AutoCAD Color Index (ACI)¶
color attribute represents an ACI
(AutoCAD Color Index).
AutoCAD and many other CAD application provides a default color table,
but pen table would be the more correct term.
Each ACI entry defines the color value, the line weight and some other
attributes to use for the pen. This pen table can be edited by the user or
loaded from an CTB or STB file.
Ezdxf provides functions to create (
new()) or modify
ezdxf.acadctb.load()) plot styles files.
DXF R12 and prior do not preserve the layout of a drawing very well, because
of the lack of a standard color table and missing DXF structures to define
these color tables in the DXF file.
If a CAD user redefines an ACI color entry in a CAD application and does not
provide this CTB or STB file, you can not know what color
or lineweight was used intentionally.
This got better in later DXF versions by supporting additional DXF
true_color which can define these
attributes by distinct values.