Wilbur not behaving as expected

[MrBragg]

Alright, so I was messing around trying to create some mountains using Wilbur according to the tutorial here: https://www.cartographersguild.com/s...ad.php?t=30277 I admit to shamelessly cheating and screenshotting the image for the beginning of the Wilbur section of the tutorial (step 2) and beginning by loading that into Wilbur. I'm not entirely sure which step is causing me issues (or both...), but when I try to do the precipitation erosion and incise flow steps, I end up with results nowhere near what the corresponding tutorial screenshots look like. My images look much noisier than they probably should; I've tried adjusting the parameters for the various steps and nothing seems to help. I was wondering if anyone had any insight into what is going wrong here? FWIW I'm using the latest version of Wilbur (1.89).

Here's my starting point, which matches the tutorial:


Then after the precipitation erosion step things get noisy:


And they remain noisy during the subsequent incise flow and erosion steps:


For comparison, it's supposed to look like:

[Greason Wolfe]

You might need a Fill Basins before starting any erosion steps. It isn't listed as a step, but based on the images in the tutorial, I would strongly suspect that it should be the first step after loading the image in Wilbur.

The grayscale image in the tutorial may not be of quite the same quality as the original used to create the tutorial.

How many passes are you doing?

Quick experiment gave the following results....

30 passes only


Basin fill with 30 passes after


Not sure how much help that is to you, but maybe gets you a little closer.

[Charerg]

You should also set the span (Filter->Mathematical->Span) as something other than the default (which is -1 to 1 metres), try 0 to 2000 for example. This determines the elevation of the highest and lowest points on the map. You can also use Filters->Morphological->Dilate & Erode to reduce the noise after steps of precipiton erosion.

Here are a couple of quick tutorial images from Waldronate (Wilbur's creator), they're also around somewhere in the tutorial section along with the other Wilbur tutorials from Waldronate (which are much recommended):

1st demonstrates the use of Dilute and Erode:


2nd shows instructions on how to create a volcano in Wilbur:

[waldronate]

I recommend looking at https://www.cartographersguild.com/s...ad.php?t=29412 for more information on ways to use Wilbur. The tutorial you referenced probably works as written, if you can get all of the initial conditions used by the author. You probably started with a higher-resolution image than the tutorial author did. One of the major pitfalls of the precipiton (a portmanteau of "precipitation" and "automaton") filter is that it's very sensitive to the working resolution as far as the appearance of the final result goes. It's also relatively slow to operate. That initial 10 passes of precipiton operation specified in the tutorial is there to develop flow networks that can be very quickly done by fill basins, noise, and fill basins again before the incise flow step.

The noisy little blebs that you see on your image (that look like cliffs between river areas) are diagnostic of lots of precipiton erosion without any other mitigating filters, especially when done on a high-resolution image. The precipiton filter works by randomly dropping erosion agents onto the surface and each agent pushes elevation downhill based on the difference in heights until they hit a flat spot. It's like a roller coaster ride for the little guys. Any particular point is unlikely to be hit an an agent on its initial drop, which means that pointy bits and sharp edges (those cliff edges) are unlikely to be directly hit by any agent and so will remain largely intact throughout the process. On lower-resolution images (say 256x256 as compared to 1024x1024), you will more quickly develop smooth erosion features because the impact of any single agent is greater. These days I recommend starting out with as low of a resolution image as you can tolerate and then quickly scale it up with a minimal level of filtering between each level (the Fun With Wilbur tutorial set references above describes this process in some of the elements).

[MrBragg]

Thanks for the thought everyone. I tried some of these suggestions and wanted to report back what I found.

You might need a Fill Basins before starting any erosion steps. It isn't listed as a step, but based on the images in the tutorial, I would strongly suspect that it should be the first step after loading the image in Wilbur.

This was the first thing I tried. Unfortunately, filling basins first and then doing 30 passes of precipiton (didn't realize until now that the word wasn't "precipitation"...) erosion and I get this, which still has the noisy blebs that plagued my initial attempt.

You should also set the span (Filter->Mathematical->Span) as something other than the default (which is -1 to 1 metres), try 0 to 2000 for example. This determines the elevation of the highest and lowest points on the map. You can also use Filters->Morphological->Dilate & Erode to reduce the noise after steps of precipiton erosion.

I tried these next. Changing the span unfortunately didn't seem to affect the outcome at all and I still got lots of little noisy blebs. The dilate and erode functions were interesting and helped to smooth out the noise, but those left kind of blobby artifacts (apparently I'm cursed to either get blobs or blebs...). Strike 2

On lower-resolution images (say 256x256 as compared to 1024x1024), you will more quickly develop smooth erosion features because the impact of any single agent is greater. These days I recommend starting out with as low of a resolution image as you can tolerate and then quickly scale it up with a minimal level of filtering between each level (the Fun With Wilbur tutorial set references above describes this process in some of the elements).

First of all I wanted to say that your Wilbur tutorials have been very helpful with figuring the program out; I still don't' have a great intuition for how to use the various functions to achieve the result I want, but I'm definitely learning Anyway, the screenshot image I was using was 395x395, so I downsized that by 4x to 198x198. Repeating the tutorial and then scaling back up by 4x gave something that is maybe slightly better. The noise is definitely lower frequency, which makes sense, but still doesn't exactly have smooth erosion features.

[waldronate]

I think that the original surface size is closer to 256x256 than 400x400. Doing 10 passes of precipiton erosion gets you most of the way there at that resolution, but not entirely. The tutorial does mention 'Repeat 2 or 3 times if you want". Repeating three times get pretty close to the appearance in the original image. Doing a Filter>>Morphological>>Erode (your best tool against fine-detail noise until someone implements a median filter) with a value of 1 gets much closer to the first processed image shown in the tutorial.

The picture below shows how a 256(ish) square crop from the height map shown in the tutorial looks when processed with 10, 20, and 30 passes of precipiton erosion as described in the tutorial. Below each image is that amount of precipiton erosion followed by a morphological erode (grayscale minimum over a 3x3 neighborhood). The rightmost image is a crop of the result from the tutorial at the end of the first Wilbur step.

[waldronate]

What is your goal for using this tutorial? I'm asking because there may be more effective ways to get your intended results than following an old and somewhat problematic tutorial.

[MrBragg]

Wow, the morphological filter really does a wonder on the high frequency noise at that resolution! Thanks for pointing that out

What is your goal for using this tutorial? I'm asking because there may be more effective ways to get your intended results than following an old and somewhat problematic tutorial.

To be honest I'm mostly just working through different tutorials and such to get a feel for how to achieve a given result with Wilbur, so "learning" is the only real goal at this point. I've definitely learned something from this thread, so I'd consider mission accomplished.

[Harrg]

Hellow MrBragg. Sorry that my tutorual confused you. I`m bad know english for writing full step by step guide. I made this because some people asked me how I maked my mountains.
Did you can make result that you whant? Mb I can help you?
P.S. Not worth use my toutorial like toutorial for making Wuilbur mountains, this toutorial how adopted Wuilbur mountains in Photoshop maps, like this, that I made
P.S.S. Yes waldronate was right. Original size of guide map was 256x256 px. You can take it in psd file that I added in toutorial near pdf file.

[MrBragg]

Oh no worries With the help of people here and some playing around I did eventually get things to work; thanks for checking in!