Tackling the terrain of my worldbuilding project

[Rubikia]

Hi all! I have worked on this project for over a decade at this point, and I have posted a few of those maps here even, and over the last few years when I have been using Inkscape to make maps for it I have been expanding and standardising the terrain and river systems. With each new map plate I add a load of extra rivers, meaning that the main continent over time will be full of rivers.

I knew that I would like to have a relief map-esque thing for this setting too, and I had experimented with contours (left) years back which looked pants, and then I used Mazlo's mountain sets to give it that look (right), but Inkscape isn't the best programme to use set effectively, so I decided that I should move on to a programme much like many others here, the magical endless opportunities of Wilbur.



I have general ideas of where the mountains are, but I have rigid ideas of where the rivers are, so I wanted to use Wilbur to generate the mountains in their higher areas and maintain the river systems. I followed a few tutorials from the Guild, like CSU Johnsdale and waldronate's step-by-step of river masks, and I produced these black and white masks of the Land, basic hills, basic mountains, and the river mask.



I opened the land mask, and then Select>>Load Selection for the hills and Filter>>Mathematical>>Offset to 20, and I did the same for the mountains and set the Offset to 40. I then Select>>Load Selection for the rivers, inverse select, and set the Offset to -40, like in waldronate's aforementioned tutorial. This should have meant that the rivers were cutting deep into the land and mountains, at least that is what I expected.



I then Select>>Load Selection for the rivers mask, and did not invert, so that I was selecting all the land around them. I added 10% noise, and then proceeded with Precipation based erosion at 25 passes.



This looks okay, but it's not right yet. The only problem I am seeing is the dreaded blue appearing on the coasts... I am also 98% sure the rivers that I supposedly cut deep into the land aren't having an effect at all.

I then did 4% noise, 25 passes, 2% noise and another 25 passes to produce this (left), but then I went to Filter>>Mathematical>>Exponent and set it to 2 like the CSU Johnsdale tutorial (centre). I had a feeling that it was an issue selecting using the river mask, not the land mask, so I repeated the last step with the land mask (right)



Not going to lie, I'm quite sad that the rivers are going wild and aren't how I wanted them on the left! But in the middle, it's to the other extreme! On the right it is not as bad, but the blue edges along the coast are persisting, even getting rid of islands completely, and it doesn't look that good.



I'm not 100% sure what I did wrong/the best way to go forward, but I will continue trying. I suspect it is actually the offset that I set at the beginning that is wrong, so maybe I will have to experiment with it.



Anyway, this thread will cover my Wilbur escapades and fails, as well as how I expand my rivers and the terrain in general as I update the base map and create more map plates.

EDIT: I tried this process a few more times and the blue outline continues to show up, its almost as if wilbur is receding my coastlines which is unfortunate. I thought that when you have the land selected it wouldn't do that, but I guess not.