DXF:
Drawing Interchange Format (or) Drawing Exchange Format.
History:
In 1982 by AutoDesk.
Functional diagram:
Tagged data representation of autocad file.
Vector graphic file format.
Distinguished from raster images.
Drawing entity is defined by group code and its value.
Group code:
Numerical order and organizes them by object type.
Representation:
In group code ranging from 1 to 1071.
Structure:Several sections.
Each section is composed of records turned in to group code.
Section
|
Basic description
|
|---|---|
Header
|
General information about drawing which autocad version have to uses or units to measure angles
|
Classes
|
Information for application defined classes instances appears in blocks, entities, objects of database
|
Tables
|
Different symbol entries line table dashes, dots, text in dxf file
|
| Blocks |
Graphical objects and drawing entities each block reference in drawing
|
| Entities |
Actual object data and graphical entities include raw data for example circle entry is defined by thickness
|
Objects
|
Non graphical parts like autocad dictionaries
|
Why DXF different to other CAD file formats:
Open source.
Source code is freely available and developers can use.
Supported by all CAD programs in market.
DXF used for:
Exchange of data.
Act as conduit between different vector graphic formats.
Example:
File created in AutoCAD saved as DXF can be opened in Adobe illustrator.
When we go for DFX:
File sharing between two CAD programs.
Who uses DXF files:
Architectural designer.
Store owner.
Archaeologist.
Advantages:
Most compatible vector file type.
Exchange data between different CAD programs.
Easy to parse.
Specification is publicly available.
Disadvantages:
Cannot support specific CAD elements.
DXF files become large in size.
Cannot deal with line widths.