Converts 2D and 3D polylines between modern lightweight and classic polylines (heavyweight) definitions.

BricsCAD Lite; BricsCAD Pro; BricsCAD Mechanical; BricsCAD BIM


The main benefit of this command is to reduce the drawing file size by using lightweight polyline definitions.

This command does not convert the following types of polylines:

  • Curve-fit.
  • Splined polylines.
  • Polylines with extended object data stored on their vertices.
Note: BricsCAD ignores ineligible entities.

You may not need to use this command in the following situations:

  • When editing commands apply to both classic and lightweight polylines.
  • You can also use the PLINETYPE system variable to specify if classic polylines are automatically converted to lightweight polylines when an older drawing is opened. This system variable determines which style of polyline is created in new drawings.
Note: You can enter this command transparently during commands (‘convertpoly).



Converts lightweight and 3D polylines to heavyweight ones.

This might be necessary to make drawings compatible with certain software.


Converts heavyweight and 3D polylines to lightweight ones.

After selecting, you are prompted:

Split 3d polyline into planar polylines if it is not planar?[Yes/No] <Yes>:

  • Yes: 3D polylines are converted.
  • No: 3D polylines are not converted.
Converts lightweight and heavyweight polylines to 3D polylines.