IGES Reader

Supported Entities

Entities supported by the IGES reader.
  • Circular arc (100)
  • Composite curve (102)
  • Conic arc (104)
  • Copious data (106)
  • Plane (108)
  • Line (110)
  • Parametric spline curve (112)
  • Parametric spline surface (114)
  • Point (116)
  • Ruled surface (118, form 1 only)
  • Surface of revolution (120)
  • Tabulated cylinder (122)
  • Direction (123)
  • Transformation matrix (124)
  • Flash (125)
  • Rational B-spline curve (126)
  • Rational B-spline surface (128)
  • Offset surface (140)
  • Boundary (141)
  • Curve on a parametric surface (142)
  • Bounded surface (143)
  • Trimmed (parametric) surface (144)
  • Manifold solid B-rep object (186)
  • Plane surface (190)
  • Right circular cylindrical surface (192)
  • Right circular conical surface (194)
  • Spherical surface (196)
  • Toroidal surface (198)
  • Angular dimension (202)
  • Diameter dimension (206)
  • General label (210)
  • General note (212)
  • Leader (214)
  • Linear dimension (216)
  • Radius dimension (222)
  • General symbol (228)
  • Sectioned area (230)
  • Line font definition (304)
  • Subfigure definition (308)
  • Color definition (314)
  • Form 7 group without back pointers (402)
  • Drawing (404)
  • Form 15 name (406)
  • Singular subfigure instance (408)
  • View (410)
  • Vertex (502)
  • Edge (504)
  • Loop (508)
  • Face (510)
  • Shell (514)

Import Options

The IGES reader uses the iges_reader.ini file. The first section of this file contains instructions for reading each type of IGES entity. It is recommended that you do not change this section. The second section controls the options for the translator.
@CheckFacet
Value Description
on Based on the success of the normal faceting operation, more cleanup attempts may be required. One option is to mesh it in advance to check the faceting. This may slow down the import due to the possible use of meshing operations, but should result in cleaner surfaces (default).
off Do not check the faceting and apply normal cleanup.
@CleanupTol
Value Description
double A negative value (default) indicates to use the auto cleanup tolerance. A value greater than the calculated auto cleanup tolerance indicates to use that specific tolerance. Refer to the CAD Cleanup Tolerance.
@ColorsAsMetadata
Value Description
on

Read color attributes of geometric entities as metadata.

COLOR_RGB
off Do not read color attributes (default).
@CreationType
Value Description
Parts Generate a full part-based hierarchy.
BOMOnly Generate an empty part-based hierarchy.
TreeOfComponents Generate an assemblies/components based hierarchy.
PackIntoSinglePart Consolidate hierarchy into a single part.
@DoNotMergeEdges
Value Description
on Preserve the original geometry edges, instead of merging them together during the import cleanup phase.
off Merge edges together during the import cleanup phase (default).
@GroupAsRegions
Value Description
on Create region entities corresponding to IGES groups.
off Do not create region entities. (default).
@ImportBlanked
Value Description
on Import entities that are hidden, blanked, or no show.
off Do not import entities that are hidden, blanked, or no show (default).
@ImportForVisualizationOnly
Value Description
on

Import the model for visualization purposes only.

This skips many of the import steps (cleanup, stitching, solid creation, and so on) to provide a faster import. The resulting model may not be suitable for other uses.
off Import the model in the normal fashion (default).
@ImportFreeCurves
Value Description
on Import free curves (wireframe entities) into the model (default).
off Do not import free curves.
@ImportFreePoints
Value Description
on Import free points into the model (default).
off Do not import free points.
@ImportLayers
Value Description
Layers to skip

Enables the specification of layer numbers to import, in order to skip unwanted layers.

To specify layer groupings, enter  a hyphen between the beginning and ending values of the desired group.  Groups are separated by commas.

Example:  @ImportLayers = "1,2-5,100-200"
@ImportType
Value Description
ASSEMBLY Generate an assembly tree corresponding to the one contained in the file (default).

Meaningful if @CreationType = “TreeOfComponents”.

LAYERS_ONLY Create components based on the layer (=level) structure of the file.

Meaningful if @CreationType = “TreeOfComponents”.

LAYERS_AND_GROUPS Create components corresponding to layers and groups contained in the file.

Meaningful if @CreationType = “TreeOfComponents”.

@LayerAsMetadata
Value Description
on Read layer value as metadata.

LAYER
off Do not read layer value (default).
@LegacyHierarchyAsMetadata
Value Description
on Generate metadata with the original CAD hierarchy within the part.

LEGACY_HIERARCHY
off Do not generate metadata with the original CAD hierarchy within the part (default).
@MetadataPrefix
Value Description
string The string is prefixed to all metadata names. No prefix is used by default.

See CAD Metadata Naming for more details.
@PropertyAsGroup
Value Description
NEVER_MANAGE Do not generate special metadata (default).

Meaningful if @CreationType = “TreeOfComponents”.

MANAGE_CORRECT_ONLY

Read group ID and name as metadata.

This is useful for special cases where the group ID and name have special meaning, such as to indicate a property ID and name. This applies to IGES entity type #402, form number #7.

GROUP_ID

GROUP_NAME

Meaningful if @CreationType = “TreeOfComponents”.
@ReadAsIndependent
Value Description

INDEPENDENT

PHYSICALLY_DEPENDENT

LOGICALLY_DEPENDENT

Enable the import of three types of independent entities.

Use a semicolon to separate multiple values. When more than one value is used, both independent and logically dependent entities are treated as independent. Generally, this option should only be used for a particular vendor that marks some entities as dependent when they are imported. The reader imports the entities according to the value specified in the file. The default is INDEPENDENT.
@ScaleFactor
Value Description
double Define the model scaling factor during import.

Default is 1.0.
@SkipConnectivityComputation
Value Description
on

Import the model without computing connectivity. The surfaces will not be connected.

This option speeds up import, but may not be suitable for any other purpose than visualization.
off Import the model in the normal fashion (default).
@SkipCreationOfSolid
Value Description
on Read surfaces, but do not create solid entities.
off Create solid entities (default).
@SkipEntities
Value Description
Entity types and subtypes to skip

Specific entity types, or even subtypes (that is entity types with specific form numbers) that should be skipped during import.

The list of types uses semicolons as separators.

Example: @SkipEntities = "ENTTYPE1;ENTTYPE2.FORM2"
@SplitComponents
Value Description
Body Generate body-based component (default if CreationType=Parts).
Layer Generate layer-based component.
Part Generate part-based component.
General Keep component as in CAD (default if CreationType=TreeOfComponents).
@TagsAsMetadata
Value Description
on

Read tags of supported entities as metadata (default).

TAG
off Do not read tags.
@TargetUnits
Value Description
CAD units Keep the units of the CAD files (default for GUI).
MKS [m kg N s] Convert to the corresponding units system.
MMKS [mm kg N s] Convert to the corresponding units system.
MPA [mm t N s] Convert to the corresponding units system.
CGS [cm g dyn s] Convert to the corresponding units system.
MMKNMS [mm kg kN ms] Convert to the corresponding units system.
MMGNMS [mm g N ms] Convert to the corresponding units system.
IPS Std [in pounds lbf s] Convert to the corresponding units system.
IPS Grav [in slinch lbf s] Convert to the corresponding units system.
FPS Std [ft pounds lbf s] Convert to the corresponding units system.
FPS Grav [ft slug lbf s] Convert to the corresponding units system.
Scale factor Apply the corresponding scale factor (default for no GUI to allow supporting legacy scripts).
@Transform402form16
Value Description
on

Entities referenced by an entity type #402 from #16 are transformed from 2D local space into 3D absolute space.

Early IGES files from SolidWorks require such an operation.
off (default)
@TraverseGroups
Value Description
on The reader attempts to traverse group entities (default).
off Ignore references to entities within a group.
@TrimRevolvedWithModelSpaceCurves
Value Description
on Attempt to compute the boundary definition by projecting 3D trimming curves (if such curves are available) onto the surface only for revolution surface entities (type #120).
off Use parameter space trimming loops whenever possible. Given an IGES file containing correct data, this option is faster and more robust than reading object space loops (default).
@TrimWithModelSpaceCurves
Value Description
on Attempt to compute the boundary definition by projecting 3D trimming curves (if such curves are available) onto the surface. This is useful if the parameter space trimming loops in the file contain incorrect geometry data.
off Use parameter space trimming loops whenever possible. Given an IGES file containing correct data, this option is faster and more robust than reading object space loops (default).
@TrimWithPreferredRepresentation
Value Description
on

Attempt to create the boundary definition using 2D or 3D curves, based on the preferred representation provided by entity type #142.

This option can be overridden by either @TrimRevolvedWithModelSpaceCurves = on or @TrimWithModelSpaceCurves = on.
off (default)
@UseAnsys128Format
Value Description
on Attempt to read Ansys NURBS surface format.
off (default)
@vendors
Value Description
List of vendor names

Use vendor information to search the global section of the file to determine if it is from a particular vendor. Each vendor name is separated by semicolons and all spaces in the vendor name must be replaced by an underscore.

Example: @vendors = "vendor1;vendor2;vendor3"

After a vendor has been added to the list, options for that particular vendor can be specified. If a file is recognized as coming from a particular vendor, settings for that vendor take priority over "general" settings.

Example: @<vendor>.<option> = "<value>"

Supported Metadata

Metadata generated from the IGES reader.
AUTHOR
Type Entities Description
string comps The author block as read from the 'G' section of the file. This is generated only when the block is found in the file.
AUTHORS_ORGANIZATION
Type Entities Description
string comps The author's organization block from the 'S' section of the file. This is generated only when the block is found in the file.
COLOR_RGB
Type Entities Description
string

lines

surfs

Three RGB values, ranging from 0 to 255, indicating the color of the entity in the CAD model.

Generated when @ColorsAsMetadata = on
COMMENT_BLOCK
Type Entities Description
string comps The comment block from the 'S' section of the file. This is generated only when the block is found in the file.
DRAFTING_STANDARD
Type Entities Description
integer comps The drafting standard block from the 'G' section of the file. This is generated only when the block is found in the file.
FILE_NAME
Type Entities Description
string comps The file name block from the 'G' section of the file. This is generated only when the block is found in the file.
GROUP_ID
Type Entities Description
integer comps

The IGES entity type #402, form number #7 group ID as read from the CAD model, if one exists.

Generated when @PropertyAsGroup = ManageCorrectOnly
GROUP_NAME
Type Entities Description
string comps

The IGES entity type #402, form number #7 group name as read from the CAD model, if one exists.

Generated when @PropertyAsGroup = ManageCorrectOnly
IGES_VERSION
Type Entities Description
integer comps The IGES version block from the 'G' section of the file. This is generated only when the block is found in the file.
IMPORT_DATE
Type Entities Description
string comps The import date block from the 'G' section of the file. This is generated only when the block is found in the file.
LAYER
Type Entities Description
integer
  • points
  • lines
  • surfs
  • solids
 Value of the layer of an entity.

Generated when @LayerAsMetadata=on
LEGACY_HIERARCHY
Type Entities Description
string
  • points
  • lines
  • surfs
 Hierarchy of an entity within a part.

Generated when @LegacyHierarchyAsMetadata=on
MODELUNIT
Type Entities Description
integer
  • comps
  • parts
 Model units specified in the CAD file.
  • 1 = inches
  • 2 = millimeters
  • 4 = feet
  • 5 = miles
  • 6 = meters
  • 7 = kilometers
  • 8 = mils
  • 9 = microns
  • 10 = centimeters
  • 11 = microinches
  • 12 = decimeters
  • 13 = yards

This is always generated.
MODIFICATION_DATE
Type Entities Description
string comps The modification date block from the 'G' section of the file. This is generated only when the block is found in the file.
PREPROCESSOR_VERSION
Type Entities Description
string comps The preprocessor version block from the 'G' section of the file. This is generated only when the block is found in the file.
PRODUCT_IDENTIFICATION
Type Entities Description
string comps The product identification block from the 'G' section of the file. This is generated only when the block is found in the file.
RECEIVING_PRODUCT_ID
Type Entities Description
string comps The receiving product ID block from the 'G' section of the file. This is generated only when the block is found in the file.
SYSTEM_ID
Type Entities Description
string comps The system ID block from the 'G' section of the file. This is generated only when the block is found in the file.
TAG
Type Entities Description
string

points

lines

surfs

The tag (name) of the entity as read from the CAD model, if one exists.

Generated when @TagsAsMetadata = on
UNITS
Type Entities Description
string comps The units block from the 'G' section of the file. This is generated only when the block is found in the file.