# Mapmaking Discussion & Philosophy (WIP/Critique) > Regional/World Mapping >  Editing a world map

## Deadshade

Greetings cartographers

This is my first post here because I need some general advice.
I have always liked creating maps in fantasy setting but ... manually.
Today I decided to try the next step which is using a software.
So I took on of my maps, transformed it in .bmp.
Then I selected Wilbur because it is this kind of maps I had in mind.
Read the .bmp in Wilbur and wanted to experiment.
My problem is three fold :

1) I couldn't find a tutorial for Wilbur. The number of commands and options is astronomical so that finding out how it works by experimenting is out of question. Does a tutorial exist ?
2) My target is to take the outlines of the continents&isles I created and put textures/elevations on it. Is Wilbur the right software ?
3) Is it posssible to define just a contour map and to fill it inside (mountains, lakes, forests, cities, deserts) so that the coasts become fractal, the mountains appear with different heights etc and choose the colors ?

I apologize for what may seem super newbie questions but that is what I am.

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## Midgardsormr

There are some tutorials for Wilbur at the bottom of the official download page here: Current Wilbur Version

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## Corilliant

Welcome  :Very Happy:

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## Deadshade

> There are some tutorials for Wilbur at the bottom of the official download page here: Current Wilbur Version


Thanks. I have already read that but this is not a tutorial. This is an example of creating a map using perhaps 1/100 of the available options.
I meant a true tutorial explaining how the commands in the software work.
For example : I have an island, how do I create a mountain in the middle of it ? Or how do I color the seas blue ?

Also there is perhaps a better adapted software. Time and money is not an issue for me. I mostly need something that I can learn to use and that does what I'd like to do e.g fill up land masses with mountains, rivers forests and deserts.

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## Midgardsormr

So you're not looking for a tutorial, you're looking for a manual. Give it some time and Joe will be by to help out. He goes by Waldronate here.

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## waldronate

The documentation file at the Wilbur home page is a little out of date, but it covers most of the basic features of the software. The way I see your problem, though, is that you're asking "how do I do this to my map" and the documentation covers more along the lines of "here's what the software feature does".
http://www.cartographersguild.com/ma...-wilburia.html and http://www.cartographersguild.com/ma...und-lands.html have examples of using an outline and mountain mask to generate results in Wilbur (the second one with a fairly detailed tutorial).

http://www.cartographersguild.com/so...sting-map.html may offer some suggestions for your first case. Another technique is to use the lasso tool to select the area at the base of the mountain(s) and then use Filter>>Fill>>Mound with Operation Add to fill the area.

Changing the color of the ocean depends on the shader that you're using. Some shaders have no notion of "ocean" at all. For the basic Wilbur shader, it would be Texture>>Shader Setup, Altitude page. The Color List button under "Sea" controls coloring of all areas on the land below "Sea Level".

Changing a contour map to a height field is the same process as described in the CSU Johnsondale tutorial, except that you convert each contour level to a solid mask. There are some examples of that process at the guild, I think.

Note that asking questions about Wilbur's operation is an excellent option, as I have it on good authority that the author of the software will sometimes answer such questions.

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## Deadshade

> Note that asking questions about Wilbur's operation is an excellent option, as I have it on good authority that the author of the software will sometimes answer such questions.



Many thanks Waldronate. Most kind from you.

You exactly hit the nail on the head - my problem is indeed "How do I apply the fractal Tools on a *preexisting* map ?"
In the meantime I learned a lot and am much better able to explain what I want to do than I was yesterday.

First I gave up on Wilbur as it is indeed rather difficult and too full of concepts I am not really familiar with.

I then settled on Fractal Terrains 3 and I can already use it reasonably well (have still difficulty to understand how the selection buttons work and what the options do but ....)
So as I have a PNG file of my map and can transform it in any reasonable format, I thought that my problem was solved because I only had to load my file into FT3 and then work it with the Tools.
Seemed simple enough untill I realized that while FT 3 can export in about any format, it can import basically nothing and in any case not PNG.

I spent then several hours trying to load the PNG in Wilbur (who can apparently read it but I am unable to edit it there by tracing f.ex the contours etc) then saving it with all possible extensions and then trying to load it with FT3.
All attempts failed but one (when i used the format 8 bit .bmp file) where something appears in FT 3 but it is so distorted and scrambled that I can't use it.

So basically now my question is clearly formulated : How can I transfer map contours contained in a PNG file into FT 3 ?
Alternatively I could just use the coordinates and recreate the contours directly in FT3 but I have found no fast way. Clicking on raise altitude finishes to make appear a piece of the contour in about 2 minutes on a length which is perhaps 1/500 of the total coast length so that I would spend more than 17 hours just tracing the coastlines. This is definitely too much. 
Isn't there a way to trace a coastline in FT 3 directly in less than 1 hour ?

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## waldronate

I'm not sure what your original image looks like. A sample of that image (or even the whole image, if you're willing) would be helpful.

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## Deadshade

> I'm not sure what your original image looks like. A sample of that image (or even the whole image, if you're willing) would be helpful.


Sorry I don't know how to post a picture but it probably doesn't matter as I only need to find a succession of transformations which start with a PNG (or other usual) format and finishing in FT3 where the coastline should be conserved. Nothing else matters as I will recreate the details (rivers, lakes, mountains etc)  anyway so that if it is destroyed by the transformations, it is not a problem.
To get an idea, it is basically a planet with a perimeter of 11 000 miles (about half Earth) where between latitudes of about 50° and - 50° and longitude -60 and + 60 lies an island system. The island system is composed of 4 large islands (the largest being ~ 1000x1000 miles) relatively near to each other and a dozen of smaller islands around. Everything else is sea. I will perhaps add ice caps but this is irrelevant for the moment.


It is because I have an island system that the total coastline is relatively long and I need that it be conserved before starting editing.

As I said above, surprisingly the PNG is conserved (with false and strange colors) and clearly visible when loaded into Wilbur but I am absolutely unable to edit anything.
On the other hand I am able to edit in FT3 but I am unable to transfer the coastline into it.

EDIT :
Ah I forgot. The projection I am working with is equirectangular what is called "flat world" in FT3. It was precisely to avoid distorsions at higher latitudes that I concentrated my landmasses between +50 and - 50.
And so I am stuck.

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## waldronate

On Reply, there's a "Go Advanced" button that lets you upload images.

Mostly, I'm looking for a description of the resolution of your PNG (pixels wide and high) and approximate size and placement of land masses (you have that here). The attached tutorial makes a few assumptions in that regard.

Make sure that you don't confuse the "planar world" and "flat world" items in the new world wizard. The planar world is exactly that: a flat plane for which the notion of "projection" is meaningless. The flat world is a spherical one that starts out at 0 altitude everywhere (it sets worldwide editing roughness to 0, if I recall correctly). This spherical world can be viewed in many projections and all are equally valid. The equirectangular projection is a special case projection of a sphere with a simple n:m angle (latitude, longitude):pixel relationship; the planar world is a literal flat area with a n:m linear distance:pixel relationship.

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## waldronate

> What I take from this is that I can exclude the use of Wilbur for coloring tasks if I want to get realistic latitude and altitude colors.


Correct. You can get interesting results with the Wilbur shader as-is, but not correct ones. The linear blend is what kills it (e.g. a bright blue is RGB(0,0,255); if it's present for land and the latitude shader fails to fire, then the result will be RGB(0,0,255)*0.5+RGB(0,0,0)*0.5=RGB(0,0,127), or a dark blue. The system needs some better logic for handling colors. It just takes some programming time.

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## johnvanvliet

i only use wilber to export a 16 bit png DEM image

all the coloring is done with other software

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## Azélor

I tried to follow some of the conversation and I must admit it's quite complicated. 
But have you ever considered using a shader of 4 parameters (C,M,Y,K) instead of 3 (R.G.B)? Or more parameters if that is possible. 
It could increase the possibilities maybe.

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## waldronate

The CMYK color space is intended for print applications; RGB is intended for driving a color monitor (not that there is a single "CMYK" or "RGB" color space, but those are the basic intent of the two processes). Neither is a perceptual color space such as HLS or others defined for the purpose of being easy for humans to reason about. The choice to use the RGB color space usually comes down to convenient hardware and/or operating system support.

The problems of the Wilbur shader's blending operation are quite well known (to me, at least). It's probably not going to get fixed any time soon. It's far more likely, in fact, that new shaders such as an equation or tree evaluator will appear in the unlikely event that I get some time.

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## su_liam

HLS would be an improvement, but CMYK is actually a smaller gamut. It's really easy to make a muddy mess. You need CMYK for printing, but it has little utility beyond that.

Considerably ninjaed!

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## Deadshade

> Correct. You can get interesting results with the Wilbur shader as-is, but not correct ones. The linear blend is what kills it (e.g. a bright blue is RGB(0,0,255); if it's present for land and the latitude shader fails to fire, then the result will be RGB(0,0,255)*0.5+RGB(0,0,0)*0.5=RGB(0,0,127), or a dark blue. The system needs some better logic for handling colors. It just takes some programming time.


Exactly that appears clearly in the example of the code you showed.
However when even I could see the cause of the problem (I never programmed anything serious) and how to heal it by basically replacing the linear blend by 2 lines giving realistic results  then it shouldn't take more time than a few hours. 
Of course to that adds the time to change the blend tab in order to add * one*  parameter that I introduced - the biomlimit and here I don't know how long it takes to program a change of a tab.
This change would cover in my estimate 90% of a user's needs because when you get altitude and latitude colors right, you get right all you need for a world's creation. The slope and orientation colors are only anecdotic and could be removed altgether because considering such details makes only sense on much smaller scales (subcontinental) and even then for only exceptionnal needs.
Basically the right logics is just avoiding color mixing because its results are unpredictable and this mixing is avoided by just adding limit parameters which serve to cut the space in regions where always only a single shader applies.
Optionnally the boundaries could be blended but here I am already in the fine details.

In the experiments I did, this module of Wilbur shader looked totally independent from everything else so that changing 2 lines shouldn't interfer with the core of the software so there should be no additional interfacing work involved.
Of course it would be nice if that was fixed because then Wilbur could be used almost from the beginning to the end of a world creation process, sparing time to learn another software for the realistic coloring.
But if that was not a target and you don't intend to spend any time with Wilbur anymore then who are we to ask you to change something ? 

We live in your world as Everquest designers aptly said one day  :Smile:

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## Deadshade

Now I am struggling with the rivers.
I followed step by step "Fun with Wilbur volume 1" because this is approximately the look I wanted.
It failed.
The incision function didn't do what is shown with the document.
The canyons were less deep and less fractalised.
As this function takes an unholy time despite my rather top end CPU and the preview button didn't seem to do anything, I couldn't experiment with the settings.
I think I have an idea what the settings should qualitatively do (with the exception of the pre, post blurs) but not quantitatively.

I suspect that the result depends on the size of the map (My master map is 5 000x10 000) and yours in the tutorial was probably smaller.
Could you recommend some better setting and the number of incises one shoud do and how the map size impacts these settings ?

Another problem was with the river flow which may be related to the previous one.
When the slider goes to "long rivers" I don't get long rivers but many more short rivers.
When the slider goes to "short rivers" I get much less rivers of all sizes. So the slider rather seemed to do "many rivers" or "few rivers" instead of long and short.

The worst being that among the hudreds of rivers I got, almost none went to the sea. All were extremely short and stopped in the middle of nowhere. Some were cut in several non continuous segments. About any bump on the map even a few 100s m high seemed to generate a river.
Could you explain this problem ?

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## Deadshade

Well having given up on rivers in WIlbur I headed to FT3.
So I got now a semi reasonable map :



FT3 does rivers not so badly and especially it's very fast. There is the small problem that it creates rivers even by temperatures of - 10 but I can GIMP them away.
I am quite happy with the continental shelves . I even created large oceanic features by using low lacunarity fractals in Wilbur but the FT3 shader is too shallow and doesn't show them well. 
I would still like to edit the shader especially for the mountains and the deep sea but FT3 apparently doesn't allow shader editing.
Also it seems that rescaling (button remap altitudes ?) doesn't work. I select the continents, specify the max and min and the profile but what I obtain is much higher than the bounds.
Most problems seem relatively details now but one huge that has been plaguing me on different occasions since the beginning remains.

I have again this huge ridge in the sea going from - 500 to - 2500 (remainder of the shelf creation) which looks like a fist in an eye and I can't get rid of it.
I wanted to use rescaling on a selection but see above. Perhaps it can't be solved in FT3 andI'll  have to go back to Wilbur.

Can you advise how I can make a smooth transition from the shelf to the intermediary depths around - 2 500  so that this sea cliff doesn't appear anymore but the structure of the shelves is untouched ?

EDIT :
As the input from Wilbur to FT3 was 5 000 x 10 000, I wanted to save in the same resolution. But it seems that there is some limit to the size FT3 would save and help is no help.
Do you know if there is a limit and if yes how big is it for png and bmp formats ?

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## waldronate

The Fill Basins step is important because it enforces a unique flow path across the surface. Without that step, your rivers from Incise Flow become small and fragmented, because the flow channels are themselves small and fragmented. The white noise addition to the surface before the Fill Basins step is also important because it causes the rivers to wind in a pleasing manner instead of just flowing in fairly straight lines. Map Size has a HUGE impact on the perceived final result. The algorithm for finding flow is O(n*n*n), so it's extremely sensitive to surface size. Note that the precipiton-like algorithm that Wilbur implements doesn't guarantee continuous flow patterns, unlike the basin fill operation.

Pretty much everything that you're describing here is due to having discontinuous flow channels. There's no good way that I know to get that without the basin fill step, which has its own artifacts (no lakes, for example). If I get back to working on things, I'd like to allow the option to use the selection as a stopping point for the precipiton operation (it would also be nice to allow the selection to dictate where rivers could be found).

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## waldronate

It's certainly possible that the retail 32-bit version of FT has limits on the export. I don't recall. I just checked my internal build on Windows 7 64-bit and it seemed to generate a 10 000 wide by 5 000 high image without problem (it was slow, but you'd expect that).

The remap altitudes feature is a Wilbur feature that crept into FT; as such, it may not be obeying all of the assumptions of FT. 

As far as the step at the edge of the continental shelves go, did you try selecting an appropriate altitude range and blurring the result? Alternatively, select all land (altitude > 0), select>>modify>>expand the selection a bit to encompass the shelf area, then select all land again with a "subtract from selection" followed by a blur.

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## Deadshade

> It's certainly possible that the retail 32-bit version of FT has limits on the export. I don't recall. I just checked my internal build on Windows 7 64-bit and it seemed to generate a 10 000 wide by 5 000 high image without problem (it was slow, but you'd expect that).
> 
> As far as the step at the edge of the continental shelves go, did you try selecting an appropriate altitude range and blurring the result? Alternatively, select all land (altitude > 0), select>>modify>>expand the selection a bit to encompass the shelf area, then select all land again with a "subtract from selection" followed by a blur.


I have also W7 64. When I try to save 10 000 x 5 000 it says "Error 8 creating file. More than 1 650 000 000 bytes are needed to create and write the 10 000 x 5 000 file requested."
I have much more than 2 GO RAM and disk space available. This is annoying.

Yes I did. For the sheer drop from some - 400 to - 3000, repeated blur even with sigma 3 does nothing (e.g the drop stays). Substract from selection does nothing. But this is something I already wrote several thread pages ago - substract from selection and add to selection doesn't seem to work. The result obtained by using these options is exactly the same as Replace selection.
Isn't there a way to simply force the height field to be replaced by a linear (or other monotonous continuous function) ramp between Height min and Height max ?
Something like an S curve (or  a half mound to get monotony) that connects on top to the max value of the selection and on the bottom to the min value ? 

Regarding the river creation. As I said I followed your tutorial "Fun with Wilbur volume 1".
So I of course did the fill basin - noise - fill basin routine.
However I was sure that something was going wrong already after the first incise - what I obtained didn't look *at all* like your pictures on page 4. There where you were getting nice well defined  deep and broad canyons, I was seeing practically no effect on my map. So I concluded that the settings you suggest at page 4 are probably dependent on the map size and mine being relatively big, these settings were inappropriate. 
But as I couldn't experiment with other settings (every incise took some 5 minutes), I simply continued your tutorial untill the end just to verify that the end result will indeed be very different from yours.

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## waldronate

The retail FT3 is limited by the basic 32-bit Windows subsystem to 2GB of total working space. You can set the /LARGEADDRESSAWARE flag (Google for what and how) on your FT executable to use 4GB on 64-bit Windows. The 32-bit version of FT3 that I'm using already has the /LARGEADDRESSAWARE flag set and I forget that sometimes.

For your dropoff problem, make sure that you're blurring the channel that's causing it. Your dropoff could be due to changes in the offset channel, prescale offset channel, or even roughness channel; blurring a channel without data in it will have no effect, regardless of how much you blur it.

Neither Wilbur nor FT have a feature of the sort that you describe. It should be possible to implement such a thing, but it would probably be a bit clumsy to operate. The previous tutorial about how to make a flat-topped mound is an example of a set of workarounds to get that sort of effect with the current implementation. You might also be able to use the profiled mound option with most of the second part being a flat section. Still clumsy to operate, though.

When you said that you were having problems with add to selection and subtract from selection a few pages back, I thought you were referring to Wilbur. I may have forgotten to hook up that setting for that particular feature in FT. It certainly wouldn't be the first time that I've made that sort of mistake.

If I recall correctly, there is a recursion limit on the basin filling code that causes it to stop processing at a certain depth (the recursion depth needed is a function of surface size and complexity). You're using a surface larger than about twice what I would normally use, so you may well have hit that limit. For very large surface, I tend to work at a much smaller resolution (1024 or less) and then scale up the data to the final form after I get the basic shapes and patterns that I'm looking for.

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## Deadshade

> The retail FT3 is limited by the basic 32-bit Windows subsystem to 2GB of total working space. You can set the /LARGEADDRESSAWARE flag (Google for what and how) on your FT executable to use 4GB on 64-bit Windows. The 32-bit version of FT3 that I'm using already has the /LARGEADDRESSAWARE flag set and I forget that sometimes.


OK will try to Google it. Normally I avoid touching at things internal to the computer because I am really ignorant in those things.




> For your dropoff problem, make sure that you're blurring the channel that's causing it. Your dropoff could be due to changes in the offset channel, prescale offset channel, or even roughness channel; blurring a channel without data in it will have no effect, regardless of how much you blur it.


First time I hear that word. What channel ? The drop off is simply caused  by operations that lowered the ocean while keeping the shallower seas around the continents at their right depth (0-500 m). I did so with an inverted mound and added a fractal with low lacunarity to have large scale deep ocean features. Corollary is a 2000 - 3000 m cliff between the edge of continental shelf and the deep seas. So its just due to the height field. See image :








> When you said that you were having problems with add to selection and subtract from selection a few pages back, I thought you were referring to Wilbur. I may have forgotten to hook up that setting for that particular feature in FT.


Yes I was referring to Wilbur. When I do a selection and then a second one then regardless if I use add or subtsract I obtain always the same result which is simply  replace. Either I am missing something obvious or it doesn't work.




> f I recall correctly, there is a recursion limit on the basin filling code that causes it to stop processing at a certain depth (the recursion depth needed is a function of surface size and complexity). You're using a surface larger than about twice what I would normally use, so you may well have hit that limit. For very large surface, I tend to work at a much smaller resolution (1024 or less) and then scale up the data to the final form after I get the basic shapes and patterns that I'm looking for.


Yes that must be the cause because what I observe (interrupted rivers, rivers ending in the middle of nowhere etc) looks like if the fil basin didn't do its work.
I never like to upscale because it looses accuracy. Always preferred the other way round - removing pixels that exist is not a problem but adding pixels that don't exist is.

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## waldronate

The steps to set the /LARGEADDRESSAWARE flag on the executable don't affect any other part of the system, just that executable. The wonderful thing about ignorance is that is 100% curable.

The Add and Subtract selection things are doing something, but not what they should be. I probably have the logic backwards for them in the code somewhere (it looks like it's doing the opposite operation on the logical NOT of the calculated selection). One more for the bug list, I suppose.  In FT, you should be able to use the lasso tool to select everything around the land, then use select>>altitude range with low=-1000000, high=0, and operation=Subtract From Selection to select just the ocean parts of a rough selection.

One advantage of working with a map showing a large area is that different maps will have different levels of detail available. An onscreen map, for example, is typically 2000 or less pixels wide. It's only for very large printable maps that you'd need to go much larger. The nice things about fractals is that higher-frequency details can be generated by adding more octaves of noise. In this case, if a river channel is enforced and the terrain generally processed at 1024 pixels wide, then scaling up to 2048 pixels, adding a little more noise, filling basins, and fluvial erosion of some sort (incise flow and/or precipiton) won't change the behavior of the rivers at the larger scale, merely add more detail. This process can be repeated a few times to get from the 1k to the 10k map with very little in the way of change to large-scale features. This processing flow allows for lots of work iterations at lower resolution (because it doesn't take long), while still giving acceptable results for the higher resolution results. http://www.cartographersguild.com/ma...-wilburia.html is an example of a map that started at 500x500 (I downsampled the original 2000x2000 masks for convenience of iteration rate) and then upscaled to 1000, 2000, 3000, and finally 6000 pixels wide. The whole generation of the terrain took about an hour or so because I was able to get what I roughly wanted at low resolution at a few seconds per iteration and the just add data using the processing loop described above (I settled on that loop, btw, because it is fairly stable and also gives reproducible results).

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## Deadshade

> The steps to set the /LARGEADDRESSAWARE flag on the executable don't affect any other part of the system, just that executable. The wonderful thing about ignorance is that is 100% curable.


Yes as a scientist I know something about that  :Smile:  
However in this particular case I remember how I was tuning the floppy rotation speed with a screwdriver many years ago and I can't say that this kind of activity (albeit more sophisticated in 2014) motivates me to cure my ignorance.




> In FT, you should be able to use the lasso tool to select everything around the land, then use select>>altitude range with low=-1000000, high=0, and operation=Subtract From Selection to select just the ocean parts of a rough selection.


Yes I could do that. But how does that solve the cliff problem ? Just selecting the sea in a band around the cliffs doesn't solve it. I already tried in FT3 deterrace which does nothing and remap altitudes which vaguely does something but not what I need. Beyond that there is no function that deals with geometry - almost everything is about adding or substracting what just generates cliffs.




> The nice things about fractals is that higher-frequency details can be generated by adding more octaves of noise. In this case, if a river channel is enforced and the terrain generally processed at 1024 pixels wide, then scaling up to 2048 pixels, adding a little more noise, filling basins, and fluvial erosion of some sort (incise flow and/or precipiton) won't change the behavior of the rivers at the larger scale, merely add more detail. .


Yes I realize that. Yesterday I did a map for a new guy here who was asking for help in the member introduction subforum. With what I learned, I could do it in about 1 hour because I went with a 1000x2000. Incise took 5 seconds and fractals were instantaneous. Of course I regretted for the Nth time that Wilbur had no fractal coast generator, no continuity generator and that the color management was bad but one can get interesting height fields with erosion details pretty fast. 
Incidentally it gave me the answer on my question about your tutorial "Fun with Wilbur Volume 1". Yes my problems were due to the size of the map. When I did it yesterday for the guy's map on the much smaller 1000x2000, I got the same results that you show in the tutorial.
I didn't use this scaling technique for my map because as I was juggling with a half a dozen softwares trying to figure out which was doing what, I ran immediately in the problem that among the crowd of maps in different resolutions I lost track which was what. So I focused on a master format 10 000 x 5 000 everywhere but in FT3 which doesn't allow it.

Btw a specific question about the map you linked.

Your mountains there don't look at all like things that Wilbur generates randomly. You did them with contour masks and then filled in fractals with high radius ? Or some other method ?

And while I am at it, another question. I noticed that both WIlbur and FT generate almost always non realistically looking land at the upper and/or lower edge of the map. Are there some artefacts wreaking havoc with the fractal at the poles ?

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## waldronate

Blur is a low-pass filter that will smooth out that transition. The wider you make your blur kernel, the more of the surface it will use in its operation. To reduce a cliff in an area, the basic technique is to select the problem area, feather the selection a bit so that it eases the transition into neighboring area, and then apply a large-radius blur through that selection. The blur will compute an average of the surface over its area of effect, and then apply that average to the surface. You go from having a hard-edged dropoff to a smooth one.

The start of the Wilburia topic shows the two masks used for the terrain, one for coasts and one for mountains. A third mask can be applied to get specific peaks, a fourth can be added to get subsea topography, and so on.




> I noticed that both WIlbur and FT generate almost always non realistically looking land at the upper and/or lower edge of the map. Are there some artefacts wreaking havoc with the fractal at the poles ?


I don't understand this statement. If you mean that the fractal noise appears to be stretched horizontally by a 1/cos(latitude) function, then that is what happens when you sample a spherical noise surface and project it to a plane using the equirectangular projection. If you view those worlds in the Orthographic projection, you'll see that the fractal parts are as undistorted as in the equatorial regions. If use a planar fractal and then project it to a sphere, you'll see unsightly pinching at the poles.

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## Deadshade

> Blur is a low-pass filter that will smooth out that transition. The wider you make your blur kernel, the more of the surface it will use in its operation. To reduce a cliff in an area, the basic technique is to select the problem area, feather the selection a bit so that it eases the transition into neighboring area, and then apply a large-radius blur through that selection. The blur will compute an average of the surface over its area of effect, and then apply that average to the surface. You go from having a hard-edged dropoff to a smooth one.


There has been a misunderstanding. As you were talking about FT, I looked for a blur in FT and didn't find any. So I assume you were either meaning going back to WIlbur and blurring there (I already tried that a few days ago with little result) or the blur is well hidden in FT. OK going back to Wilbur and retrying.






> I don't understand this statement. If you mean that the fractal noise appears to be stretched horizontally by a 1/cos(latitude) function, then that is what happens when you sample a spherical noise surface and project it to a plane using the equirectangular projection. If you view those worlds in the Orthographic projection, you'll see that the fractal parts are as undistorted as in the equatorial regions. If use a planar fractal and then project it to a sphere, you'll see unsightly pinching at the poles.


Yes I noticed the 1/cos. But I was meaning that there seems always to be land in high latitude and on poles and never sea. When I run 30 fractals I'd expect roughly 1/2 with land on poles. But it is much more - I'd guess 8/10.
So I wondered if there was some bias.

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## waldronate

In FT, it's Tools>>Global Smooth.

It should be fairly randomly distributed. It does seem to occur in clusters, though. Moving the world center slightly one way or another is a way to fix this problem.

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## Deadshade

> In FT, it's Tools>>Global Smooth.
> 
> .


Ah yes this one I tried first on the selection because I imagined that it would be something like blur. But as it had no effect I forgot it. As I didn't know what amount to set, it may be that I used a too small one.

EDIT : I confirm. I just did in FT 4 global smooths with amount 100 on the selection and nothing happened. The cliffs are still there. This is crazy.

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## waldronate

Try Tools>>Global Smooth>>Land Offset with an amount 2 instead of an amount 100 and see if that does anything. I've never tried an amount of 100 and don't know if it works correctly.

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## Deadshade

> Try Tools>>Global Smooth>>Land Offset with an amount 2 instead of an amount 100 and see if that does anything. .


No it doesn't. In FT applied 10 times global smooth with amount 2 on the part selected between -4000 and -300 (the cliff happens approximately around -500 falling to - 3 000).  It didn't blurr the smallest bit and the cliff is still there. Perhaps it doesn't work Under the sea - I can't think of anything else.
Will try to do something with mounds in Wilbur but if I can't find something, I'll simply GIMP it away. I know this is brutish but I hate discontinuities.

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## waldronate

I'm not sure what's going on. Unless, of course, you're using a binary input file and not using Burn Into Surface, of course. In that case, nothing will have any effect on your surface because binary data can't be edited in FT (FT can only edit data that's stored in one of the editing channels).

I whipped up a quick world with the same basic characteristics in FT, including that cliff.


I selected everything below -1000, did a border on that selection, feathered the selection and finally did a global smooth on it:


EDIT: looking again at your previous image, I see that there isn't any overshoot on the cliff, making it likely that you're using the binary input data.

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## Deadshade

> I'm not sure what's going on. Unless, of course, you're using a binary input file and not using Burn Into Surface, of course. In that case, nothing will have any effect on your surface because binary data can't be edited in FT (FT can only edit data that's stored in one of the editing channels).
> 
> 
> 
> EDIT: looking again at your previous image, I see that there isn't any overshoot on the cliff, making it likely that you're using the binary input data.


Well yes. I imported the map from Wilbur . That goes only when starting with new->binary etc. So I guess it was (is ?) binary.
After that I edited it because I went to FT for the rivers so obviously the river creation worked (if this counts like "effect on the surface").
Then I saved the result in FT format (the map I joined above is the FT format).
And after that, in the multiple attempts, I always loaded the file saved in FT format.

So no, I didn't do Burn into surface at any step because as I understood the manual, it was only necessary if the original binary file (this would be the .mdr Wilbur file) was moved or deleted. It wasn't.

In the case I misunderstood the manual, I will test the smooth after having burned.

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## waldronate

A world created from binary data only uses the data from the binary file and it ignores the offset, prescale offset, and roughness channels. Saving an ftw file from a binary world just saves the name of the binary file in the ftw, not the data. Operations like raise, lower, smooth, and so on will have no effect on the binary data, just on the channels that are not being used. Operations that are based on information derived from altitudes (river finding, temperature computations, coloring, etc.) will use the binary data.

The Burn Into Surface operation samples the binary file into the offset channel at the resolution of the offset channel. The binary file is no longer used after the Burn Into Surface operation.

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## Deadshade

OK after having burn into surface I got 2 things.
- the smooth worked more or less. Not as well as in your example but there was an effect. It didn't cover the whole space between the selection boundaries like in your case - in some places it did in some other it didn't.
- It destroyed the hills, mountains and rivers. Mountains became these smooth worm like bumps. Basically it looked like if the height field lost most of its fractality and the hills are just hemispherical mounds.

So I guess it was from Charybda to Scylla.

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## waldronate

Burn In To Surface downsamples your surface to the currently-set editing resolution. If you don't change it, that means that you get the a 256-wide surface, which will look really ugly. The maximum allowed editing resolution in the 32-bit version of FT is 8190 samples wide (Map>>World Settings, Editing page).

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## Deadshade

> Burn In To Surface downsamples your surface to the currently-set editing resolution. If you don't change it, that means that you get the a 256-wide surface, which will look really ugly. The maximum allowed editing resolution in the 32-bit version of FT is 8190 samples wide (Map>>World Settings, Editing page).


I came back to the map after a longer break. YEs, I missed the resolution bit (it is not mentionned in the FT manual in the short comment about Burn into surface).
As I said, I don't get the same result as you did. The cliffs still more or less stay on some places.
Anyway I simply GIMPed it over so that the visual problem is solved even if the heigght field one isn't.

A small question about precipitation field in FT. How is it computed ? Just a random function with some latitude dependence ? Or did it use a partial pressure function at saturation ?

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## waldronate

> A small question about precipitation field in FT. How is it computed ? Just a random function with some latitude dependence ? Or did it use a partial pressure function at saturation ?


It uses a base value with a temperature (and thus altitude) dependendence as well as a random amount. See attached for the FT V1 manual section on the elements used. It leaves out the prescale offset things because they weren't in the system at that point.

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