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Monday
Oct222012

Introducing Cartographica 1.4: Snapping Functions

Cartographica has had the ability to add and create new features for a while now, but new in version 1.4 are the snapping tools, designed to make the Add Feature process simpler and more efficient. Snapping tools make it easier to draw point, line, and polygon features by automatically connecting to Vertex, Edge, or Grid features on a layer. That is, if your goal is to create a new layer, or to update an old layer, then using the snapping tools allows you to more easily draw the new features. We can illustrate with an example.

In the following example you have a street layer from Lexington, Kentucky. The street data was collected from the U.S. Census 2000 Tiger/Line Files, but is downloadable by click on this link, download streets data . The street layer is incomplete due to the demolition of an old public housing complex that has since been reconstructed. During the rebuilding of the housing complex the street network was changed and redesigned. Fortunately, you can easily update your street layer by using newer satellite imagery and the snapping tool to redraw the street network.

Begin the example by importing the Lexington street file by choosing File > Import Vector Data. Also, add the satellite imagery by choosing File > Add Live Map.

After the data are visible in the Map Window zoom in to the area east of downtown Lexington that appears to have an incomplete road network. See below for the area of interest. We are interested in the area in the center of the map.

A closer look at the target area.

You can complete the street network by first adding a new layer by choosing Layer > New Layer (Move the new layer to the top of the layer stack). Choose Edit > Add Feature. You will be prompted to select the type of feature you would like to add. Select Line. The Editing Options window will appear. The Editing Options window has two options within it: First, the Snap to drop down menu allows you to select the type of snapping method you would like to use. The Vertex option allows you to snap to any vertex, or line end point. The Edge snap option allows you to snap to edge of any line or polygon edge, and finally the grid option allows you to snap to points that on a grid. Second, the snap distance is a parameter that defines how sensitive the snap feature is when snapping to any of the options listed above. For example, if the snap distance is set to 10 meters and the cursor is 15 meters from a vertex then the snapping function will not snap. Below is an image of the Editing Options window. 

Change the Snap to menu selection to Vertex. When you select the Vertex option a new pane will appear within the Editing Options window. Here you are able to select the layer that you would like to snap to when adding new features. Select the Street layer. The Snap Distance will automatically update (The automatically updated snap distance is fine for now). You are now ready to begin adding the new line features. To add points hold down the option key and click near the end point of a line feature on the street layer and draw a new street making sure to trace the streets in the corresponding satellite imagery. After you have drawn the new street press the return key. See below for an example. You should have noticed that when the snap function is working the cursor turns a bright green color. 

To continue adding new features choose Edit > Add Feature and then draw another new street. Repeat this process until you have completed the street network in this area of Lexington. Below is an example of the new layer. Note: the layer has been renamed Aspendale_Streets.

 

 

The final step is to merge the Streets and Aspendale_Streets layers to create a single layer that includes the updated street network. The updated layer will contain all of the streets from both layers and the corresponding attribute data from the original street layer. This is advantageous because all of the fields that are contained within the street file (i.e. the street name, speed limit, address, etc.) will be included in the new layer. This will allow you to manually update all of these atributes on the new Aspendale_Streets that have been drawn. The same method can be used to update any street file and allows you to continually update your data to real-time accuracy. To merge the layers first select each layer in the Layer Stack using command click. Choose Layer > Merge Layers. The following window will appear.  Set up the window to match the image below and then click consolidate. The final output will be a single layer that includes the data from both layers. 

Final Map with Consolidated Street Networks.

Monday
Oct222012

Introducing Cartographica 1.4: Layer Styles and the Uber Browser

The Layer Styles Window has been enhanced for version 1.4. The User Interface is similar, but includes several new or upgraded functions. New functions include additional editing capability on both lines and patterns for layer features, enhanced management of feature labels, new line and fill patterns, and integration with the Uber Browser. The new line and pattern styles have variable colors and can be used through drag and drop.

Also new to version 1.4 is the Uber Browser, which is designed to enhance your ability to edit and improve your layer styles. The Uber Browser is a collection of libraries that contain point, line, and pattern symbols, bookmarks, and color palettes. Each of the libraries is included with several stock items. However, the libraries can be added to, which allows you to create a collection of symbols and color palettes that you can continually refer to.

For this post we are using data from DC GIS. Click on the following links to download the data. Washington D.C. Basemap (Census tracts), DC Metro Lines, and DC Metro Entry Stations (points)

After you download the .zip files import the .shp files using File > Import Vector Data .

Start by editing the styles for the Metro Lines layer. You want to use something other than the standard line symbol to represent the Metro Lines. To accomplish this you can use the Uber Browser. Choose Window > Show Uber Browser and select the Line tab. Drag and drop the Freeway Under Construction symbol to the Metro Lines layer in the Layer Stack. See below for the Uber Browser.

 

You want to identify the metro lines by their color. In Washington D.C., the metro lines are blue, red, yellow, orange, and green.Double-click on the Metro Lines layer in the Layer Stack. Change the Based on menu to Name and then click on the Gearbox and select Distribute Unique Values. For each Metro line change the fill color to a color that matches the Metro’s name. This is done by individually selecting the Metro Line items in the Layer Styles table and then clicking on the Fill box and selecting the color. See below for an example of the Layer Styles window. 

 

You may also want to change the Metro Stations symbol. Double-Click on the Metro Stations layer in the Layer Stack. Click on the Symbol box to bring up the Uber Browser. Click and drag the Metro symbol to the Symbol Box and uncheck the Stroke box. Change the symbol size to 2 and press return. See below for the Uber Browser and Layer Styles Window. Note:  Your Uber Browser will most likely not have as many User symbols as what is shown below, including the Metro stations symbol. To add new symbols to your library find a symbol using an internet image search, save the image, and then click Add in the bottom left of the Uber Browser window. Select the Image and then click ok. The new symbol will be added to your library.

See below for the final map.

 

Friday
Oct192012

Cartographica 1.4 is now in beta

We are very pleased to finally make available the first release of 1.4, our largest version of Cartographica to date. Please read these notes if you choose to use this beta version of the software. We will be following up this post over the next few weeks discussing the new features and capabilities of Cartographica 1.4.

Beta Test Warnings

Warning: Although we have done extensive internal and private beta testing, it is important to remember that this version of Cartographica is still considered to be in testing. Please make sure that you have files that you are working on with 1.4 backed up sufficiently that you can recover from a catastrophic data loss due to file format incompatibility, erroneous data, or the or other potential errors.

Talking about 1.4

Cartographica 1.4 contains a wide variety of new features, user interface enhancements, performance improvements, and new file format support. Over the next few weeks, we will be posting new information on our blog and tweeting new information as well as making more information available on our website about 1.4 and the exciting new changes contained herein. These release notes will contain many individual feature but do not serve as sufficient documentation for how those features are used.

We welcome input from all of our customers and potential customers during this testing period, through email to support@cluetrust.com as well as via our web support site.

We would also like to encourage the sharing of opinion, feature ideas, and usability issues on our forums at our support site. This is the home of our knowledge base and is a good jumping off point if you run into problems or would like to make a suggestion.

During this period, we will be collecting data about the functioning of the software, some of which will be sent whenever the software starts, and some of which will be sent only upon your request. If you encounter a crash, please send in a little detail on what was happening at the time of the crash. If you include your email address, we will try to follow up with you when a fix is available or if we need further information.

OS Compatibility

Cartographica 1.4 requires Lion or Mountain Lion (10.7.5 or 10.8.1) or more recent in order to function correctly. We take the process of removing support for older versions of the OS very seriously, but there are many new features that we could not reasonably support on versions prior to 10.7. We have opted not to move to 10.8 as a requirement, due to the lack of support for the popular 2008 MacPros. At this time, customers using OS 10.6 will need to remain on the 1.2 versions of Cartographica, which will be maintained for at least six months. This includes fixing of significant bugs, but does not include the introduction of new features. We will continue to test for basic forward and backward compatibility between the 1.2 versions and the 1.4 versions.

Keys

Cartographica 1.4 uses the same keys as all previous versions of Cartographica. However, we have made some modifications to the verification system and therefore it is more important than previously to have your name and company name exactly as it was on license that you were granted either during the evaluation period or when you purchase the software. If you have trouble getting the software to recognize your valid key, please visit our lost key page and request that your key information be resent to you. This is the same information the Cartographica uses to determine the validity of your key and therefore if you put the information in exactly as it is sent to you, you should not have any problems.

If you do experience problems with the new key verification system, please let us know. We are performed extensive automated testing on this, we realize is an irritating element of the software and we want to make sure that operates as smoothly as possible.

If you're running both version 1.4 and the prior version of Cartographica, newly verified keys will work appropriately with both.

Compatibility with prior versions of Cartographica

We've gone to great lengths to ensure compatibility both forward and backwards between versions of Cartographica. Map sets that are written with versions 1.4 should be readable with both versions 1.4 and 1.2.10. All map sets that do not contain WFS layers or grid layers will be compatible with versions back to 1.2.9. We expect to release version 1.2.10 by the time that first and 1.4 is released, and it is also available as a direct download and using our RSS feed for test versions.

Changes made to styles will generally be visible in version 1.2.9 and above, with the exception of the new style types for lines and the new pattern fill styles. If you load a layer containing those into 1.2.x, the new styles will be appropriately ignored. If, however, you save the files using 1.2.x, the line and pattern styles will be eliminated during the same operation.

Downloading the beta

Cartographica betas will be available for direct download or available by setting your Cartographica software update preferences to Beta or Development.

Beta information is available on our beta page and release notes for 1.4 will be updated regularly.

Wednesday
Oct102012

Saving Time by Using AppleScript 

AppleScript can make life much easier when performing repetitive tasks. Recently we had an issue with a customer needing to automate the Count Points in Polygons tool across a number of point layers. The process was taking a long time due to the sheer number of point layers being aggregated. To automate the process we wrote a script that will count points from multiple point layers and automatically add new data fields to the polygon layer. The new data fields will be labeled to match the name of the point layer being aggregated.

Here, I'll show an example of this using crime data from from Washington D.C. (The data are available for download at DC GIS). We'll start with the crime data, downloaded from DC GIS, and block group polygons, downloaded from the U.S. Census Bureau. Import the data by choosing File > Import Vector Data. Note that if you download the crime data from DC GIS you will need to create new layers from selections for each of the crime types. Also, note that you can use the script in the example below on any set of point and polygon layers. So if you have point layers you want aggregated to one of your own polygons layers then you can use the script in the exact same way as shown in the example.That is, the script is not written only to be used with data in the example below. 

Cartographica offers a couple ways to complete this task of aggregating points to polygon features. First, you can choose Tools > Counts Points in Polygons. When you have a large number of point layers you will need to perform this task repetitively for each of the point layers that you would like to have aggregated to the polygon layer. When you have many point layers to aggregate, this process can be time consuming. The second option is that you can choose to perform the task by running an AppleScript that will automatically perform the task for you. 

Running the Script

The script is available by the following the link. 

To run the script

1. Make sure your Map window is frontmost in Cartographica

2. Double-click on the script file to open AppleScript Editor

The script we have provided has two parts needing mention. The first part is the script for the Standard Utilities. The Standard Utilities are some additional functions that you can copy and use in your own scripts to handle choosing layers from a list, creating unique layer and column names, and doing numeric conversion. 

The second part is at the bottom of the script where there are commands that performs the repetitive count points in polygons task. The commands are shown below. The first set command tells Cartographica to create a selection box for the point layer that you want aggregated. The second set of commands tells Cartographica to create a selection box fot the polygon layers that you want to have points aggregated on. The final command repeats the process for all selected point layers and adds a count field to the selected polygon layer that contains the original point layer's name. 

tell application "Cartographica"

set selectedLayers to my chooseLayers("Choose the Point layers", the document of the front window, 1, yes) 

set chosenLayers to my chooseLayers("Choose the Polygon layer", the document of the front window, 5, no) set polyLayer to item 1 of chosenLayers

repeat with targetlayer in selectedLayers

add point count polyLayer counting targetlayer column name (name of targetlayer

end repeat

end tell

3. Click Run

After clicking run the program will prompt you with selection boxes. Be sure to select the point layer like shown in the image below. Once you select the point layers click ok. 

After you select the point layers you will be prompted to select the polygon layer that you want the points aggregated to. Select the polygon layer and then click ok. 

The result of running the code should be new fields with names corresponding to the aggregated layer. See below for an example. 

Monday
Sep172012

Negative Buffering in Cartographica

Buffers have many applications for users of GIS. A buffer is a polygon that is drawn at specified distances around a set of point, line, or polygon features. Buffers are often used to indicate the proximity of a feature to other surrounding features. For example, school officials in one community wanted to know which schools were within 500 yards of parks due to increased reports of students skipping school in those locations. 

There are different types of buffers, but the most common method is the Uniform Width Buffer. This method identifies areas that are specific distances from a set of features. In the uniform width method the uniform width is applied to all features in a dataset, or to a number of selected features from a dataset. 

A useful variant of the Uniform Width Buffer is the Negative Buffer, which is exactly the same as Uniform Width Buffering except that the buffer distances are negative values. Negative buffering is only used with polygons because points and lines have no interior space that can be used to take on negative distance buffers. Polygons on the other hand have interior space that is capable of containing negative distance values. Negative buffers are used to indicate distances toward the center of a polygon from the boundary of the polygon. 

Use the following dataset to follow along with this example. 

Parcels Dataset

Streets Dataset

Import the data by choosing File > Import Vector Data. For the scenario in this example we have two datasets. One represents a series of polygons for property parcels in a city neighborhood, and the other represents the streets in those neighborhoods. The city needs you to create two polygon layers one representing a 24 foot easement from the centerline of each street and a second polygon representing a 3 foot interior utility easement within each parcel. 

Start with the Street Buffers. Begin by selecting the Streets layer in the Layer Stack. Choose Tools > Create Buffer for Layer's Features. This will bring up the Buffer Window. The Uniform Width option will be selected. Type in 24 and then change the metrics menu to feet. See below for an example of the Buffer Window and the output. You can change the color scheme for the Streets Buffer layer by double-clicking on the layer in the Layer Stack and then changing the fill and stroke color. For the map below the opacity was set to 0%, the stroke color was changed to blue, and the line width was changed to 3. 

Buffer Window

Uniform Width Buffer for Streets Layer

Negative Buffer for Parcels Layer

The negative buffer in this scenario represents a 3 foot utility easement that is in place to ensure, among other things, that utility vehicles can get between houses if necessary. The city wants a polygon layer representing these easements. Select the Parcels layer in the Layer Stack and then&nbsp;<strong>Choose Tools &gt; Create Buffer for Layer's Features</strong>. &nbsp;Again, the Buffer Window will appear. This time type in -3, change the metrics menu to feet and then click Buffer...Change the color scheme for the Parcels Buffer Layer by double-clicking on the layer in the Layer Stack. In the map below the fill color was eliminated by changing the opacity to 0%, the stroke color was changed to red, and the line width was changed to 1.5.