Reader Directives

The IGDS reader processes the <ReaderKeyword>_DATASET directive in the mapping file. The value for this directive is the file name of the IGDS file to be read. By default, the <ReaderKeyword> for the IGDS reader is IGDS, so a typical mapping file fragment specifying an input IGDS file looks like:

IGDS_DATASET /usr/data/dgn/92b034.dgn

The IGDS reader also processes the <ReaderKeyword>_UNITS directive in the mapping file. This directive controls the conversion between UORs in the Design file and FME coordinates. There are three possibilities, outlined in the table below. If no UNITS directive is specified, then IGDS_SUB_UNITS is assumed for V7, and IGDS_MASTER_UNITS is assumed for V8.

Note that for each of these conversions the coordinates of an FME Feature will be represent the coordinates as scaled by the <ReaderKeyword>_UNITS selection. Those coordinates are all relative to working coordinates.

See ASSUME_MATCHING_UNITS for further details on DGN V8 reading.

IGDS_UNITS Value Description

IGDS_MASTER_UNITS

The UORs read from the Design file are converted into master units, according to the conversion factor read from the Design file header, before being stored in an FME feature.

IGDS_SUB_UNITS

The UORs read from the Design file are converted into subunits, according to the conversion factor read from the Design file header, before being stored in an FME feature.

IGDS_UORS

The UORs read from the Design file are read as raw UOR coordinates.

The IGDS reader processes several other directives in the mapping file, as shown below. These enable the FME to override the Global Origin and Scaling information. The first four directives are normally used only when reading Design files that have bad header information. If the FME detects a difference between these settings and those read from the Design file, a warning is output to the log file and these settings prevail.

The IGDS reader can also be configured to output all the elements composing cells, or symbols. This is useful if the graphical representation of the Design file is to be preserved. This is true when, for example, a Design file is translated to a GIF image.

UOR_SCALE

Required/Optional: Optional

The number of ground units per UOR

Values

A double precision floating point number

Workbench Parameter

UOR to FME Feature Coordinate Units scale factor

UOR_GLOBAL_ORIGIN_X

Required/Optional: Optional

The global origin of x measured in UORs, from the lower left corner of the design plane/cube.

Values

An unsigned 32 bit integer value

Workbench Parameter

UOR X Global Origin

UOR_GLOBAL_ORIGIN_Y

Required/Optional: Optional

The global origin of y measured in UORs, from the lower left corner of the design plane/cube.

Values

An unsigned 32 bit integer value

Workbench Parameter

UOR Y Global Origin

UOR_GLOBAL_ORIGIN_Z

Required/Optional: Optional

The global origin of z measured in UORs, from the lower left corner of the design plane/cube.

Workbench Parameter

UOR Z Global Origin

SUBS_PER_MASTER

Required/Optional: Optional

The number of sub units per master unit. This is only used if UOR_SCALE is not present.

Values

An unsigned 32 bit integer value

Workbench Parameter

SUBS PER MASTER UNIT

UORS_PER_SUB

Required/Optional: Optional

The number of UORs per sub unit. This is only used if UOR_SCALE is not present.

Workbench Parameter

UORS PER SUB UNIT

ASSUME_MATCHING_UNITS

Values: YES | NO

Default Value: NO

Required/Optional: Optional

Set to allow the assumption that working units are equal to master units. This affects all calculations involving conversion from UOR coordinates to coordinates any known unit, such as when the UNITS directive is set to Sub units, or Master units. If set to NO, then the working unit of the design file will be additionally used in the calculation of coordinates.

Workbench Parameter

Assume master units are equal to working units (V8 only)

EXPAND_CELLS

Required/Optional: Optional

Controls whether or not all components of a cell will be output by the reader.

If the value is YES, then they are and the cell header itself is not output. If the cell header had any linkage attributes, these will be propagated to the component elements.

If it is NO, then only the cell header is output.

Values: YES | NO

Default Value: NO

Workbench Parameter

Expand Named Cells

EXPAND_UNNAMED_CELLS

Required/Optional: Optional

This directive should not be confused with EXPAND_CELL in terms of its usage. It is better understood in relation to igds_solid. When it is set to YES, then no donuts are formed even if they existed and the cell members retain their colors. If the header had any linkage attributes, these will be propagated to the component elements. When it is set to NO, then donuts will be formed if they existed, and the pieces may lose their original colors.

Values: YES | NO

Default Value: NO

Workbench Parameter

Expand Unnamed Cells

PRESERVE_CELL_INSERTS

When EXPAND_CELLS is set to YES, this directive controls whether or not the insert points of the cells are also output.

Values

YES: The cell insert points are output as igds_cell features in addition to the cell components

NO (default): Only the cell components are output.

Required/Optional

Optional

Workbench Parameter

Preserve Named Cell Inserts

PRESERVE_UNNAMEDCELL_INSERTS

Required/Optional: Optional

If the value is YES, then the cell insert points are output in addition to the cell components.

If it is NO, then only the cell components are output.

Values: YES | NO

Default Value: NO

Workbench Parameter

Preserve Unnamed Cell Insert Points

TAGS_AS_TEXT

Controls whether or not visible tag data elements are output as separate text elements, in addition to having their data attached to the primary graphic element they go with.

Required/Optional

Optional

Values

YES | NO (visible tag data elements are not output as text elements)

Workbench Parameter

Output Tags as Text

PRESERVE_CURVES

This directive controls whether or not curve elements will be stroked into lines by adding vertices.

If set to YES, then the control points of the curve are connected into a line. Otherwise, the control points used to interpolate a linear representation of the curve.

Required/Optional

Optional

Values

YES: Preserves the original control points and the end slopes. This is primarily used for DGN-to-DGN translations.

NO: Strokes (vectorizes) the curve (this is, it preserves the shape of the curve).

Workbench Parameter

Preserve Curves

ELEVATION_SHIFT_FACTOR

If an elevation shift is desired to build "fake" 3D topology, this is the scaling factor used to generate the shift.

Specifically, the Z value is divided by this factor and the result is added to the X value.

Required/Optional

Optional

Workbench Parameter

Elevation Shift Factor

CURVE_VERTICES

This directive is used only when PRESERVE_CURVES is set to NO.

It controls the number of points per segment when the curve is interpolated into a line.

Required/Optional

Optional

Default Value

5

Workbench Parameter

Number of interpolated curve vertices

TRIM_DOWN_TAGS

Removes the tag attributes when set to YES.

Required/Optional

Optional

Values

YES | NO (default)

Workbench Parameter

Strip Off Tag Information

SPLIT_MULTITEXT

When set to YES, the reader splits the multi-text into text nodes and outputs the member text elements as individual text elements. If the multi-text had any linkage attributes, these will be propagated to the component elements.

When set to NO, the text elements are not split.

Required/Optional

Optional

Values

YES (default) | NO

Workbench Parameter

Split multi text

READ_BYTE_OFFSET

Required/Optional: Optional

Version: supported for version 7 only

If set to YES, adds the igds_element_byteoffset attribute (which contains the position of the element in the .dgn file) to the feature. Note, however, that turning this option on might significantly slow down reading on some platforms like UNIX.

Values: YES | NO

Default Value: NO

EXPLODE_DIMENSION_ELEM

Required/Optional: Optional

If set to YES, explodes the dimension element into its pieces. If the dimension had any linkage attributes, these will be propagated to the component elements. If set to NO, then imports the dimension element as an aggregate. When importing as an aggregate, the text members are not output as features but are stored as list attributes of the dimension, and the arc members are stroked.

Values: YES | NO

Default Value: YES

READ_XREF_FILES

If set to YES, reads all the supported elements in the external reference files attached to the source dataset. If the reference file has nested references, they may also be imported.

Note: The reading of reference file elements as features with an igds_type of igds_xref is affected by the READ_XREFS_AS_ELEMENTS directive and not this directive.

Required/Optional

Optional

Values

YES | NO (default)

Workbench Parameter

Read Elements From Reference Files

READ_XREF_UPTO_FIRST_LVL (deprecated)

This has been superseded by the Max Depth of Reference Files to Read directive.

If set to YES, reads all the supported elements in the external reference files attached to the source data set up to the first level of nesting only.

This directive is valid only if READ_XREF_FILES is set to YES.

Required/Optional

Optional

Values

YES | NO (default)

Workbench Parameter

Read Reference up to First Level

READ_XREF_NEST_DEPTH

This supersedes the Read_Reference up to First Level directive.

This directive is valid only if READ_XREF_FILES is set to YES.

Required/Optional

Optional

Values

YES | NO (default)

Workbench Parameter

Max Depth of Reference Files to Read

USE_XREF_PARENT_MODEL

This directive is applicable to version 8 only, since models are supported in version 8 but not in version 7.

If set to YES, uses the model of the parent file of the xref file.

This directive is valid only if READ_XREF_FILES is set to YES.

Required/Optional

Optional

Values

YES (default) | NO

Workbench Parameter

Use Reference's Parent Model (V8 only)

READ_XREFS_AS_ELEMENTS

This directive is applicable to version 8 only.

Note: The reading of all supported elements in external reference files is affected by the Read Elements From Reference Files parameter (not this parameter).

Required/Optional

Optional

Values

YES (default) | NO

Workbench Parameter

Keep Elements That Represent Reference Files (V8 only)

EXPLODE_MULTI_LINE

Required/Optional: Optional

If set to yes, then multi-lines are exploded into its pieces. If the multi-line had any linkage attributes, these will be propagated to the component elements.

Values: YES | NO

Default Value: NO

READ_DELETED_ELEMENTS (applies to IGDS V7 file reading only)

Required/Optional: Optional

This directive is used to read deleted elements from V7 design files.

Note: This directive will not be made available in Workbench Format Parameters. To use this directive, it has to be set to TRUE in the mapping file.

Values: TRUE | FALSE

Default Value: FALSE

APPLY_WORLD_FILE

Use this directive when you have an Esri World file (*.wld) that you want FME to use when determining the coordinates for features in your dataset.

When this directive has a value of YES, FME will search the folder of the dataset for a file with the same name as your dataset but with a .wld extension. If it cannot find a file with that name, it will then look for the file “esri_cad.wld” within the dataset folder.

If either of those files exist, FME will use the information in the files to translate the coordinates of the features in the dataset to their new geospatial coordinates.

If the files cannot be found, then the translation will continue, using the coordinate information found in the dataset, without performing any additional transformation.

Required/Optional

Optional

Values

  • YES (Workbench default)
  • NO (mapping file default)

Workbench Parameter

Apply World File (.wld)