Mapping Center

I was recently asked to lend a cartographic hand to a project my agency is working on. I work for OregonMetro (the Metropolitan Planning Agency in the Portland, Oregon area) and among other things, we are charged with planning the future of the region. One of the facets of the planning program involves helping the 25 cities in our jurisdiction collaboratively plan for future growth. We have identified 39 urban centers and we defined a list of urban amenities that have been shown to have a positive impact on residential pricing and convenience or family-oriented amenities. These include the following: Read More...

Last week we received a request for blog entry on a 3D effect we could provide for displaying building footprints using cartographic representations. The most common, and simplest effect is to add a drop shadow like what is shown in the image to the right. Read More...

One of the most frequently recurring topics on Mapping Center is what to do with stacks or clusters of point features on maps. In August 2007, I wrote a blog posting on how to use Maplex to display coincident points, and this worked for some scenarios, but not all. Read More...

Not too long ago we received a question on Ask a Cartographer about symbolizing polygons with a scalloped edge (like the old ArcInfo hardwire line symbol). Hoping to do better (scallop lines were a nice idea, but they didn't always turn out as good as I would have liked, so I rarely used them), I started experimenting with the options in representation symbology. I'm happy to report that there is a better solution. Read More...

Cynthia Brewer’s new book titled Designed Maps: A Sourcebook for GIS Users is a companion piece designed to compliment the highly successful Designing Better Maps: A Guide for GIS Users published by ESRI Press in 2005. The goal of the book is to offer a graphics-intensive presentation of published maps, providing cartographic details that will prompt GIS users to think about their own maps and how to improve them. Read More...

The map excerpt shown at right (click on it to see the details) shows an example of hollow cased roads.  The map is from a mosaic of USGS DRG image files.  The map specification requires that the cased road symbol contains a transparent gap.  The examples shown below were created with ArcMap 9.2 and used cartographic representations to re-create the effect on the USGS DRG map. Read More...

A number of maps, particularly those geared towards outdoor tourism, rely on a convention that uses standard icons to list the services or amenities that are available at some place on the map. Using cartographic representations simplifies what used to be a rather unwieldy task from the perspectives of data modeling, data management, and symbology. Read More...

Dash-dot line symbols for polygon outlines should be displayed in a way that consistently shows the pattern of dashes and dots and clearly shows the shape of the polygon. In ArcGIS, a multi-layer line symbol is required. One layer is a cartographic line symbol with a dash pattern.  The second is a marker line symbol that shows a marker (the dot) with a complementary pattern to the dashes. Read More...

Indicating that a street is one-way and which way is valid to travel was a lot harder than it should have been prior to version 9.2.  At 9.2, the new representations symbology makes this a much faster and easier task.  To create this effect, you will need to have your street line data stored in a geodatabase which is a requirement for using representation symbology.

You will also need to have a field in your data that indicates whether a street is one-way. This also depends on the digitized direction of the street lines to align the arrows in the correct direction. If your streets are not digitized correctly, you can edit them by selecting each feature, set the Edit task to Modify Feature, then right click on the feature and choose Flip. Read More...