Geovisual Project Assignment @RyersonGeo, SA8905, Fall 2022
3D visualization is an essential and popular category in geovisualization. After a period of development, 3D printing technology has become readily available in people’s daily lives. As a result, 3D printable geovisualization project was relatively easy to implement at the individual level. Also, compared to electronic 3D models, the advantages of explaining physical 3D printed models are obvious when targeting non-professional users.
DEM Data to a 3D Surface: AccuTrans 3D – which provides translation of 3D geometry between the formats used by many 3D modeling programs.
Converting a 3D Surface to a Solid: Materialise Magics – Converting surface to a solid with thickness and the model is cut according to the boundaries of the 5 Transitional Regions of Ontario. Using different thicknesses representing the differences in total population between Transitional Regions. (e.g. The central region has a population of 5 million, and the thickness is 10 mm; the west region has a population of 4 million the thickness is 8 mm)
Slicing & Printing: This step is an indispensable step for 3D printing, but because of the wide variety of printer brands on the market, most of them have their own slicing software developed by the manufacturers, so the specific operation process varies. But there is one thing in common, after this step, the file will be transferred to the 3D printer, and what follows is a long wait.
The 5 Transitional Regions is reorganized by the 14 Local Health Integration Network (LHIN), and the corresponding population and model heights (thicknesses) for each of the five regions of Ontario are:
West, clustering of: Erie-St. Clair, South West, Hamilton Niagara Haldimand Brant, Waterloo Wellington, has a total population of about 4 million, the thickness is 8mm.
Central, clustering of: Mississauga Halton, Central West, Central, North Simcoe Muskoka, has a total population of about 5 million, the thickness is 10mm.
Toronto, clustering of: Toronto Central, has a total population of about 1.4 million, the thickness is 2.8mm.
East, clustering of: Central East, South East, Champlain, has a total population of about 3.7 million, the thickness is 7.4mm.
North, clustering of: North West, North East, has a total population of about 1.6 million, the thickness is 3.2mm.
The most unavoidable limitation of 3D printing is the accuracy of the printer itself. It is not only about the mechanical performance of the printer, but also about the materials used, the operating environment (temperature, UV intensity) and other external factors. The result of these factors is that the printed models do not match exactly, even though they are accurate on the computer. On the other hand, the 3D printed terrain can only represent variables that can be presented by unique values, such as the total population of my choice.
GeovisProject Assignment @RyersonGeo, SA8905, Fall 2022
When presented with this geovisualization opportunity I knew I wanted my final deliverable to be interactive and novel. The idea I decided on was a 3D printed topographic map with interactive elements that would allow the visualization of flow regulation from the Shand Dam by placing wooden dowels in holes of the 3D model above and below the dam to see how the dam regulated flow. This concept visualizes flow (cubic meters of water a second) in a way similar to a hydrograph, but brings in 3D elements and is novel and fun as opposed to a traditional chart. Shand Dam on the Grand River was chosen as the site to visualize flow regulation as the Grand River is the largest river system in Southern Ontario, Shand Dam is a Dam of Significance, and there are hydrometric stations that record river discharge above and below the dam for the same time periods (~1970-2022).
About Shand Dam
Dams and reservoirs like the Shand Dam are designed to provide maximum flood storage following peak flows. During high flows (often associated with spring snow melt) water is held in the reservoir to reduce the amount of flow downstream, lowering flood peak flows (Grand River Conservation Authority, 2014). Shand Dam (constructed in 1942 as Grand Valley Dam) is located just south of Belwood Lake (an artificial reservoir) in Southern Ontario, and provides significant flow regulation and low flow augmentation that prevents flooding south of the dam (Baine, 2009). Shand Dam proved a valuable investment in 1954 after Hurricane Hazel when no lives were lost in the Grand River Watershed from the hurricane.
Today, the dam continues to prevent and lessen the devastation from flooding (especially spring high-flows) through the use of four large gates and three ‘low-flow discharge tubes’ (Baine, 2009). Dam discharge from dams on the Grand River may continue for some time after the storm is over to regain reservoir storage space and prepare for the next storm (Grand River Conservation Authority, 2014). This is illustrated in the below hydrographs where the flow above and below the dam is plotted over a time series of one week prior to the peak flow and one week post the peak flow, and the dam delays and ‘flattens’ the peak discharge flow.
Data & Process
This project required two data sources – the hydrometric data for river discharge and a DEM (digital elevation model) from which a 3D printed model will be created. Hydrometric data for the two stations (02GA014 and 02GA016) was downloaded from the Government of Canada, Environment and Natural resources in the format of a .csv (comma separated value) table. Two datasets for hydrometric data were downloaded – the annual extreme peak data for both stations and the daily discharge data for both stations in date-data format. The hydrometric data provided river discharge as daily averages in cubic meters a second. The DEM was downloaded from the Government of Canada’s Geospatial Data Extraction Tool. This website makes it simple and easy to download a DEM for a specific region of canada at a variety of spatial resolutions. I chose to extract my data for the area around Shand Dam that included the hydrometric stations, at a 20 meter resolution (finest resolution available).
3D Printing the DEM
The first step in creating the interactive 3D model was becoming 3D printer certified at Toronto Metropolitan University’s Digital Media Experience Lab (DME). While I already knew how to 3D print this step was crucial as it allowed me to have access to the 3D printers in the DME for free. Becoming certified with the DME was a simple process of watching some videos, taking an online test, then booking an in person test. Once I had passed I was able to book my prints. The DME has two PRUSA brand printers. These 3D printers require a .gcode file to print models. Initially my data was in a .tiff file, and creating a .gcode file would first involve creating an STL (standard triangle language), then creating a gcode file from the STL. The gcode file acts as a set of ‘instructions’ for the 3D printer.
Exporting the STL with QGIS
First the plugin ‘DEM to 3D print’ had to be installed for QGIS. This plugin creates an STL file from the DEM (tiff). When exporting the digital elevation model to an STL (standard triangle language) file a few constraints had to be enforced.
The final size of the STL had to be under 25 mb so it could be uploaded and edited in tinkercad to add holes for the dowels.
The final size of the STL file had to be less than ~20cm by ~20cm to fit on the 3D printers bed.
The final .gcode file created from the STL would have to print in under 6 hours to be printed at the DME. This created a size constraint on the model I would be able to 3D print.
It took multiple experimentations of the QGIS DEM to 3D plugin to create the two STL files that would each print in under 6 hours, and be smaller than 25mb. The DEM was exported as an STL using the plugin and the following settings;
The spacing was 0.6mm. Spacing reflects the amount of detail in the STL, and while a spacing of 0.2 mm would have been more suitable for the project it would have created too large of a file to be imported to tinkercad.
The final model size is 6 cm by 25cm and divided into two parts of 6 by 12.5cm.
The model height of the STL was set to 400m, as the lowest elevation to be printed was 401m. This ensured an unnecessarily thick model would not be created. A thick model was to be avoided as it would waste precious 3D printing time.
The base height of the model was 2mm. This means that below the lowest elevation an additional 2 mm of model will be created.
The final scale of the model is approximately 1:90,000 (1:89,575), with a vertical exaggeration of 15 times.
Printing with the DME
These STL that were exported from QGIS were opened in PRUSA slicer to create gcode files. The 3D printer configuration of the DME printers were imported and the infill density was set to 10%. This is the lowest infill density the DME will permit, and helps lower the print time by printing a lattice on the interior of the print as opposed to solid fill. Both the gcode files would print in just under 6 hours.
3D printing the files at the DME proved more challenging than initially expected. When the slots were booked on the website I made it clear that the two files were components of a larger project, however when I arrived to print my two files the 3D printers had two different colors of filament (one of which was a blue-yellow blend). As the two 3D prints would be assembled together I was not willing to create a model that was half white, half blue/yellow. Therefore the second print had to be unfortunately pushed to the following week. At this point I was glad I had been proactive and booked the slots early otherwise I would have been forced to assemble an unattractive model. The DME staff were very understanding and found humor in the situation, immediately moving my second print to the following week so the two files could use the same filament color.
Modeling Hydrometric Data with Dowels
To choose the days used to display discharge in the interactive model the csv file of annual extreme peak data was opened in excel and maximum annual discharge was sorted in descending order. The top three discharge events at station 02GA014 (above the dam), that would have had data on the same days below the dam were:
1975-04-19 (average daily discharge of 306 cubic meters a second)
1976-03-21 (average daily discharge of 289 cubic meters a second)
2008-12-28 (average daily discharge of 283 cubic meters a second)
I also chose 2018’s peak discharge event (average daily discharge of 244 cubic meters a second on February 21st) to be included as it was a significant more recent flow event (top 6)
Once the four peak flow events had been decided on, their corresponding data in the daily discharge data were found, and a scaling factor of 0.05 was applied in excel so I would know the proportional length to cut the dowels. This meant that every 0.5cm of dowel would indicate 10 cubic meters a second of discharge.
As the dowels sit within the 3D print, prior to cutting the dowels I had to find out the depth of the holes in the model. The hole for station 02GA014 (above the dam) was 15mm deep and the holes for station 02GA016 (below the dam) were 75mm deep. This meant that I would have to add 15mm or 75mm to the dowel length to ensure the dowels would accurately reflect discharge when viewed above the model. The dowels were then cut to size, painted to reflect the peak discharge event they correspond to and labeled with the date the data was from. Three dowels for the legend were also cut that reflected discharge of 100, 200, and 300 cubic meters a second. Three pilot holes then three 3/16” holes were drilled into the base for the project (two finished 1 x4’s) for these dowels to sit.
Assembling the Model
Once all the parts were ready the model could be assembled. The necessary information about the project and legend was then printed and carefully transferred to the wood with acetone. Then the base of the 3D print was aggressively sanded to provide better adhesion and glued onto the wood and clamped in place. I had to be careful with this as too tight of clamps would crack the print, but too loose of clamps and the print wouldn’t stay in place as it dried.
The finished interactive model allows the visualization of flow regulation from the Shand Dam, for different peak flow events, and highlights the value of this particular dam. Broadly, this project idea was a way to visualize hydrographs, and showed the differences in discharge over a spatial and temporal scale that resulted from the dam. The top dowel shows the flow above the dam for the peak flow event, and the three dowels below the dam show the flow below the dam for the day of the peak discharge, one day after, and two days after, to show the flow regulation over a period of days and illustrate the delayed and moderated hydrograph peak. The legend dowels are easily removable to line them up with the dowels in the 3D print to get a better idea of ow much flow there was on a given day at a given place. The project idea I used in creating this model can easily be modified for other dams (provided there is suitable hydrometric data). Beyond visualizing flow regulation the same idea and process could be used to create models that show discharge at different stations over a watershed, or over a continuous period of time – such as monthly averages over a year. These models could have a variety of uses such as showing how river discharge changed in response to urbanization, or how climate change is causing more significant spring peak flows from snowmelt.
Grand River Conservation Authority (2014). Grand River Watershed Water Management Plan. Prepared by the Project Team, Water Management Plan., Cambridge, ON. 137p. + appendices. Retrieved from https://www.grandriver.ca/en/our-watershed/resources/Documents/WMP/Water_WMP_Plan_Complete.pdf
Walker, A. (April 18th, 1942). The dam is 72 feet high, 300 feet wide at the base, and more than a third of a mile long [photograph]. Toronto Star Photograph Archive, Toronto Public Library Digital Archives. Retrieved from https://digitalarchive.tpl.ca/objects/228722/the-dam-is-72-feet-high-300-feet-wide-at-the-base-and-more
by Scott Mackey, Geovis Project Assignment @RyersonGeo, SA8905, Fall 2016
Since its first iteration in 1984 with Charles Hull’s Stereo Lithography, the process of additive manufacturing has made substantial technological bounds (Ishengoma, 2014). With advances in both capability and cost effectiveness, 3D printing has recently grown immensely in popularity and practicality. Sites like Thingiverse and Tinkercad allow anyone with access to a 3D printer (which are becoming more and more affordable) to create tangible models of anything and everything.
When I discovered the 3D printers at Ryerson’s Digital Media Experience (DME) lab, I decided to 3D print models of interesting Canadian topographies, selecting study areas from the east coast (Nova Scotia), west coast (Alberta), and central Canada (southern Ontario). These locations show the range of topographies and land types strewn across Canada, and the models can provide practical use alongside their aesthetic allure by identifying key features throughout the different elevations of the scene.
The first step in this process was to learn how to 3D print. The DME has three different 3D printers, all of which use an additive layering process. An additive process melts materials and applies them thin layer by thin layer to create a final physical product. A variety of materials can be used in additive layers, including plastic filaments such as polylactic acid (PLA) (plastic filament) and Acrylonitrile Butadiene Styrene (ABS), or nylon filaments. After a brief tutorial at the DME on the 3D printing process, I chose to use their Lulzbot TAZ, the 3D printer offering the largest surface area. The TAZ is compatible with ABS or PLA filament of a 1.75 mm diameter. I decided on white PLA filament as it offers a smooth finish and melts at a lower temperature, with the white colour being easy to paint over.
The next step was to acquire the data in the necessary format. The TAZ requires the digital 3D model to be in an STL (STereoLithography) format. Two websites were paramount in the creation of my STL files. The first was GeoGratis Geospatial Data Extraction. This National Resources Canada site provides free geospatial data extraction, allowing the user to select elevation (DSM or DEM) and land use attribute data in an area of Canada. The process of downloading the data was quick and painless, and soon I had detailed geospatial information on the sites I was modelling.
One challenge still remained despite having elevation and land use data – creating an STL file. While researching how to do this, I came across the open source web tool called Terrain2STL on a visualization website called jthatch.com. This tool allows the user to select an area on a Google basemap, and then extracts the elevation data of that area from the Consortium for Spatial Information’s SRTM 90m Digital Elevation Database, originally produced by NASA. Terrain2STL allows the users to increase the vertical scaling (up to four times) in order to exaggerate elevation, lower the height of sea level for emphasis, and raise the base height of the produced model in a selected area ranging in size from a few city blocks to an entire national park.
The first area I selected was Charleston Lake in southern Ontario. Being a southern part of the Canadian Shield, this lake was created by glaciers scarring the Earth’s surface. The vertical scaling was set to four, as the scene does not have much elevation change.
Once I downloaded the STL, I brought the file into Windows 10’s 3D Builder application to slim down the base of the model. The 3D modelling program Cura was then used to further exaggerated the vertical scaling to 6 times, and to upload the model to the TAZ. Once the filament was loaded and the printer heated, it was ready to print. This first model took around 5 hours, and fortunately went flawlessly.
Cape Breton, Nova Scotia was selected for the east coast model. While this site has a bit more elevation change than Charleston Lake, it still needed to have 4 times vertical exaggeration to show the site’s elevations. This print took roughly 4 and a half hours.
Finally, I selected Banff, Alberta as my final scene. This area shows the entrance to Banff National Park from Calgary. No vertical scaling was needed for this area. This print took roughly 5 and half hours.
Once all the models were successfully printed, it was time to add some visual emphasis. This was done by painting each model with acrylic paint, using lighter green shades for high areas to darker green shades for areas of low elevation, and blue for water. The data extracted from GeoGratis was used as a reference in is process. Although I explored the idea of including delineations of trails, trail heads, roads, railways, and other features, I decided they would make the models too busy. However, future iterations of such 3D models could be designed to show specific land uses and features for more practical purposes.
3D models are a fun and appealing way to visual topographies. There is something inexplicably satisfying about holding a tangible representation of the Earth, and the applicability of 3D geographic models for analysis should not be overlooked.
GeoGratis Geospatial Data Extraction. (n.d.). Retrieved November 28, 2016, from http://www.geogratis.gc.ca/site/eng/extraction
Ishengoma, F. R., & Mtaho, A. B. (2014). 3D Printing: Developing Countries Perspectives. International Journal of Computer Applications,104(11), 30-34. doi:10.5120/18249-9329
Terrain2STL Create STL models of the surface of Earth. (n.d.). Retrieved November 28, 2016, from http://jthatch.com/Terrain2STL/
Author: CHRISTINA BOROWIEC
Geovis Project Assignment @RyersonGeo, SA8905, Fall 2016
The model displayed above is of the West Don Lands of the City of Toronto, bounded by Queen St. E to the north, the rail corridor to the south, Berkeley St. to the west, and Bayview Ave. to the east. In utilizing Ryerson University’s Digital Media Experience Lab’s three-dimensional printing technology, an interactive model providing a tangible means to explore the physical impact of urbanization and the resultant change in the city’s skyline has been produced. The model interactively demonstrates how the West Don Lands, a former brownfield, have intensified from 2011 to 2015 as a result of waterfront revitalization projects and by serving as the Athletes’ Village for the Toronto Pan Am/Parapan American Games.
Buildings constructed during or prior to 2011 are printed in black, while those built in 2012 or later are green. In total, 11 development projects have been undertaken within the study area between 2011 and 2015. Each of these development projects have been individually printed, and correspond to a single property on the base layer, which is identifiable by the unique building footprint. The new developments can be easily attached and removed from the base of the model (the 2011 building and elevation layer) via magnetic bases and footprints, thereby providing an engaging way to discover how the West Don Lands of Toronto have developed in a four year period. By interacting with the model, the greater implications of the developments on the city’s built form and skyline can be realized and experienced at a tangible scale.
Areas with the lowest elevation (approximately 74 m) are solidly filled in on the landscape grid, while areas with higher elevations (80 m to 84 m) have stacked grids and foam risers added to better exaggerate and communicate the natural landscape. These additions can be viewed in the video below.
Street names and a north arrow are included on the model, as well as both an absolute and traditional scale bar. The absolute scale of the model is 1:5,000.
To complete the project, a mixture of geographic information system (GIS) and modeling software were used. First, the 3D Massing shapefile was downloaded from the City of Toronto’s OpenData website, and the digital elevation model (DEM) for Toronto was retrieved from Natural Resources Canada. Using ArcMap, the 3D Massing shapefile, which includes information such as the name, location, height, elevation, and age of buildings in the city, was clipped to the study area. Next, buildings constructed prior to or during 2011 were selected and exported as a new layer file. The same was done for new developments, or the buildings constructed from 2012 to 2015, with both layers using a NAD83 UTM Zone 17N projection. Once these new layers were successfully created, they were imported into ArcScene.
In ArcScene, the digital elevation model for Toronto was opened and projected in NAD83. The raster layer was clipped to the extent of the 2011 building layer, and ensured to have the same spatial reference as the building layer. Next, the DEM layer properties were adjusted so base heights were obtained from the surface, and a vertical exaggeration was calculated from the extent of the DEM in the scene properties. Once complete, the “EleZ” variable data provided in the building layers’ shapefiles were used to calculate and display building heights. The new developments 3D file was then exported, as the 2011 buildings and DEM files were merged. Since the “EleZ” (building height) variable was used rather than “Z” (ground elevation) or “Elevation” (building height from mean sea level), the two layers successfully merged without buildings extending below the DEM layer. The merged file was then exported as a 3D file. Although many technical issues were encountered at this point in the project (i.e. the files failed to merge, ArcScene crashed unexpectedly repeatedly, exported file quality was low…), the challenges were overcome by viewing online tutorials of users who had encountered similar issues.
Once the two 3D files were successfully exported (the new developments building file and the 2011 building file merged with the DEM), they were converted to .STL file types and opened in AutoDesk Inventor. Here, the files were edited, cleaned, smoothed, and processed to ensure the model was complete and would be accepted in Cura (3D printing software).
At Ryerson University’s Digital Media Experience Lab, the models were printed using the TAZ three-dimensional printer (pictured below). Black filament was used for the 2011 buildings and DEM layer, and green was used for the new developments. These colours were selected from what was currently available at the lab because they provided the greatest level of contrast. In total, printing took approximately 7 hours to complete, with the base layer taking about 5.5 hours and the new developments requiring 1.5 hours. The video above reveals the printing process. No issues were encountered in the utilization of the 3D printer, as staff were on-hand to answer any questions and provide assistance. Regarding printing settings, the temperature of the bed was set at 60°C, and the print temperature was set to 210°C. A 0.4 mm nozzle was used with a 20% fill density. The filament density was 1.75 mm, and a brim was added for support to the platform during printing. Although the brim is typically removed at the completion of a print, the brim was intentionally kept on the model for aesthetic purposes and to serve as a border to the study area.
Once printing was completed, the model was attached to a raised base and street names, a north arrow, legend, absolute scale and scale bar, and title were added. Magnets were then cut to fit the new development building pieces, and attached both to the base layer of the model and the new developments. As a final step in the process, the model’s durability and stability were tested by encouraging family and friends to interact with the model prior to its display at the Environics User Conference in Toronto, Ontario in November 2016.
To improve the project, three enhancements are recommended. First, stronger magnets could be utilized both on the new development pieces and on the base layer of the model. In doing so, the model would become more durable, sturdy, and easier to lift up to examine at eye level – without the worry of buildings falling over due to low magnetic attractiveness resulting from the thicker cardboard base on which the model rests. In relation to this, stronger glue could be used to better bind the street names to the grid as well.
Additionally, the model may be improved if a solid base layer was used instead of a grid. Although the grid was intended to be experimental and remains an interesting feature which draws attention, it would likely be easier for a viewer to interpret the natural features of the area (including the hills and valleys) if the model base was solid.
The last enhancement entails using a greater variety of filaments in the model’s production to create a more visually impactful product with more distinguishable features. For instance, the base elevation layer could be printed in a different colour than the buildings constructed in 2011. Although this would complicate the printing and assembly of the model, the final product would be more eye-catching.
City of Toronto. (2016, May). 3D Massing. Buildings [Shapefile]. Toronto, Ontario. Accessed from <http://www1.toronto.ca/wps/portal/contentonly?vgnextoid=d431d477f9a3a410VgnVCM10000071d60f89RCRD>.
Natural Resources Canada. (1999). Canadian Digital Elevation Data (CDED). Digital Elevation Model [Shapefile]. Toronto, Ontario. Accessed from <http://maps.library.utoronto.ca/cgi-bin/datainventory.pl?idnum=20&display=full&title=Canadian+Digital+Elevation+Model+(DEM)+&edition=>.
Professor: Dr. Claus Rinner
SA 8905: Cartography and Geovisualization
Department of Geography and Environmental Studies
Date: November 29, 2016
Produced by: Anne Christian
Geovis Course Assignment, SA8905, Fall 2015 (Rinner)
Toronto is often seen as the city of many cultures, and with different cultures often come different beliefs. I wanted to explore the places of worship in Toronto and determine what areas have the highest concentrations versus the lowest concentrations. As I explored the different ways to display this information in a way that is effective and also unique, I discovered the use of hexbin maps and 3D maps. While doing some exploratory analysis, I discovered that while hexbin maps have been created before and 3D maps have been printed before, I was unable to find someone who has printed a 3D hexbin prism map, so I decided to take on this endeavor.
Hexbin maps are a great alternative technique for working with large data sets, especially point data. Hexagonal binning uses a hexagon shape grid, and allows one to divide up space in a map into equal units and display the information (in this case the places of worship) that falls within each unit (in this case hexagon grids). The tools used to create this project include QGIS, ArcGIS, and ArcScene, although it could probably be completed entirely within QGIS and other open-source software.
Below are the specific steps I followed to create the 3D hexbin map:
Obtained the places of worship point data (2006) from the City of Toronto’s Open Data Catalogue.
Opened QGIS, and added the MMQGIS plugin.
Inputted the places of worship point data into QGIS.
Used the “Create Grid Lines Layer” tool (Figure 1) and selected the hexagon shape, which created a new shapefile layer of a hexagon grid.
Used the “Points in Polygon” tool (Figure 2) which counts the points (in this case the places of worship) that fall within each hexagon grid. I chose the hexagon grid as the input polygon layer and the places of worship as the input point layer. The number of places of worship within each hexagon grid was counted and added as a field in the new shapefile.
Inputted the created shapefile with the count field into ArcGIS.
Used the clip tool to include only the hexagons that are within the Toronto boundary.
Classified the data into 5 classes using the quantile classification method, and attributed one value for each class so that there are only 5 heights in the final model. For example, the first class had values 0-3 in it, and the value I attributed to this class was 1.5. I did this for all of the classes.
The hexagons for the legend were created using the editor toolbar, whereby each of the 5 hexagons were digitized and given a height value that matched with the map prism height.
Inputted the shapefile with the new classified field values into ArcScene, and extruded the classified values and divided the value by 280 because this height works well and can be printed in a timely manner.
Both the legend and hexagonal map shapefile were converted into wrl format in Arcscene. The wrl file was opened in Windows 10 3D Builder and converted into STL format.
This file was then brought to the Digital Media Experience (DME) lab at Ryerson, and the Printrbot Simple was used to print the model using the Cura program. The model was rescaled where appropriate. My map took approximately 3 hours to print, but the time can vary depending on the spatial detail of what is being printed. The legend took approximately 45 minutes. Below is a short video of how the Printrbot created my legend. A similar process was used to created the map.
The final map and legend (displayed in the image below) provide a helpful and creative way to display data. The taller prisms indicate areas with the most places of worship, and the shorter prisms indicate the areas in Toronto with the least places of worship. This hexagonal prism map allows for effective numerical comparisons between different parts of Toronto.