Semi Random Landmass creation with Inkscape

[Savage Orc]

Hi Everyone,

I've been away from this site for a few years and recently, while working on another project in Inkscape, stumbled on a way to generate a semi random landmass that I thought I would share. I was messing around with the Watercolor filter and the filter editor and when I saw what started to happen I thought, that would make a cool map. So now I'm messing around with maps when I have some free time and I miss it.

Now, I only have some rudimentary skills in Inkscape so this isn't a tutorial on how to use this program, but just steps I used to make landmasses.
And I don't know if others already know this or there are more efficient ways of doing what I am doing, but I am having fun with it and comments are welcome. I know that you could just draw a shape exactly how you want it using the various tools in Inkscape, but for those who might not have the artistic skills or just want something a little more random, then this might be what you are looking for.

Anyway, lets get started: It is probably a good idea to save frequently in case something happens.

1. First I used the "Create Rectangles and Squares" tool to make a rectangle 600X400 pixels and deleted the fill and added a thin stroke around it. This does nothing for making the map, but kept me from working too large, making my computer work harder to render things. So you can skip this step if you want. I also used the "Create Stars and Polygons" to make a 5 sided polygon that I will use to layout the general shape of the land.


2. Then, with this polygon selected, I used the "Spray objects by sculpting or painting" tool to spray a general outline of the shape I want and filled in some of the empty space in the middle. It doesn't have to be perfect and you can adjust the tool settings to fill it in however you like. If you want to add some smaller details you can adjust the size of the "sample" polygon you first made and spray some more onto the shape.


3. Once the "shape" is complete I used the "Select and transform objects" tool to select all of the polygons that make up the land shape. Group them together to prepare for the next step.

Selected:


Grouped:


4. With the polygons grouped together (I didn't include the sample polygon, you can delete it if you want) go to Filters>Textures>Watercolor and apply the watercolor filter to your shape.


5. Then open up the Filter Editor by going to Filter>Filter Editor. The first option you will have at the top of the list is Gaussian Blur. The default Standard Deviation setting is 15.00. If you slide the bar to the left, the number goes down and your watercolor shape with go more towards the shape with all the polygons. If you slide the bar to the right, the number goes up and it will blur even more, to the point it practically disappears. Examples of a lower and slightly higher number are below, as well as the middle setting I used.

Low:


High:


Final Setting:


6.The next setting in the Editor is Turbulence. The default Base Frequency is 0.025. You can adjust it to what you think looks good. If you go to far with Turbulence you can get some very "spiky" shapes that may or may not be what you want. But try it and you can always undo it.


7. The last setting we are going to adjust in the Filter Editor is Composite. There are a couple of them, but we are looking for the one at the bottom of the list with blue bars by K1, K2, K3, K4. The default for those are K1 is .50, K2 is 1.00, K3 and K4 are 0.00. I only adjusted K1, K2, and K3 to darken up the shape and give more substance to work with.


8. Next, go to Edit>Make a Bitmap Copy to make a bitmap copy. The bottom shape is the bitmap.


9. Select the bitmap copy then go to Path>Trace Bitmap. Here I used Single Scan and Brightness Cutoff. The Brightness Threshold is 0.450 and you can adjust it up or down to see how it affects the shape. You have to have the bitmap selected and hit "Update" to see the preview change as you raise or lower the Threshold. The higher the Treshold, the more of the lighter wispy pieces of the bitmap will be added to the shape. The lower the setting the less that will be added. Once you find a setting you like, hit Apply.


10. Now if you used some higher blur and turbulence settings when using the Filter Editor you may find that you have some odd shapes sticking off your land. You may also have some small "islands" around the main shape or white (empty) "lakes" inside the main shape. So there may need to be some clean up needed. For the "lakes" you can get rid of those by selecting the land shape. Then go to Path>Break Apart, then Path>Union. That will make those "lakes" black and part of the main shape. You can add lakes later, but that isn't part of this tutorial. As for the "islands" when you first use Path>Break Apart, those "islands" will become separate from the main land and you can go around and delete those. If you wish to keep them it would be best to NOT include them in the Path>Union part above because they will cause issues with the next step. You can move them out of the way for later use so you can just select the main land and those now black "lakes" to do the Path>Union step.

Some odd anomalies that I got rid of before the next step:


Post Clean up:


11. Next we are going to use the Extensions>Modify Paths>Fractalize feature to give our shape a more natural looking coastline.

Detail Pre-Fractalize:


Detail Post-Fractalize:


Landmass now Fractalized:


12. Now you can fill in your new shape with a color, add water, Resize it to a size you want, export it as a PNG to use in another program, or use it in Inkscape to create your map.


Anyway, I hope you found this interesting. I'm going to try and use this to make a more detailed map in Inkscape. I've never done that before so I don't know how it will go. Not quite like using a raster image editor like GIMP or Photoshop, but it might be fun.

[Savage Orc]

Messing around with it more, and if you want to use less steps I created this in a few minutes by using Steps 1-4 then skipping to Step 8 and using different settings in the Trace Bitmap step. The two Islands/Continents are from the same watercolor shape above them, just with different Trace Bitmap Threshold settings.