CAD:Vector Based

The CAD file is a vector based file. That is to say that the items in the file are maintained as entity types (e.g. line, circle, etc) with their coordinates and properties stored in the file as opposed to a pixel map. To view the drawing all entities on visible layers are rendered to a pixel map and rasterized to the monitor.

This approach allows for easy scaling and transformation.

Description

Coordinates are being expressed in drawing units.Drawing units are not expressing particular units(meters,inches etc). In this part user have to make some assumptions in order to define that the coordinates of the drawing mean particular units(meters,inches etc). For example: For a mechanichal drawing we can make the assumption for example: where one drawing unit defines one millimeter(1 D.U=1mm) For a architectural/technical drawing we can make the assumption for example: where one drawing unit defines one meter(1 D.U=1m) This can be very helpfull in designing,dimensioning,retrieving informations from the drawing(distances,area calculations)