Drawing order and join in symbology ignored

Question

Last week, when I went to export a map I've been working on, I noticed that the drawing order and other symbology settings of a layer were not being followed in my map layout. After taking a closer look, it appears that the line segment symbology shows correctly (both in the map and the layout) when I am zoomed in, but as I pan out, it changes and displays incorrectly (fragmenting each segment when the symbology should be joined and rearranging my drawing order).

Has anyone experienced this before or found a solution?

Robert_LeClair · Answer

This usually happens for one of two reasons in ArcGIS Pro:

First, your line symbol needs Symbol layer drawing to keep segments “joined” and ordered at small scales. When you zoom out, Pro has to draw many more line features at once. If your symbology relies on multi-layer line symbols (for example, cased roads, stacked symbol layers, or effects that must connect across adjacent features), the appearance can change unless you explicitly control how symbol layers join/merge across features and their internal draw order.

Try these steps:

* Select the line layer in Contents
* Go to Feature Layer tab > Drawing group > Symbology
* In the Symbology pane, open the Symbol layer drawing tab
* Turn on Enable symbol layer drawing
* Use Join or Join and Merge (and adjust symbol class order) to maintain connectivity and the intended drawing order across segments

Or reason #2 - if it's mainly wrong in the exported PDF, it may be a vector viewing/anti-aliasing artifact. Some exports look “fragmented” or appear to change when you zoom in/out in a PDF viewer because the output is vector and the viewer re-renders strokes differently at different zoom levels. You could try some of the PDF presets on the Export Map dropdown menu and see if that helps...

JonM32 · Answer

@JuliaCruz-Jones

If the lines are overlapping, or they are polygons that overlap each other in any way the symbology can get a bit funky and not look correct. I had a similar issue, and this was the reason for the symbology not drawing correctly.