Entities (File Format) Changed in Version 2021.0

An entity consists of a header, determining the entity's type and containing some entity-specific data, and a sequence of data blocks. Each data block itself consists of a header and a variable data section.

The following entities may exist in drawing, library and collection files:

Entity "Object"

This entity represents the smallest display element of drawings. An object may be a line, a circle, a text etc. It consists of a header, geometrical data and some object-specific data. For basic structure of the entity type "Object" see MKI_ENTITY_OBJECT.

Standard Objects

Standard objects are "simple" objects that can be assembled of lines, circle parts and ellipse parts.

Extended Objects

Extended objects are more complex than standard objects. Such object cannot directly be handled by trimming and other modifications. Instead, they will have to be resolved in polylines before. This requires additional processing time and leads to reduced precision.

Dimension Objects

Dimension objects are usually used to add dimensions to a drawing. In addition, they can be used to create simple arrows. Dimensions are very complex and should be handled carefully.

The following image shows the different elements of a distance dimension and their names. These names are also equally valid for other dimension forms:

Dimensions are always referring to a coordinate system. This coordinate system contains all required information about the current entities, the scale and the desired number display modes.

The examples shown in this section are mainly not according to DIN rules. Instead, they shall display all possible forms of dimension available in compact form.

Text Objects

Text objects are used for the lettering of the drawing and are basically implemented as a multi-instance of characters.

Construction Aid Objects

Construction Aid objects are used to create an auxiliary Construction Aid for easy and fast construction. They are not relevant for printer or plotter output (except if explicitly activated by the user) and will only be displayed on the screen. Construction Aid objects can usually be ignored during file conversion.

Supplementary Objects

Supplementary objects usually exist only in special location such as display or data lists of extended entities.

Entity "Instance"

This entity represents an instance (internal or external reference) of a block. It is used to reference and display a block definition.  For basic structure of the entity type "Instance" see MKI_ENTITY_INSTANCE.

Entity "Block"

This entity represents either an internal (inside a drawing file) or an external (inside a library file) block definition. Both definitions are handled similar, they both are a named collection of multiple entities, being referenced by instances (see above). For basic structure of the entity type "Block" see MKI_ENTITY_BLOCK.

Entity "Clipping"

A "clipping" is a combination of a surface-formed outline and a list of objects / entities that are clipping towards this surface. For basic structure of the entity type "Clipping" see MKI_ENTITY_CLIP.

Entity "Mapping"

A "mapping" is a projection of a drawing section into another location of the same drawing. For basic structure of the entity type "Mapping" see MKI_ENTITY_MAPPING.

Entity "Drawing Reference"

A "drawing reference" is a reference to a drawing file. It is used to display a complete drawing within another drawing. For basic structure of the entity type "Drawing Reference" see MKI_ENTITY_REF.

Entity "Group" Changed in Version 2017.0

A group is an assembly of multiple entities that are usually handled as one. For basic structure of the entity type "Group" see MKI_ENTITY_GROUP.

In older versions of the file format prior to version 2017.0, groups were a special form of the entity "Block". The BlockName of such group blocks started with "#G" and could only exist as internal blocks.

Entity "Position Number" Changed in Version 2017.0

A "position number" is a special form of the entity "Group". It contains the referenced entities, a reference text displaying the position number, and an attribute with the name "#AutoPosNum".

In older versions of the file format prior to version 2017.0, position numbers were a special form of the entity "Block". The BlockName of such group blocks started with "#P" and could only exist as internal blocks.

Entity "Hatching" New in Version 2018.2

A "hatching" is a set of curves dynamically created based on a surface and hatching type definition. For basic structure of the entity type "Hatching" see MKI_ENTITY_HATCH.

Entity "Extended"

This entity represents an extended entity, i.e. an entity that was created by an plug-in. Such an entity can only be displayed and modified if an plug-in is present that knows how to handle such an entity. For basic structure of the entity type "Extended" see MKI_ENTITY_EXT.

Entity "End of List"

This entity marks the end of an entity sequence. Such an entity terminates each section containing entities and each block definition. For basic structure of the entity type "End of List" see MKI_ENTITY_BASE.