Exploring the Thematic Capabilities of OpenJump

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Purpose

The purpose of this tutorial will be to demonstrate the thematic capabilities of the software OpenJUMP, inclusing how the program visualizes vector data and how users can add and change feature layer properties and symbologies. Basic capabilities will be shown through a series of example using data from the National Capital Commission. Additional features of the program will also be discussed. Upon learning about and exploring the software's thematic capabilities, users will become more familiar with OpenJUMP and may potentially use this open source program in the future as an alternative or a complement to other proprietary GIS software.

Introduction

OpenJUMP is an open source Geographic Information System (GIS), formally known as JUMP (JAVA Unified Mapping Platform), created by Vivid Solutions Inc. in 2002. Today, the software is developed and maintained by a group of global volunteers. The program is free to use and runs of Windows, Linux, and Mac platforms. OpenJUMP can read and write shapefiles and utilizies Open Geospatial Consortim (OGC) standards such as GML, WFS and WMS. In this tutorial, you will explore the program's capabilities in editing and symbolizing attribute data and creating maps for export.

Methods

Getting Started

The first step of this tutorial is to download the OpenJUMP software. HERE

FileDownlooad.png Figure 1. Screenshot of the JUMP Pilot Project webpage - Select "Download Latest Version" to get started (09/25/21)


Collecting the Data

The data used for the purposes of this tutorial is provided by the National Capital Commission (NCC) under the Carleton Unviersity GIS Data Use Agreement. Authorized users including Carleton students, faculty and staff can download the data from the MacOdrum Library HERE.


Data Download.png Figure 2. Screenshot of MacOdrum Library data webpage - Select the text highlighted in red to access the data (09/25/21)

Only a select few of the datasets available are needed for the tutorial. Download the .Zip files from the list below (see also Figure 3) and save them to a designated folder on your computer.

  • Activities.ZIP
  • Boundaries.ZIP
  • CanMap.ZIP (found in "Mapping" folder)

Datasets1.png

Figure 3. NCC thematic datasets available for download - Select the files underlined in red to begin download (09/25/21)


Accessing the data

To import the downloaded data, launch OpenJUMP and select the folder icon in the left-hand corner of the toolbar. In the dialog box (Figure 4), browse for the data and select the files (Activities.zip, Boundaries.zip, CanMap.zip) to load them into the project space, then click "Next". When prompted to select the type of file for each file extension, simply click "Finish" to import the data and complete this step.

DataImport.png Figure 4. Blank project in OpenJUMP - Click the folder icon circled in red, select the three .zip files shown and click "Next"

Once the data is loaded into the project, you will need to tidy and organize the feature layers. Start by selecting or 'toggling on' the layers needed for this tutorial from the list below:

Activities:

  • Picnic_Areas_2011.shp
  • Recreations_Paths_and_Trails_2011.shp

Boundaries:

  • Gatineau_Park_New_1997.shp
  • Municipal_Parks.shp

CanMap:

  • Roads.shp

SecondStepDataImport.png Figure 5. Map view in OpenJUMP - Once data is imported, organize the feature layers in the table of contents on the left (Colours may vary)

To delete unnecessary layers from the project, right-click on the layer in the table of contents and select "Remove Selected Layers". Next, determine the layers' drawing order on a map by ordering the list of layers in the table of contents. This can be done by clicking and dragging each layer to the desired position. Layers can also be renamed for easier identification by double-clicking on the layer.

Datamap.png Figure 6. Feature layer pop-up menu - Remove selected layers, view attribute data or open the style dialog by selecting the option highlighted in red


Symbolizing the Data

We will now symbolize the imported feature layers using a variety of symbolization methods available in the software. This section will primarily focus on single symbol, graduated colours, and unique values symbologies. Colour-based symbology options will also be explored to represent specific attributes. This will allow us to combine symbols with map elements to visualize selected geographic features and have the ability to create a range of thematic maps for academic or professional use.

Single Symbol (Polygons)

To change the colour of a polygon layer, simply right-click on the layer, find "Style" on the side menu, then select "Change Styles". A dialog box will appear with a number of tabs that allow you to change the visual properties of a layer. In the "Rendering" tab, you can change the fill, line width and transparency of a polygon layer. OpenJUMP offers a number of presets, or you can customize the colour of a symbol by clicking on the three dots to open the "Change Colour" dialog. A range of colour swatches are available to choose from or you can create a colour scheme using tools such as ColorBrewer [1] and input custom RBG and HEX colour codes. Once finished, select "Apply" then "OK" to close the dialog.

For this example, start by changing the colour of the Gatineau Park boundary layer (see Figure 7). Next, try changing the colour of boundary layer for the National Capital Region.

Styles.png Figure 7. Applying single symbol symbology - In the "Rendering" tab, change the fill and line colours from the presets on the right or clicking on the three dots circled in red for more options. Click "Apply" to save and view your changes

PHOTO Figure 8. Advanced colour options in OpenJUMP


Single Symbol (Points)

To change the symbol and colour of a point feature layer, open the “Change Styles” dialog box again by right-clicking on the desired layer. In the “Rendering” tab, check the “Vertices Size” box and use the sliding scale or text box to adjust the size of point features. From the “Point Display Type” drop-down menu, you can choose from shapes including square, circle, triangle, cross, star, or Bitmap. This option allows you to select an image to represent the data. The line and fill colours of the symbol can then be changed in the same manner as the above example.

Colours.png Figure 10. Point feature symbology – In the “Rendering” tab, select the option for “Vertices Size”, adjust the symbol size, and choose the display type/shape

To access more symbol options within the program, use the “VertexSymbolPlugin” tool. This tool can be accessed in the right-hand corner of the toolbar. First, ensure that the desired layer is in editable mode by right-clicking on the layer in the table of contents. Within the “Vertex Symbol Dialog” box, select from the options in the “Vector” and “WKT Shapes” tabs. Enter the size in the text box and click “OK” to apply changes.

PHOTO Figure 11. Vertex Symbol Plugin – For more point symbol options, open the dialog from the paint icon on the toolbar, choose the desired symbol, and set the size


Unique Values

To symbolize data based on unique attribute values, a colour theme will be chosen to symbolize each respective value. The number of colours will vary depending on the number of unique values in a given attribute and will allow map viewers to differentiate between different qualitative features.

For this tutorial, you will use unique value symbology to visualize the different types of trails within the area of interest. To begin, right-click on the Activities/Recreation_Paths_and_Trails layer and open the “Change Styles” dialog box. Select the “Colour Theming” tab and check the box to enable colour theming. From this step, choose the attribute “TRAIL_TYPE” from the drop-down menu and set the classification method as “Unique Value”. Then, select the colour scheme of your choice from the options in the drop-down menu. There are a number of sequential, diverging, and random colour schemes from Colour Brewer and Visual Mining Inc. The table displays the unique values and the corresponding colour as well as the label (how it will appear on the map legend). You can also use the sliding scales or text boxes to adjust the transparency and line width of the features.

DataThemes.png Figure 12. Unique Values Symbology – In the “Colour Theming” tab, enable colour theming, select the attribute ‘TRAIL_TYPE’ and set the classification method as ‘Unique Value’. Choose a colour scheme from the drop-down menu and adjust the transparency and line width highlighted in red


Graduated Colours

Graduated colour symbology can be to classify data into ranges based on a given attribute field. The selected classification method and number of classes determine how the data is distributed between the ranges and the number of assigned colours. Using the NCC data, we can symbolize the municipal parks in the area of interest by their size (hectares). First, open the “Change Styles” dialog for the layer and enable colour theming. From the set of drop-down menus, set the attribute as ‘HECTARES’ and select an appropriate classification method and range count. After this step, select a colour scheme from the drop-down menu and edit your labels to the desired number of decimal places.

Learn more about classification methods here.

ChangeColours.png Figure 13. Graduated Colour Symbology – In the “Colour Theming” tab, set the classification and range count underlined in red and choose a colour scheme from the drop-down menu. Edit the appearance of attribute labels on the map legend by double-clicking

The attributes that will be represented in this tutorial is Trail_Type found in the Activities/Recreation_Paths_and_Trails layer.

TrailMap.png

Figure 12. Shows the display options chosen for this map.

Editing the Data
OpenJump lets you alter the downloadable data to whatever fits your needs. So if you obtain new up to date information you can actually change/update the data. It is even possible to add your own point of interest for whatever needs you may have. For this exercise, we will show you how to edit this information. First you need to right click on the layer you wish to edit>select editable> then open up the attribute of the select layer you wish you wish to change. For this exercise, to show how to edit data in the attirbute table, we are going to edit the Boundaries/Regions layer. Currently there are three attributes shown in the field AGENCY; GATINEAU, OTTAWA, and MRC. For the purpose of this tutorial only want to show Ottawa and Gatineau, so we are going to replace MCR with Gatineau so that there are only two main boundaries.

EditableLayer.png

Figure 13. Red shows that editable should be selected on the layer to edit the attribute data.

EditAttributes2.png

Figure 14. Red shows the 'Edit/View Attribute' option to open an attribute table and edit it.

Editing the Data Part 2
In order to actually edit the data you need to double click on the data you wish to change, delete what is currently there, and put in the information you wish to display. Since we only want 2 attribute data categories to be shown on the map, we are going to change MRC to Gatineau. Note: All of the spelling and capitalization needs to stay the same or else the program will not recognize it. So in this case make sure that when you write in Gatineau that it is all capitalized (GATINEAU).

BeforeAtt.png AfterAtt.png

Figure 13. This top image depicts what the attribute data looked like before, on the bottom is what it looked like after.


Labeling

Labels can be used in thematic maps to describe features of an attribute such as names of provinces, parks, and water bodies. To add labels in OpenJUMP, open the “Change Styles” dialog and enable labelling in the “Labels” tab.

Symbology1.png Figure 11. Shows where in Openjump you can change the appearance of point data. The program uses very simple shapes.


Final Image

Now that we have discovered some of the basic thematic capabilities of the software, we can explore how to create and export maps in OpenJUMP. In the program’s layout view, we can view our data frame and add cartographic elements including a title, legend, north arrow, and scale. Select the printer icon in the right-hand corner of the toolbar to view your map in layout view/“Printer Setup”. Next, select the “Furniture” button to open a dialog box. Navigate through the different tabs to customize and add map elements to the print view. Before applying changes, ensure that the “Show” box is checked to make the furniture appear.

PrinterOption.png

Figure 15. Shows where you can access printer and the different options you can access to change the layout of your map.

Options.png

Figure 16, below, shows the different map elements that can be added to the final product. The 'show' box must be checked for the map element to show on the print view of the map.

Figure 16. Shows the different map elements that can be added to the printed/final map. Red shows 'show' box that must be checked for elements to show on map.

To add a scale to the map, first ensure that on the Printer Setup page, the scale is set to a nice even number that you would like displayed on the scale bar on the map. Then select the 'Scale' tab in the Furniture window and edit font sizes, fonts and other options as you'd like.

ScaleOptions.png

Figure 17. Shows the Scale Options tab of the Furniture window.

To add a legend to the map, select the Legend tab from the Furniture window and check the boxes for each layer you would like included in the legend. Format font, font sizes and other options to your liking.

LegendOptions.png

Figure 18. Legend Options tab of the Furniture Window.

Format the map however you want to your liking until you are happy with your results (Figure 16). Tip: Names of layers can be changed by double clicking on them.

FinalMap.png

Figure 16. The final map created with this tutorial: Map that shows the outdoor recreational activities that Ottawa and Gatineau have to offer.

Conclusion

From this tutorial, you have hopefully gained some familiarity with the software OpenJUMP and learned about its thematic capabilities. You will also have successfully symbolized different types of data using a selection of methods and explored how to add cartographic elements to your maps. You are now able to explore more of the capabilities in this program including plugins and use them in future mapping projects.