection. Default: No default
igds_weight		The element’s line weight. This attribute will be overridden by the igds_symbology value. Range: 0..31 Default: 0
igds_weight_set_bylevel	Reader only Version 8	Set to Yes if the element’s weight is set by level; otherwise it is set to No. If it is set to Yes, the writer sets the element’s property to pick the weight from the level it is on. Range: Yes/No Default: No default
igds_xlow		The element's minimum X value in ground units. The value of this attribute is ignored when writing. Range: Any Number
igds_xhigh		The element's maximum X value in ground units. The value of this attribute is ignored when writing. Range: Any Number
igds_ylow		The element's minimum Y value in ground units. The value of this attribute is ignored when writing. Range: Any Number
igds_yhigh		The element's maximum Y value in ground units. The value of this attribute is ignored when writing. Range: Any Number
igds_zlow		The element's minimum Z (elevation) value in ground units. The value of this attribute is ignored when writing 3D files to V7, and is ignored when writing to V8. Range: Any Number Default: No default
igds_zlow_uor	The value of this attribute is ignored when writing 3D files to V7, and is ignored when writing to V8.	The element's minimum Z (elevation) value in UORs. The value of this attribute takes precedence over igds_zlow when the feature is written. Range: Any Number Default: No default
igds_zhigh		The element's maximum Z (elevation) value in ground units. The value of this attribute is ignored when writing 3D files to V7, and is ignored when writing to V8. Range: Any Number Default: No default
igds_zhigh_uor	The value of this attribute is ignored when writing 3D files to V7, and is ignored when writing to V8.	The element's maximum Z (elevation) value in UORs. The value of this attribute takes precedence over igds_zhigh when the feature is written. Range: Any Number Default: No default
igds_custom_linestyle	Version 7	If an element has a custom line style, then this attribute will contain the name of the custom line style. It does not appear as part of the attributes of the element in case it does not have any custom line styles defined for it. Range: String Default: No default
igds_custom_linestyle_rbit	Version 7	This is used to write the custom line styles. This value sets the rbit of the user linkage. Range: 0 or 1 Default: 0
igds_custom_linestyle_mbit	Version 7	This is used to write the custom line styles. This value sets the mbit of the user linkage. Range: 0 or 1 Default: 0
igds_custom_linestyle_ibit	Version 7	This is used to write the custom line styles. This value sets the ibit of the user linkage. Range: 0 or 1 Default: 0
igds_custom_linestyle_class	Version 7	This is used to write the custom line styles. This value sets the class of the user linkage. Range: 0 or 1 Default: 0
igds_custom_linestyle_flags	Version 8	If an element has a custom line style, this attribute will contain the flags portion of the header for the custom line style linkage. It always appears when reading, but is optional when writing. Range: 0..255 Default: 16 (basic user linkage)
igds_custom_linestyle_scale	Version 8	If an element has a custom line style, this attribute will contain the scale factor which is applied to the line style, if it exists. Range: Any positive number Default: 1.0
igds_custom_linestyle_start_width	Version 8	If an element has a custom line style, this attribute will contain the starting width of the line style in master units, if it exists. Range: Any positive number Default: 0.0
igds_custom_linestyle_end_width	Version 8	If an element has a custom line style, this attribute will contain the ending width of the line style in master units, if it exists. Range: Any positive number Default: 0.0
igds_custom_linestyle_distance_shift	Version 8	If an element has a custom line style, this attribute will contain the shift of a line style from the start of an element as a distance in master units, if such a shift exists. This is mutually exclusive with igds_custom_linestyle_fraction_shift and igds_custom_linestyle_center_shift. Range: Any positive number Default: 0.0
igds_custom_linestyle_fraction_shift	Version 8	If an element has a custom line style, this attribute will contain the shift of a line style from the start of an element as a fraction of the element, if such a shift exists. This is mutually exclusive with igds_custom_linestyle_distance_shift and igds_custom_linestyle_center_shift. Range: Any positive number Default: 0.0
igds_custom_linestyle_center_shift	Version 8	If an element has a custom line style, this attribute will contain YES if the line style will be centered for an element, if such a shift exists. This is mutually exclusive with igds_custom_linestyle_distance_shift and igds_custom_linestyle_fraction_shift. Range: YES or NO Default: No default
igds_custom_linestyle_rotation	Version 8	If an element has a custom line style, this attribute will contain the counter-clockwise rotation angle of the line style for the element, if such a rotation exists. Range: Any positive number Default: 0.0
igds_element_byteoffset		This is used to tell the position of the element. Range: Any Number Default: No default
igds_model_name	Version 8	The name of the model to which the feature belongs. Range: String Default: No default
igds_model_id	Version 8	The ID of the model to which the feature belongs. When writing, this indicates the model (taken from the seed file) to which a feature will be written. Range: Any positive integer Default: No default
igds_element_new		The NEW property of the element. Range: YES or NO Default: No default
igds_element_priority	Version 8	The property of an element which is used to determine draw order in design files. Primarily for 2D elements, but may be useful for 3D elements with matching Z values. Range: -500 .. 500 Default: 0
igds_element_modified		The MODIFIED property of the element. Range: YES or NO Default: No default
igds_date_last_modified	Reader only Version 8	Stores the date the element of last modified in the format YYYYMMDD hh:mm:ssAM/PM. Default: No default
igds_element_locked		The LOCKED property of the element. Range: YES or NO Default: No default
igds_element_id	Version 8	The unique ID of each element in a DGN file. Range: Any positive integer Default: No default
mslink_x		Value of mslink key of the corresponding linkage, where x is the index into the set of linkages which have an mslink key. Only some linkages, such as database and dmrs linkages, have an mslink key. Thus it may not exist at all for linkage lists which only have other types. When mslink keys do exist, x is an index value for the sequential ordered set of any such linkages, where the index starts at 0. Example Linkage list: igds_linkage{0}.entity_number 4 igds_linkage{0}.key 1001 igds_linkage{0}.type dbase igds_linkage{1}.flags 16 igds_linkage{1}.string TREE igds_linkage{1}.string_id 1 igds_linkage{0}.type dbase igds_linkage{0}.entity_number 5 igds_linkage{0}.key 1002 igds_linkage{0}.type dbase Related attributes: entity_num_0 4 entity_num_1 5 mslink_0 1001 mslink_1 1002 link_type_0 dbase link_type_1 dbase Default: No default
entity_num_x		Value of entity_number of the corresponding linkage where x is the index into the set of linkages which have an mslink key. Entity numbers parallel the existence of mslink keys.Only some linkages, such as database and dmrs linkages, have an mslink key. Thus it may not exist at all for linkage lists which only have other types. When mslink keys do exist, x is an index value for the sequential ordered set of any such linkages, where the index starts at 0. See mslink_x for an example. Default: No default
link_type_x		Value of link type of the corresponding linkage, where x is the index into the set of linkages which have an mslink key. Though every linkage has a type, link type parallels the existence of mslink keys. Only some linkages, such as database and dmrs linkages, have an mslink key. Thus it may not exist at all for linkage lists which only have other types. When mslink keys do exist, x is an index value for the sequential ordered set of any such linkages, where the index starts at 0. See mslink_x for an example. Default: No default
igds_element_association_id		The tags store this ID as the element ID it is attached to.
igds_z_value		This attribute is for the writer only and should be used only when 3D is intended to be forced. (IGDS only) Default: 0
igds_chain_number		FME adds the attribute igds_chain_number to each element of a chain split. Default: No default
igds_deleted	Version 7	When reading, this attribute is set to Yes only when the element read was a deleted element. Default: No default
igds_element_visibility	Version 8	When reading, this attribute has the value Yes if the level the element is on has its display property set to on; otherwise, the value is No. Default: No default
igds_level_freeze	Version 8	When reading, this attribute has the value Yes if the level the element is on has its freeze property set to on. Default: No default
igds_level_lock	Version 8	When reading, this attribute has the value Yes if the level the element is on has its lock property set to on. Default: No default
igds_element_view_independent		When reading, this attribute has the value Yes if the element is view-independent, and the element type supports being view-independent. Otherwise, the value is No. When writing, those elements which support being view-independent will be set to be view-independent, unless this attribute exists and is set to a value of No. Other values for this attribute, such as Yes, will do nothing for elements which do not support being view-independent. Default: Yes
igds_is_graphic_cell_relative		This attribute is for graphic cells only. It is ignored for point cells and shared cells. If this attribute is set to Yes, then the graphic cell is written as relative graphic cell. This means that the cell member with the lowest level number will be put on the current (feature's) level. All the subsequent ones are offset accordingly. For example, if a cell had members on level 4, 6 and 7 respectively and we are writing this cell feature on level 2, then the member with level 4 gets written on level 2. The members with level 6 and 7 are written on level 4 and 5, respectively. This also applies to members of nested cells. Note that all the offset levels should be provided in the seed file, otherwise the cell would be skipped. When writing to Version 8 DGN files only, if the igds_level is not supplied, the level name will be used to look up the level number in the seed file. Default:No
igds_xfm_data prefix	Version 8	A binary encoded string value for the bytes prefixing the core data of an XFM item for an element. This is application-specific and may by used to construct XFM data for an element when writing. However, it may be calculated when writing if not supplied. Range: A valid context-specific variable length binary encoded string Default: No default
igds_xfm_name	Version 8	This attribute is used when reading an XFM feature element or XFM reference element. It indicates the name of the XFM feature. This attribute is used when writing elements which have XFM information. Then this attribute indicates the name of that element. Default: No default
igds_xfm_parent_uuid	Version 8, XFM Select Series 1 version	A Universally Unique Identifier (UUID) for this XFM feature element, acting as an identifier for a reference to hierarchical parent XFM data. When writing, this attribute is required create an XFM UUID specific data. Range: Any UUID value in string format Default: No default
igds_xfm_ref_elem_id	Version 8, XFM Select Series 3 version	The identifier of an element for referencing XFM data. Range: Any positive integer Default: No default
igds_xfm_root_uuid	Version 8, XFM Select Series 1 version	A Universally Unique Identifier (UUID) for this XFM feature element, acting as an identifier for a reference to hierarchical root XFM data. When writing, this attribute is required create an XFM UUID specific data. Range: Any UUID value in string format Default: No default
igds_xfm_url	Version 8, XFM Select Series 3 version	The UNICODE (UTF-16) encoded string for an XFM feature URL fragment. This is typically found on an XFM reference feature. However, it may appear on other features that contain XFM data. Range: Any valid URL String. Default: No default
igds_xfm_uuid	Version 8	A Universally Unique Identifier (UUID) for this XFM feature element, acting as an identifier for referencing XFM data. When writing, this attribute is required create an XFM UUID specific data. Range: Any UUID value in string format Default: No default
igds_xfm_xml	Version 8, XFM Select Series 3 version	The UNICODE (UTF-16) encoded string for an XFM feature XML fragment. This is typically found on an XFM reference feature. However, it may appear on other features to indicate that they contain XFM data. See igds_xfm_name above for feature naming in this case. Range: Any valid XML String, though for writing, it should match an XFM project schema. Default: No default
igds_xfmstore_url	Version 8, XFM Select Series 1 version	The UNICODE (UTF-16) encoded string for an XFM feature URL fragment. This is typically found on an XFM reference feature. However, it may appear on other features to indicate that they contain XFM data. Range: Any valid URL String. Default: No default
igds_xfmstore_xml	Version 8, XFM Select Series 1 version	The UNICODE (UTF-16) encoded string for an XFM feature XML fragment. This is typically found on an XFM reference feature. However, it may appear on other features to indicate that they contain XFM data. In this case, the DGN V8 Writer automatically creates XFM data including any related XFM reference element. See igds_xfm_name above for feature naming in this case. Range: Any valid XML String, though for writing, it should match an XFM project schema. Default: No default

The following topics describe parameters specific to each of the supported element types: