General types of lines

1. AutoCAD tip – line, spline or polyline?
CREATING LINEWORK
Creating linework is the primary method used to produce a drawing in AutoCAD. As such it is
vital to ensure that your workflow produces clean and efficient linework - both for the initial
creation AND for all future amendments to it. It is worth bearing in mind that the future
amendments might be undertaken by another member of your team. No-one likes to work on a
poorly created drawing. It's pretty annoying...but more importantly it is inefficient. Poor
linework costs money.
LINE, SPLINE OR POLYLINE?
Three of the most common linework drawing tools available in AutoCAD are the LINE, SPLINE
and POLYLINE. They each have their own unique characteristics and produce different results.
In our experience one of them is vastly superior for producing clean and efficient drawing
linework.
Some time ago we conducted a SURVEY asking AutoCAD users which of these three linework
types they thought was the most efficient - see the RESULTS here.
To help you decide which linework type is best suited to your needs we will examine the
individual characteristics of all three - the LINE, SPLINE and POLYLINE. We will also give
our personal experience of using all three linework types in a construction environment.
Ultimately the choice is yours - we are giving you the necessary information to help you make
that choice.
1. LINE
With the line command you pick a start and end point and AutoCAD will draw a
simple line connecting the 2 points. You can continue to pick points and AutoCAD will draw a
straight line between the picked point and the previous point. Each line is an individual
segment and can be modified independent of the other lines.

2. SHORTCUTS
L | starts the command
ENTER | finishes the command
C | closes the shape
2. SPLINE
With the spline command you pick a series of points and AutoCAD will draw a
smooth curve that passes through or near a given set of points. You can control how closely the
curve fits to the points by changing the value for the fit tolerance with SPLINEDIT.
SHORTCUTS
SPL | starts the command
ENTER | finishes the command
C | closes the shape
3. POLYLINE
With the polyline command you pick a series of points and AutoCAD will draw a
joined line connecting the points. You can also use the extra features of multi-function grip to
convert to arc and add/remove vertex.
SHORTCUTS
PL | starts the command
ENTER | finishes the command

3. C | closes the shape
USEFULNESS RATING
LINE: 4/10
The line command creates very basic lines with no frills. To use the lines as a hatch boundary
you need to first join all the lines. To use the offset command efficiently you need to first join all
the lines. If you want arcs you need to create them as a separate command because there are
no additional editing functions.
SPLINE: 2/10
The spline command can create nice organic lines which may have some use in the very early
stages of Sketch or Concept Design. I think they are too inefficient and inaccurate for
construction documentation. They also create issues with huge numbers of vertices when you
offset them.
POLYLINE: 9/10
The polyline is clearly superior to the line and spline. It produces a joined line which is then
easier to use for other functions like hatch boundaries and offsetting. It has the extra editing
functionality of the multi-function grip. The polyline can provide all that the line and spline can
- but without the associated inefficiencies.