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[n00b] how would you do this shoreline? - Printable Version

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[n00b] how would you do this shoreline? - jhoo - 09-11-2018

getting back into mapmaking, using an app called HexKit. normally it's a nice speedy way to bang a map together because the tiles come pre-made and you're spared a bunch of techy details.

that said i've found that i want/need to make some tiles of my own for a bit of geography specific to my own world.
that has me wondering how i would do shorelines in GIMP.

here's an example from an excellent tile pack called HexMarch:

[Image: attachment.php?attachmentid=110050&d=1536597366]

if you zoom in on that you can see the way he's done shorelines:

[Image: attachment.php?attachmentid=110051&d=1536597594&thumb=1]

i've got water tiles to use as background, and the land areas that i have cut my basic coastline from but it's that transition area that i'm really wondering about, that land-to-water area that i think looks quite good.

so, GIMP n00b that i am, i'm wondering "how do i do that?"


RE: [n00b] how would you do this shoreline? - rich2005 - 09-11-2018

Not easy when these tiles are small, you might get something like this: Using Gimp 2.8

[attachment=2078]

1. A grown selection based on the land area. A little distortion to the selection Select -> Distort (very small values) Then a new white layer filled with gray.

2. Using layer, Filters -> Edge Detect -> Neon again with small values.

3. That layer eroded Filters -> Generic -> Erode

4. Colored blue Colours -> Colorify and the layer in Screen Mode.

The land border is just a selection stroked. No fade out along the coast line, that would be a another layer and a layer mask (probably).

Almost certainly not the way it was done. possibly from https://www.cartographersguild.com/showthread.php?t=1142 

I really advise you to look at this for general ideas, concepts and procedures. It is long and not easy going.

There is even a script devolved from that but learn how to get there using standard tools first. Not much learned using a script like this:  https://www.gimplearn.net/viewtopic.php/Render-Map-Script-for-GIMP?t=769


RE: [n00b] how would you do this shoreline? - mholder - 09-11-2018

Personally, I would do everything with blend masks and paint the waves/shorelines with the new smudge tool.
[attachment=2080]
This is a slightly different style, I admit, but I suppose any texture pattern could be used.

The key concepts are using masks for land, and then using inverted masks for water.

To make it blend better, blur the masks, and to grow or shrink them use the filters Filter->Generic->Dilate or Erode.

Since I made this in 2.10, and I don't know what version you are using, here is a .psd example that 2.8 can open, I believe.
[attachment=2079]


RE: [n00b] how would you do this shoreline? - jhoo - 09-11-2018

excellent info guys! gives me good stuff to mess with and learn. thanks very much.

@mholder : file opened nicely in 2.8.xx, tyvm.


RE: [n00b] how would you do this shoreline? - mholder - 09-11-2018

With that picture update, I still suggest using masks and blurring, dilating/eroding.
[attachment=2082]
And for example:
[attachment=2083]
And I wouldn't use a neon glow or anything like that, but rather I would duplicate the water texture layer and run a Colors->Hue,Saturation,Lightness adjustment, and then make it brighter.

This is a super fast example that could be better, but still the concepts are the same.  I recommend looking at each layer turned on and off to see how I did this.  And this isn't of course the only way to do it.

--edit
Sorry about that, but 2.8 doesn't have layer group masks, so that file may not work on 2.8


RE: [n00b] how would you do this shoreline? - jhoo - 09-12-2018

(09-11-2018, 06:34 PM)mholder Wrote: ...
--edit
Sorry about that, but 2.8 doesn't have layer group masks, so that file may not work on 2.8

no worries, i've stepped up to 2.10. and many thanks for the update, looking good!