Tag Archives: symbols
New shapes point symbolset
With the latest ArcGIS Online update you will find new symbols for points. The Shapes symbolset offers yet more options that you can choose from, and have been specifically designed with canvas basemaps in mind. You will find them among the list of available symbols in the ArcGIS.com map viewer and Explorer Online:
They provide some vibrant choices for your maps.
For more information see the displaying features help topic.
Default Geoprocessing Symbology
While preparing for a demonstration showcasing some new Geoprocessing tools, I found a way to have the outputs of a tool to use a different default symbol than what ArcMap assigns the result when added to the map.
To do this, in ArcMap, run the tool to get the result you’re looking for, then open the Symbol Selector (single click on the symbol in the TOC). Next, change the symbology for the output to whichever icon/color you’d like to use, here I created a photo icon. In the Symbol Selector window, click on Save As…
Next, name the newly created symbol with the same name as the output generated from the tool (ex, Photos).
Now, when you run a tool that outputs to that geometry type and name, it will default the symbology to what you created. The key is it must be the same name every time.
Introducing the Emergency Management Maps Templates
Recently, an updated version of the Emergency Management Maps template and a brand new template, the Production Mapping for Emergency Management Maps template, were released on the Public Safety Resource Center. These templates provide useful maps and production configurations that will help you streamline your emergency management map production. Continue reading
A Technique For Toning Down Your Basemaps
We’re working on some new basemap styles and capabilities that will offer additional basemap choices to create a better backdrop for certain kinds of information. The one shown below was used in our recent Super Bowl Edition FanMap:
Note that the basemap is a dark slate gray, with muted colors used throughout that allows the symbols to show more clearly, and also doesn’t compete with the primary information subject of the map – fan votes for Superbowl favorites.
Recently someone asked me how to tone down the World Imagery basemap to make their symbols “pop” and wondered if there was a way to darken things a bit. That ended up being a great enhancement request, and we’ll be adding some additional options for you to control the brightness (and potentially more) in a future update. But here’s a little trick that you can use now.
Below is our basemap with several symbols used to show the route for a cross-town cycling event. We’re using the World Imagery basemap, and the symbols just don’t seem to “pop” as much as we’d like.
The imagery basemap is very bright and competes visually with our cycling route details. We toned down the basemap, and made it darker (as shown below) to make the symbols “pop.”
We’ve exaggerated the darkness a bit to make our point, but you get the idea. The symbols are definitely more visible with the darkened imagery basemap.
Ok, so how did we do it? It’s simple and there are two approaches you can take. One is to publish an ArcGIS layer service that’s a large, shaded polygon and add that to your map, adjusting the transparency for the desired effect. Another technique is to add a polygon map note, and adjust the transparency of the note feature. Both provide the desired result, and are simple enough to do.
Below is a webmap embedded in a public website that uses the same technique to make the symbols “pop.” This map uses a ArcGIS layer service that’s a partially transparent, off-white polygon.
Authoring layer packages that look great in 3D
Often the author of layer packages is using ArcMap and 2D symbols that drape, instead of billboard, when viewed in 3D mode in ArcGIS Explorer. Here’s some great information from Mark Bockenhauer in a recent ArcGIS Desktop blog post about how to author layer packages that work well in both display modes.
New Crime Symbols Available
I know many of you who map data for law enforcement agencies struggle with finding just the right way to symbolize your crime data. Some of you customize the built-in ESRI “crime” style to meet your needs, some use simple symbols from other styles, and others design their own symbols from the ground-up. For a new demo project I’m working on, none of these options were working for me – I wanted a symbol set that looked modern, “popped” off of the ArcGIS basemaps, yet still conveyed an element of the “traditional” crime symbols we’re used to. Given that I have little artistic talent of my own, I enlisted the help of ESRI’s graphics department to design a new set of crime symbols. Together, we designed the new set of 13 common crime symbols for use in Web Mapping applications, but they work just as well in Desktop projects. Hopefully, many of you will get to see the symbols in action at this year’s User Conference, where I’ll be working at the Public Safety Showcase Theater, but even better – they’re available for download on the ArcGIS Resources section of the ESRI Mapping Center here (Note: the style file is compatible with ArcGIS 10).
For help working with Style files in ArcGIS Desktop, you can reference the help, here: What Are Symbols and Styles?
Here’s a quick look at the new crime style in ArcMap, overlaid on the World Topo map service from ArcGIS.com:
Creating custom point symbols (or bowling for symbols)
While there’s quite a few symbols to choose from in the ArcGIS Explorer symbol gallery, invariably you may need to create and add your own custom ones. Here’s a quick overview of how to do that.
We’ve chosen the World Topographic Basemap from the basemap gallery and zoomed in to the ESRI Redlands campus. There we added a note at the location of ESRI’s newest headquarters building.
Here’s the default red stickpin symbol on Building Q:
We can choose a new symbol from the symbol gallery by highlighting the note in our contents, then clicking the Appearance tab and selecting a new symbol.
If Building Q were a bowling alley here’s what we might choose (we’ve upped the symbol size a bit using the tools found on the Appearance tab).
You can create your own symbols using any image editor and then adding them to the gallery. If you are making one from scratch you’ll get the best results if you create it as a square symbol (the default size is 64 x 64 px) and save it as a PNG file (to preserve transparency around the edge of your design).
For this example we’ll create a custom symbol by grabbing an existing one and
modifying it to suit our needs.
You will find all ArcGIS Explorer symbols in the Styles folder where ArcGIS Explorer is installed. We’re using Windows 7, so your paths may be slightly different. The install folder is:
C:Program Files (x86)Explorer
The symbols are found in SymbolImages under Styles:
C:Program Files (x86)ExplorerStylesSymbolImages
They are organized by theme, and here we’ve gone to the Recreation folder where we find our original bowling symbol.
We modified the symbol slightly using Photoshop (any editor will do) and saved it as a .png file to preserve transparency. Next we browsed to the symbol at its saved location to add it to our gallery. Once added, it appears in the My Symbols category.
And here it is on our map. A beauty!
For more information see the Add a new point symbol Help topic.
Alternate Explorer symbols
Today we found ourselves in search of a symbol for a project we were working on. While Explorer has lots to choose from, none of them were exactly what we wanted. So we began a search for symbols on the Web, with the requirement being that the symbol must be in the public domain and free to use. Our search turned up several choices on Wikimedia Commons. That’s a place we sometimes forget to check, but is a valuable resource for icons, symbols, pictures, and a variety of other media. Let’s go through the steps.
Here’s our result, with the default red pushpin:
First we searched Wikimedia Commons to find a symbol we liked. Here’s one we found:
We checked the copyright information to make sure it was not copyrighted and in the public domain, and therefore ok for us to use in our project – it was. To add the image to our symbol library, we clicked on the image and copied the URL at the top of the page:
Then we right-clicked the red pushpin in Explorer and opened its properties, and chose symbol properties. We clicked Add a Symbol… and pasted the URL into the Filename input:
This placed the png into our symbol library, and automatically sized it. Here’s our new symbol in Explorer:
Tip: Creating polygon results from the measure task
This morning we had an interesting question concerning a result created from the measure task. In this case the user was measuring the area of building rooftops, and wanted to create a result using that area.
To measure area, just activate the measure task, choose the polygon tool, and digitize around the outline of the rooftop. The area measurements can be displayed in a variety of different units. Here we’ve digtized around the roof edge of a warehouse, and have come up with a figure of about 18,478 square feet.
One of the measure options allows you to create a result from the measurement (the Create Result button you see on the task). When the result was created from the area measurement above, the complaint from the user was that it “looked wonky.” We agreed. The result looked something like that below:
The reason it looked “wonky” is that the default symbol uses an outlined polygon. For a measure result we can’t control the symbol size of the outline (an oversight that we’ll fix in the next release). But the easy workaround is to choose a non-outlined symbol by opening the result property sheet, like the one shown below:
When Lightning Strikes
California has already had another bad fire year with many hundreds of fires burning throughout the state, most started by lightning. Between June 21 and June 22 there were nearly 10,000 strikes (9,927 to be exact). Here’s an Explorer view of the strikes during that period.
So how did we do this? Let’s take a closer look…
How was the lightning strike information captured? Vaisala is company specializing in a variety of real-time detection systems and services, and has established the National Lightning Detection Network (NLDN). This nationwide sensor-based detection system tracks cloud-to-ground lightning activity across the continental US, 24 hours a day, 365 days a year. While the Bureau of Land Management once had their own detection grid, the BLM now contracts out to Vaisala, using their detection grid.
The Automated Lightning Mapping System (ALMS) extension for ArcGIS was used to download the near real time strike location information from the BLM data server. Using the extension strike information can be chosen for a particular time frame and geographic extent. The data was download via the internet in shapefile format.
In Explorer we chose File > Open > Shapefiles to add the shapefile data to our map. We wanted to symbolize the lightning strikes using our own lightning symbol. We made one using Photoshop, starting by creating a new image with square dimensions (we chose 30 pixels a side) and making sure our background was transparent. We drew our lightning bolt, then saved it as a local PNG file.
The next step was to use our new symbol for the lightning strikes. Here we’ve opened the Select Symbol window.
But rather than choosing one of the existing symbols, we clicked Add a Symbol and navigated to the folder that we saved our PNG from above in, and selected our custom symbol instead.
The ESRI Wildfire Management site has more information on using GIS for wildfire management, prevention, and suppression. Also see the Adding a new symbol Explorer Help topic.
(Thanks to Tom Patterson, ESRI Wildland Fire Specialist, for providing information and data)
