Integration with Other Applications > Windchill Workgroup Manager Documentation > CATIA V5 > User > Advanced Techniques for CATIA V5 > Managing Drawings > Drawing Reference Link
  
Drawing Reference Link
A drawing is a type of CAD document. CAD documents of type, "Drawing" are termed derived engineering drawings. A derived engineering drawing is a drawing created in your CAD application, whose views, parameters, dimensions are associatively extracted from the 3D model file(s). It can have a required reference link to a 3D model, in the case that it cannot be fully retrieved without the model information. Derived drawings are created in CATIA V5.
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Engineering drawings created in 2D systems are categorized as CAD parts or assemblies (in that they are not derived from 3D models, but rather can serve in place of 3D models). Examples of such 2D system drawings are 2D Neutral File Formats (for example, .igs, step, .dxf).
The link between a drawing CAD document and its 3D model CAD document has the following characteristics:
It is a "reference" link from the derived drawing to the 3D model.
It has the description: Drawing Model.
The system allows you to create more than one drawing link from a drawing to one or more models (for example, a drawing can be derived from two models).
The drawing link is used to collect drawings using the common collection tools (Include Drawings and Exclude Drawings).
It is a required link
For example, in CATIA V5, files with the CATDrawing extension are created as CAD document type of drawing.
The .CATDrawing files can create a drawing reference link to the following types of models:
.CATPart – CAD document type CAD part
.CATProduct – CAD document type CAD part