[Search tip detail and code files using keywords, tip number, author name, etc ]
    For tip to function correctly, you must ensure that the downloaded file name matches the file name
    displayed in the Rename File To field. Please rename downloaded files when necessary.
Entity to Directional Arrows
Tip# 4191 By Raymond Rizkallah On 22-Sep-2013
Rated By 0 users Downloaded : 1337
Categories : 2D Operations, 2D Editing
Software type : AutoCAD 2014
Rename File To : ARROW-BREAK.LSP
Convert a polyline, line, or arc into a series of arrows.

This AutoCAD routine from Raymond Rizkallah converts a polyline, line, or arc into a series of arrows. This could be very useful for showing direction.

Load the LISP file, then run the command ARB. Select a polyline, line, or arc, noting that the arrow direction is determined by the pick location. Specify the arrowhead length in drawing units and press Enter. The selected entity will be replaced with a series of arrowheads and arrowhead tails, forming a chain of directional indicators. If you are not happy with the arrowhead size, a single "U" will undo the entire command, and you can easily repeat the process. See the image below for a sample of before and after.


Average Rating:

User comments
Comment by Rizkallah,Raymond
Posted on 2013-09-24 01:33:22
You can enhance the routine by replacing the VALID OBJECTS line 17 : (setq ValidEntList '("LWPOLYLINE" "LINE" "ARC")) by : (setq ValidEntList '("LWPOLYLINE" "LINE" "ARC" "ELLIPSE" "SPLINE" "CIRCLE"))
Comment by Cooper,Kent
Posted on 2013-10-01 09:23:40
If you use it on a CLOSED Polyline, and if you add Circle/Ellipse/Spline entity types as suggested and use it on a Circle or a closed Ellipse or Spline, there will be the irregularity that there will be NO GAP between the arrowhead at the start/end location (zero-degree direction in the case of a Circle) and the tail of the next arrow. That could be accounted for with some editing of the code. Using a LINETYPE defined to look something like this has many advantages. It won't have that irregularity at the start/end location. The overall "path" remains a SINGLE entity. That means that you can select it (to Move, Copy, Erase, etc.) in ONE pick, instead of needing to catch all those independent arrowheads and tails. That also means that if you adjust it in any way (change the radius of a Circle, Extend or Trim the end(s) of something open-ended, Pedit a Polyline, any kind of Stretch, etc.), the whole thing adjusts accordingly. The only real DISadvantage of using a linetype is in arrowhead positioning: it typically won't have an arrowhead AT the one end, but there will be some piece of path entity past that, and often the tail part of the arrow at the other end won't be the same length as the others. But if you can live with that shortcoming, the benefits are significant. Such a linetype could be defined using a Shape for the arrowhead, or a text character. Some symbol fonts such as in the Wingdings family have characters that could be used to look like this. I have a definition that's very like this except for the shape of the arrowhead -- it uses a greater-than character > [I don't this website is going to honor line breaks, so you'll need to get those back in the right places]: *ARROWS,--------> --------> --------> -------- A,4.0,[">",ROMANS,S=1.0,R=0.0,X=-0.95237,Y=-.4285657],-1.0