I am working in ArcMap 10.1. I have to represent the flow direction of a line Feature Class in a FGDB and to convert it in KML format. I have used the "Arrow Right Middle" and it works fine, as my hydro network was well digitized. However, that symbology wont translate into KML. Point symbology, on the other hand, should translate properly. Therefore, I have created points on the segments of my Hydro layer. I am looking for a way to orient arrow symbols on those points in the direction of the corresponding lines.
Thanks a lot Midavolo! Unfortunately, I don't have access to the Water Utility Network Editing and Analysis toolbars (which as you say has a Rotation to Features tool that populates a ROTATION field with the orientation of a line, which you can then use to rotate your symbols for each point). However, you got me thinking that if a tool can read the direction of the line, it's because it is inscribed in it. So I looked for a line of code that I could use in Field Calculator and found this answer given to someone else who had a similar problem: https://geonet.esri.com/thread/27393. The Python code line is 180 + math.atan2((!Shape.lastpoint.Y! - !Shape.firstpoint.Y!),(!Shape.lastpoint.X! - !Shape.firstpoint.X!)) * (180 / math.pi). It populates a field with the orientation of the line. I then proceeded to create points via Feature to Point. It turns out that KML doesn’t digest rotation if point symbols, so I had to classify the values and to attribute each class with a different arrow symbol (I have them point N, NE, E, SE, S, SO, O and NO). It’s imprecise, but it’s the solution for this project.