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Arrowheads at the end of a line

January 27 2010 | 4 comments
Categories: Cartographic Representations, Symbology

Hello,

I am trying to create arrowheads at the end of a line. Under properties, I change the type to "cartographic line symbol" and under the line properties tab I choose one of the arrowheads. However, when I change the thickness of the actual line, the end of the line seems to protrude through the front of the arrow (I have attached an example). I have tried many things such as changing the x offset of the arrow but nothing seems to work. I checked the forums and noticed this has been a problem since at least 2002. Is there a workaround to this issue? Thanks.

Mapping Center Answer:

There are a couple of cartographic representations solutions that will probably work for you. One solution is to move the arrowhead along the line and the other is to clip the line so it does not extend past the narrower part of the arrowhead.

For the first solution, you will need to reset the Position value for the marker symbol. Here is the help topic associated with the concept.

This is from the help:

  • Position: Indicates the distance from a specified location of a line that a marker will be placed. The distance is applied along the line. The default value is 0 (zero) pt.
  • Relative to: Indicates the specified location of a line from which a marker will be place. The choices are Line middle, Line beginning and Line end. The beginning and ending of a line are determined by the direction in which the line was digitized. The default value is Line middle.
  • Angle to line: Indicates whether or not markers will be oriented to the line. If unchecked, the markers will be angled to the top of the page. The default value is checked.

So you would change the Position value relative to a location on the line to move the arrowhead. The instructions are here.

ArcMap

The problem in ArcMap.

Position

Rep Rule Position

The solution using Position to reset the marker placement.

For the second solution, what you do is to clip the symbol geometry of the line so that it ends before the arrowhead narrows. Note that you will NOT be clipping the actual feature geometry. For this effect, you will need to use the Cut geometric effect. Here is the help topic associated with this topic.

Cut

Rep Rule Cut

Use of the Cut geometric effect (the value 4.375pt is created automatically when converting to representations).

Can this be automated for next release? posted by Kirsten Zecher on Feb 10 2010 9:32AM
The two solutions seem like a lot of work for something that should be built into the way a map making software draws arrowheads. Thank you.
Freedom and flexibility posted by Aileen Buckley on Feb 10 2010 9:37AM
Having the option to select between two different solutions, and having thing two settings be something you can manipulate allows the user the greatest freedom and highest level of flexibility. Because we cannot assume all people will be operating under the same use case scenarios, we have to create the software in such a way that all, or almost all, use cases can be supported.
Larger arrow heads for use with thicker lines posted by Johannes Van Der Weijst on Mar 16 2010 4:53PM
When using thinker lines you can scale-up the arrow head:

1. Double click your arrow (line) symbol in the legend to enter the Symbol Selector
2. Press the "Properties ..."-button
3. Select the "Line Properties" tab.
4. Press the "Properties ..."-button in the "Line Decorations" box
5. Press the "Symbol" button.
6. In the options box you can ajust the size of the arrow head and its color (so you don't have a black arrow head on e.g. a blue line).

This procedure is an improvement, but still does not generate well looking arrowheads, as the line still pierces through the head. A simpler solution for a common and basic cartographic operation would be welcomed! The ability to choose an arrow (line and arrow head!) of a shared color and the ability to augment or reduce its overall thickness seems pretty basic to me. A chance to improve ArcMap!
Thanks, and this is a known issue posted by Aileen Buckley on Mar 19 2010 9:23AM
Thank you for your alternate solution. Also, this is a known issue so you are not alone in desiring this software enhancement.

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