Sun, 19 Apr 2026 18:39:15 +0200

2026-04-19 Technical Tutorial: Using QGIS for fantasy maps

I have used QGIS in the past to create maps for fantasy roleplaying purposes. It is a total overkill, if you want to create a local area map. But you can have a lot of fun with it on a grander scale. For example, you can export results from Azgaar’s Fantasy Map Generator to QGIS to create nicer looking maps. Lemuria Games made a great tutorial on that for YouTube: Fantasy Map Tutorial.

The most excellent Idraluna Archives has made A Tutorial for Making Hexcrawl Maps in QGIS and a series on Mapping Fantasy Antarctica which have renewed my interest in doing something with QGIS. Since Idraluna Archives already covers using real world data to create maps for elfgames, I want to focus using procedurally generated elevation data as a basis.

In this tutorial we will be making a pretty topographic map of the overall planet and generate a regional hex map for a region of interest. This involves three steps:

1. Procedurally generating a heightmap, a biomes map, and some colorful maps,

2. Importing everything into QGIS, and

3. Using QGIS magic to generate a regional hex map.

I assume you know how to install programs on your operating system and how to run programs from the command line.

Torben Æ. Mogensen’s Planet Generator

Torben Æ. Mogensen’s Planet Generator is an excellent tool. I believe I found it via donjon. The tool is fairly well documented, so I encourage you to read the manual and play around with it yourself! Here we will be using the planet generator to create a height map, generate a biomes map, and to generate some colorful images of our planet.

To generate your first map, simply type

planet -o <filename>

The generator outputs a bitmap file named <filename>, which can be converted to a compressed image file if needed. However, it generates a different map every time the generator is invoked, the default color scheme looks way too bright for my taste, and the image is probably too small to be useful later.

The first thing we want to do is to generate the map using the same random seed every time. I found the best way to find a seed is to use the generator’s Web Interface. Just hit random until you find a seed you like. I liked 10606208 a lot, and we will be using this seed as an example moving forward. It even has the stereotypical fantasy continent in the North East!

To use your seed, run the generator with the -s <seed> flag. However, for the commandline tool, the seed it is a floating point number between 0..1. If we use the seed generated by the web interface, we have to add 0. to make it a number in the range 0..1, like so

planet -s 0.10606208 -o <filename>

We now generate the same planet every time.

Generating a color map

To change the colors of our map, we can use the -C <color map> flag using one of the provided color maps. I never liked the color maps provided by default too much (except maybe mars.col), so I wrote my own based on color gradients I found on cpt-city:

Colombia.col

Wikipedia.col

Just copy these into the folder you run the generator from. To use the Colombia color gradient, for example, use

planet -s 0.10606208 -C Colombia.col -o <filename>

Looks rather pretty, doesn’t it? The map is still quite small, however. By default, the generator outputs an 800x600 pixel bitmap. We should generate a bigger map. We should also use a different projection moving forward.

The generator creates a heightmap on a sphere and squishes (yes, that’s a technical term) that heightmap into a plane using a projection. I’d love to tell you more about projections, but I’m not that guy (of course, xkcd has a comic on that topic). By default, the generator uses the Mercator projection, which is the most commonly used projection for world maps, at least in the Western world. Moving forward, we want to use the Square projection, as the generator calls it, which is also called equirectangular projection or plate carrée, pardon my French.

To change the projection, we use the -p<projection> flag, where a letter indicates the projection we want. Note that the letter immediately follows the flag! For square projection, the letter is q, so we type

planet -s 0.10606208 -C Colombia.col -pq -o <filename>

To generate a bigger map, we can use the -w <width> and -h <height> flags to set the width and height of our image. The square projection has a ratio of 2:1, so you want your <width> = 2 × <height>, for example 7800x3600:

planet -s 0.10606208 -C Colombia.col -pq -w 7800 -h 3600 -o <filename>

There are plenty more things we can tweak here. For example, we may set the -n flag which applies non-linear scaling to the height map or the -O flag which draws the coastlines as a black line. This results in maps that are more flat near the ocean. See the manual for all options!

Excursus: G.Projections

NASA has published this neat little tool called G.Projector which lets you reproject maps into a variety of different projections. We can use this to generate some nice looking topographic maps from the color map we just generated.

The tool opens up with an open file dialog. Select the color map we just made. Next, the tool asks for the input projection and the extent of the map. Select equirectangular and do not change the extent.

You can now select any projection you want from the projections tab. Note that G.Projector overlays an outline of Earth’s coastlines by default. You can turn this of in the overlay tab. Likewise, you can select a grid size in the graticule tab or turn the grid off completely.

I’ll leave it to you to play around with this tool, since it is not really the focus of this tutorial. But I want to show you one projection: Gnomonic icosahedron.

If that rings a bell with you, you have probably played Traveller!

Generating a heightmap

Next, we want to create a heightmap. The generator gives you the option to export a heightfield which stores the elevation at given points as a floating point number using the -H flag. However, I have never managed to make this format work with QGIS. We will be generating a grayscale image instead using the greyscale.col color map.

planet -s 0.10606208 -C greyscale.col -pq -w 7800 -h 3600 -o <filename>

Make sure you use all the same options (projection, size, non-linear scaling) as with your color map, otherwise, the will not align!

Generating a biomes map

The generator can automatically generate a false color map showing the biomes of our generated planet. It does so by estimating average temperature and precipitation based on latitude, altitude, and approximated rain shadow. Pretty neat.

To generate a biomes map, we use the -z flag. I tend to generate biomes maps about one-fourth of the size of my color map, since I rarely need the fidelity. To generate a biomes map for our seed, we call

planet -s 0.10606208 -z -pq -w 1800 -h 900 -o <filename>

Note that we do not provide a color map here. It defaults back to the default color map to color the ocean. If we want a purely blue ocean on our biomes map, we may use the 2col.col color map which colors land uniformly green and sea uniformly blue:

planet -s 0.10606208 -z -C 2col.col -pq -w 1800 -h 900 -o <filename>

That’s it! Next step is to load everything into QGIS.

Excursus: Climate Simulation!?

While researching for this post, I came across an online Climate Simulator. The simulation readily accepts our bitmap heightfield!

While we can generate a biomes maps using our fractal planet generator, I thought this simulator is very cool! Especially if we want plan on having a hotter/colder planet, since the planet generator only creates biomes for an Earth-like planet.

QGIS

QGIS can be a bit intimidating if you have never worked with GIS software before. I will walk you through as best I can. If you want to learn more, there are plenty of good tutorials online with varying levels of complexity. I already mentioned Idraluna Archives. Klas Karlsson has made many in-depth tutorials for using QGIS as well.

Setting up the project

Let’s get going: Open up QGIS. Easy. But before we attempt to do anything, we probably want to save our project somewhere. I named mine tutorial.qgz and saved it to a dedicated directory.

We also want to set a different project CRS (Coordinate Reference System). The default CRS, WGS84, uses Radians as default units which are a bit tricky for what we want to do. Go to Project -> Project Properties and select the CRS tab. Search for the ESRI:53001 - Sphere_Plate_Carree CRS and set that as the project CRS.

Importing the color map

Next, we want to import our color map, so we have a reference to work from. We cannot simply load the image into QGIS and expect it to know that our image is an equirectangular projection of a whole planet. We need to tell that to QGIS. The correct terminology is georeferencing.

To import our color map open the Layer menu and select Georeferencer. A new window will open. Select open raster and open the color map. The map will show up in the previously white field.

Now we need to relate coordinates in the image to coordinate points in our coordinate reference system. Click once somewhere in the upper left corner to create a first GCP (Ground Control Point). You do not have to be precise here, as we can change the image coordinates of the GCP later! A dialog opens asking you for the coordinates of this point. Make sure WGS 84 is selected here since it works in Longitude and Latitude and it is much easier to see what happens now in these coordinates. The upper left corner of our map corresponds to 180°W and 90°N, so enter -180 in the X / East field and 90 in the Y / North field. Done! Repeat for the lower right corner, now entering 180 in the X / East field and -90 in the Y / North field. Your GCP table in the bottom of the dialog should look something like this:

Now we can modify the Source X and Source Y columns to match the actual upper left and lower right corners of the image. The image coordinates of the upper left corner are x = 0 and y = 0; and the image coordinates of the lower right corner are are x = 7200 and (somewhat unintuitively) y = -3600. Your GCP should look like this:

Next, we need to set some transformation settings.

As we do not transform the image, we may also select Create world file only. This way we do not create a new transformed raster image. Make sure ESRI:53001 - Sphere_Plate_Carree is selected as Target CRS. Click OK and close the dialog.

Now save the GCP to some file using C-s or File -> Save GCP Points as…. We don’t want to do this work again for the heightmap! Now click Start Georeferencing, close the dialog, and we are done!

The color map should now appear in the Layers panel. If you do not see the Layers panel, activate it under View -> Panels.

Importing the heightmap

Now we repeat the steps for our heightmap. Open the Georeferencer from the Layer menu. Select Create world file only in the transformation settings dialog and load the GCP points we saved earlier using C-l or File -> Load GCP Points…. click Start Georeferencing, close the dialog, and we are done already!

But wait. Our heightmap is a bitmap with 256 different grays. It is also technically an RGB image (you can see three bands in the Layers panel). We need to map the bitmap onto a true heightmap, for which the values correspond to elevation. We do that using the Raster Calculator… from the Raster menu. The raster calculator is a powerful tool that allows us to manipulate all the pixels of a raster image using a mathematical expression.

In the upper left corner of the Raster Calculator dialog you should see a list of all Raster Bands in your current project. If everything worked as expected so far, you should see three bands each for the color map and the heightmap. Before we begin, we should set a name for the Output layer in the Result Layer panel to the right. I choose elevation.tif as name for the new layer. Leave the Output format as GeoTIFF. Also, make sure the Output CRS is set to ESRI:53001 - Sphere_Plate_Carree in the Result Layer panel of the dialog:

The greyscale.col color map stores the height as 255 different gray values with the same red, green, and blue values. So we may pick any of the bands to generate elevation values. I arbitrarily picked the red band or heightmap@1. We now want to map the value of each pixel to a value between a lowest elevation and a highest elevation. Note that the generator assumes that <lowest elevation> = - <highest elevation>. We may deviate from that, for example if we wanted less water on our planet, but our generated color map would not match anymore!

To map the grayscale pixel to elevation, we first shift the value of each pixel to range between -126..129 by subtracting 126. This may seem a bit arbitrary but has to do with the fact that the Colombia.col color map does not exactly match the Greyscale.col map!

We then normalize the values to a range between 0..1 before we map each pixel onto the range we want to cover. I decided I want a minimum elevation of -8000m and a maximum elevation of +8000m. So I have to multiply the values by 16000 This is the expression I entered into the Raster Calculator Expression field:

("heightmap@1" - 126)/255 * 16000

You Layers panel should look something like this:

So far, so good. We now want to style our data a little bit. We do that by first dragging the color_map layer to the top of the Layers panel. We then go to the layer properties dialog of the color_map layer by right clicking on the layer in the Layers panel and selecting Properties. In the properties dialog we select the Symbology tab and set the Blending mode to Multiply:

Click OK to close the dialog. The color map should now look a bit darker in the main view screen. We next go to the properties dialog of the elevation layer and on the Symbology tab we set the Render type to Hillshade and the Z-Factor to 10.0 (this makes the effect more pronounced):

Looks good so far, doesn’t it? Next step is to import the biomes map.

Importing the biomes map

Importing the biomes map is as easy as importing the color map and the heightmap was. We can reuse the GCP points we saved earlier using C-l or File -> Load GCP Points…. However, the source image for the biomes map is much smaller! We need to adjust the Source X and Source Y columns to match the lower right corner of our biomes map to match the dimensions of the image (x = 1800 and y = -900):

Select Create world file only in the transformation settings dialog and and click Start Georeferencing. Done!

We could work with the raster data to create our hex map. I want to go a slightly different route though which will give us a beautifully styled biomes map for our planet as a by product!

Excursus: Biome Colors

The biomes are coded in false color in the map generated by the planet generator. There is a legend in the manual. Here I provide a table with RGB values. As you can see, each biome has a unique red value. This will be useful later!

R | G | B | Biome
105 | 155 | 120 | Taiga / Boreal forest
110 | 160 | 170 | Tropical rainforest
130 | 190 | 25 | Tropical dry forest
155 | 215 | 170 | Temperate forest
170 | 195 | 200 | Temperate rainforest
185 | 150 | 160 | Xeric shrubland and dry forest
210 | 210 | 210 | Tundra
220 | 195 | 175 | Desert
225 | 155 | 100 | Savanna
250 | 215 | 165 | Grasslands
255 | 255 | 255 | Ice

Creating a vector layer for biomes

Besides raster data, QGIS can work with vector data. A vector layer comprises a number of polygons – called features in QGIS – which have a number of fields stored in the Attribute table of the layer.

You can draw features by hand. We want to create our biome features using the raster to vector conversion, however. First, make sure your Toolbox is open. You can open the Toolbox using the button or pressing C-M-t.

In the Toolbox, search for the Polygonize (Raster to Vector) tool and click it to open the dialog. Select the biomes map as the Input layer. Remember when I said that all biomes have a unique red value? We use this to uniquely classify our biomes based on the red band of the biomes map layer. Select Band 1 (Red) as the Band number. The value is stored in a field with each feature we create. We want to give that field a descriptive name. I called it biome_value. Next, we want say QGIS where to save the vector layer we are about to create. I makes sense to store all data we will generate in the future into a single GeoPackage container. So click Save to File…, name it data.gpkg. Creative, right? Click Run, and we are done.

Next we open the properties dialog of our newly created vector layer by right clicking on the data layer in the Layers panel and selecting Properties. We want to change the name of the layer to something more descriptive, for example Biomes. We can do so in the Source tab of the properties dialog.

Every feature/biome has exactly one value attached to it. The biome_value is the red value of the color that our planet generator used. Not very descriptive going forward. We want to create a field that stores the biome name for every feature/biome. We do that using the Field Calculator:

Make sure Create a new field is checked, set the Output field name to biome_name and set the Output field type to Text (string). Next, we need to write an expression that determines the value of our new field based on the value of other fields. I have prepared an expression based on the table I provided above. You’re welcome.

CASE
  WHEN "biome_value" = 0   THEN 'Ocean'
  WHEN "biome_value" = 105 THEN 'Taiga / Boreal forest'
  WHEN "biome_value" = 110 THEN 'Tropical rainforest'
  WHEN "biome_value" = 130 THEN 'Tropical dry forest'
  WHEN "biome_value" = 155 THEN 'Temperate forest'
  WHEN "biome_value" = 170 THEN 'Temperate rainforest'
  WHEN "biome_value" = 185 THEN 'Xeric shrubland and dry forest'
  WHEN "biome_value" = 210 THEN 'Tundra'
  WHEN "biome_value" = 220 THEN 'Desert'
  WHEN "biome_value" = 225 THEN 'Savanna'
  WHEN "biome_value" = 250 THEN 'Grasslands'
  WHEN "biome_value" = 255 THEN 'Ice'
END

Click OK. If you check the Attribute Table now, every feature has a new field called biome_name. Almost magic, huh?

Do not forget to save the changes made to the layer every once in a while!

Next, we want to style the layer. Each feature/biome is shown in the same color. That’s not very useful! Let us first change the styling from Single Symbol to Categorized in the Symbology tab of the properties dialog. This way, each category of feature is shown in its own color, for example.

We now need to tell QGIS by which field to categorize the features. Set the Value to biome_name. Next click Classify to create a classification. By default, every category get its own unique color which rarely looks pretty. I have written my own style which looks somewhat naturalistic colors based off the colors used by Thorf’s Hex Mapping Tools which are itself based on the old BECMI Gazatteer style! You can find the style file here:

Biomes Style

You can simply load and save styles you like using the Style menu in the Symbology tab of the properties dialog:

Click OK and you’re done. Pretty cool, huh?

Making a local hex map

We now have a global topographic map, and a biomes map. Next we want to create a hex map for some interesting region. Browse around the map to see if anything looks interesting to you. There is an island chain starting above the Equator and going North around the Prime Meridian. That looks interesting to me.

Creating the grid

Once I find an interesting region, I typically create a layer called Extent which comprises a single rectangle delimiting the region I want to detail out. This will be useful later when we create a hex grid, for example. To do so, create a new GeoPackage layer by pressing C-S-n or selecting Layer -> Create Layer -> New GeoPackage layer… from the menus to open the New Geopackage Layer dialog.

Select data.gpkg as the File name and Extent as the Table name. Then select Polygon as the Geometry type. Click OK. QGIS will now ask you whether you want to overwrite the file or create a new layer for it. Select Add New Layer. Storing multiple layers in a single container is the advantage of using a GeoPackage file.

Next, we select the Extent layer and move it to the top of the Layers panel. We then toggle editing

Now press C-. to add a new polygon. Now select the region you want to detail by pressing left click to start and left click to finish. QGIS asks you for a feature id (fid). Leave it at Autogenerate and click OK. We now have defined our extent!

Next, search for Create Grid in the Toolbox panel and click on it to start the dialog. Select Hexagon (Polygon) as the Grid type. For Grid extent select Calculate from Layer and select the extent layer we just created. Next, spacing. Hot button topic. I will go with 30 mile hexes for now. I can subdivide them later and manually add more detail to them, for example using the method The Welsh Piper detailed on their blog. Anyway, enter your preferred spacing as Horizontal spacing and Vertical spacing and do not forget to change the units to Miles. In the field Grid where is says [Create temporary layer] we want to select Save to GeoPackage… and select our data.gpkg. QGIS will ask you a name for the new layer. I choose Grid.

Click Run and we have a hex grid!

Next, we want to style the grid a little. Open the properties dialog for the Grid layer and go to the Symbology tab. Select the Simple Fill and change the Fill style to No brush. You can leave the Stroke width as is. However, I like to set the width to a fixed value in Meters at Scale. For a 30 Mile hex, I found that 1420 is a good value.

We have achieved representational hexes! If you don’t know what that means, see this blog post by Knight at the Opera.

Going Gazatteer Style!

My goal is, however, to create a map in the style of the BECMI Gazetteers. Thorfinn Tait has lovingly recreated all (?) of them. You can see them on their website Thorfinn Tait Cartography. They also created a number of templates to use with a comercial vector graphics tool: Thorf’s Hex Mapping Tools. You can open them in Inkscape just fine though.

I have extracted a number of hex templates for use with Alex Schroeder’s text-mapper (see the documentation of the Gazatteer style here)

provide a few here:

But before we can style our map like a BECMI Gazetteer, we have to tell QGIS which hex is represents which biome. We do that using the Join attributes by location tool from the Toolbox. We want to Join the features in the Grid layer using By comparing to the Biomes layer. As Join type select Take attributes of the feature with largest overlap only (one-to-one) Next we have to scroll down to field Joined layer [optional] where is says [Create temporary layer] we want to select Save to GeoPackage… and select our data.gpkg. QGIS will ask you a name for the new layer. I choose Biome Hexes. Click Run and we have a new layer!

The first thing we want to do now is change to a Categorized style. Go to the Symbology tab of the properties dialog of the Biome Hexes layer. Change the styling from Single Symbol to Categorized and set the Value to biome_name. Next click Classify to create a classification.

Now we have to set the style for each biome. Simply double click on the Symbol you want to change to open the Symbol Selector dialog. You can do this from the Symbology tab of the properties dialog or from the Layers panel!

Ocean is easy. I choose to set it to a Simple fill with the color #50a0cd. The Savanna grassland gets a Simple fill of e6f59a. Let us do something interesting next, how about the shrublands?. I want to use steppe.svg as symbol. Change Simple fill to Centroid Fill and set the Simple Marker to SVG Marker. Scroll down until you find the field where you can select the SVG you want to use as marker:

Now set the height to the height of your hexes in meters with the Meters at scale unit selected instead of Millimeters. For our 30 Mile hexes, the size is about 48280.3 m. Click OK and you have successfully styled your first biome with a hex! Now we repeat this process for the tropical dry forests I used light_deciduous_forest.svg and for the temperate (wet) forest I used heavy_deciduous_forest.svg.

Note that in the Symbology tab of the properties dialog you can copy styles from the context menu (right click on the symbol). You do not have to enter the height again each time! Just copy the styles and simply select a different SVG for each symbol.

The Grid is probably below the Biome Hexes layer. Just drag the Grid layer above the Biome Hexes layer in the Layers panel to see the grid again!

Drawing the coastline

There is one last thing I want to do before I call this tutorial finished. Our coast looks very… hexagonal. I would love to see the original coast line somehow!

For that, we need a vector layer that tells us which parts of the map are below 0 m. We do so by reclassifying our Elevation layer into two classes, one below 0 m and one above. The tool we use is the Reclassify by table tool from the Toolbox. In the dialog, select the elevation layer as Raster layer. Now open the Reclassification table.

We want to to add two rows: One with a Minimum of -9999 and a Maximum of 0, and another Minimum of 0 and a Maximum of 9999. We can set the value of the first to 0 and the value of the second to 1:

We do not need to keep this layer and so we can use a temporary layer.

Next, we want to convert this layer into a vector layer using the Polygonize (Raster to Vector) tool from the Toolbox. In the dialog, set the Input layer to the reclassified raster layer we just created. Let us set the Name of the field to create to Land. Hit Run.

We probably want to make the temporary layer we just created permanent. Select Make permanent… from the context menu of the Vectorized layer we just created in the Layers panel. Select the data.gpkg file we created earlier and Sea/Land and the Layer name. Go to the Symbology tab of the properties dialog of the Sea/Land layer. Change the styling from Single Symbol to Categorized and set the Value to Land. Next click Classify to create a classification. I set the sea features to a Simple fill with the color #50a0cd and the land features to a Simple fill with the color #96c864. We may also choose not to display the land features at all. Simply unselect them or remove them in the Symbology tab.

Outlook

We have barely scratched the surface of what is possible using QGIS. For example, we have not yet used the information provided by the Elevation to style the hexes. We may style hexes with an average altitude above a certain threshold value as mountains. To determine the average altitude we may use the Zonal statistics tool. But that is beyond the scope of this tutorial. But I may revisit this topic in the future.

If you want to learn more about making hex maps using QGIS, I refer you to Idraluna Archives.

If you want to detail one or more of the 30 Mile hexes we just generated, I suggest you take a look at the procedure The Welsh Piper details in his Hex-based Campaign Design (Part 1) post.

I’d love to hear you feedback!

Links

QGIS

Azgaar’s Fantasy Map Generator

Lemuria Games – Fantasy Map Tutorial (on YouTube)

Idraluna Archives – A Tutorial for Making Hexcrawl Maps in QGIS

Idraluna Archives – Mapping Fantasy Antarctica

Torben Æ. Mogensen’s Planet Generator

cpt-city

xkcd – Map Projections

G.Projector

Traveller

Wikipedia – Biome

Space Calc – Climate Simulator

Klas Karlsson (on YouTube)

Thorf’s Hex Mapping Tools

The Welsh Piper – Hex-based Campaign Design (Part 1)

A Knight at the Opera – How Do You Handle the “Inside” of a Hex?

TSR Archives – BECMI Gazetteers.

Thorfinn Tait Cartography

Inkscape

Alex Schroeder’s text-mapper

The Gazatteer style for text-mapper)