Optimizing map symbols for performance

By following certain design considerations, you can create symbols that maintain a better level of display performance. The type and complexity of each symbol you choose has a direct effect on map drawing performance, in addition to exporting, printing, and serving maps.

Below are some guidelines for maintaining performance when creating symbols for your map.

Marker symbols

To maintain good drawing performance with marker symbols, you should

Line symbols

Line symbols can be somewhat problematic when it comes to keeping their drawing performance at respectable levels while getting the detail or cartographic quality needed for your map. Of course, simple line symbols are the easiest answer when you want to reduce display times; however, these offer few options for diverse symbology other than thickness and color.

Cartographic lines, which are the most commonly used line symbol, can get relatively sluggish as more options are added. For example, adding a pattern template can result in more than double the drawing time as that of a solid cartographic line symbol. If you add an offset value or increase the width, the time to refresh the layer may double yet again. When it comes to line symbols, using fewer options will help reduce your display times.

One of the easiest ways to improve performance when drawing lines is to utilize line symbols from the ESRI_Optimized style, which contains symbols designed to perform better while appearing similar to their counterparts within the default ESRI style. The line symbols in the ESRI_Optimized style use fewer layers and reduced widths to improve performance. To learn more about working with line symbols in the optimized style, see Creating line symbols.

Here are some guidelines for maintaining good drawing performance with line symbols:

Polygon symbols

One of the easiest ways to improve performance when drawing polygons is to utilize fill symbols from the ESRI_Optimized style, which contains symbols designed to perform better while appearing similar to their counterparts within the default ESRI style. The symbols in the ESRI_Optimized style use fewer layers and reduced widths to improve performance. The picture fill symbols use .emf files versus the bitmaps that are used in the default style. To learn more about working with fill symbols in the optimized style, see Creating fill symbols.

Here are some guidelines for maintaining good drawing performance with polygon symbols:

Other symbology considerations

Other symbology techniques, including symbol level drawing and variable-depth masking, can greatly degrade drawing performance because of the additional processing required to display their effects. For example, symbol level drawing allows you to specify the order in which symbols and symbol layers for multilayer symbols are drawn on your map—overriding the default ArcMap drawing sequence. Masking is often used to clarify the legibility of a map that is densely packed with text and feature symbology.

For best practices on how to create and use these techniques effectively, see What is symbol level drawing?, Using masking, and Feature Outline Masks (Cartography).


8/2/2012