[Award Winner] Using GIMP to Create an Artistic Regional RPG Map

[RobA]

Post 6: Create the sea. (in the beginning...)

To make the ocean/water (and the base contour for the land as well) a two layer variant of the three layer sandwich will be used.
Copy the “Land Mask” Layer, and rename it “Sea Shape”. Apply a Gaussian Blur (Filter->Blue->Gaussian Blur) large enough to eliminate the absolute black and whites of the image. In this case, I used the same size as the image (500px).


Create a new layer and call it “Sea Noise” Fill this with Clouds (Filters->Render->Clouds->Solid Noise) set to a low size (3) and detail of 15, reseeding the random number. Set the layer blend mode to mode to Overlay, then merge it down with the “Sea Shape” layer by right clicking on the layer and selecting “Merge Down”.


Duplicate this layer and rename it “Sea”. Add a layer mask by right clicking on the “Sea” layer, and selecting “Add Layer Mask”. When the dialog opens, select “Channel” (By default it should have the “Land Mask” channel shown and check “Invert”. Click Add.


Nothing much will appear to have happened, but there will be a mask next to the layer thumbnail:


Layer masks act like filters that let parts of the image “show though”. Areas where the mask is white will allow the layer to be visible. Areas where the mask is black will be transparent, and the various shades of grey will be varying degrees of transparency. Now right click on the “Sea” layer and select “Apply Layer Mask”. This will remove pieces of the layer based on what was showing through the layer mask. Here I have made all the other layers invisible to see the result:


Also, check out the histogram….that is where we start next.

[RobA]

Post 7: Create the sea, continued.

Now we want to stretch out the colours in the “Sea” layer across the entire black to white range. With the sea layer selected, auto normalize the image (Colors->Auto->Normalize). The histogram will now have little gaps in it. As the greys have all been spread out. To fix this, select the non-transparent area (by clicking on the “Sea” layer and selecting “Alpha to Selection”. Invert the selection (Select->Invert) and fill the area with white. Remove the selection (Select->None) and apply a 20px Gaussian blur.


Note the histogram is now filled in.

Now the next bit of magic. Set the foreground colour to the darkest water colour (water 5) by clicking on it in the Palette Editor (that we set up at the beginning), and set the background colour to the second lightest water color (water 5) by Ctrl-clicking on it.


Now we will turn the B/W into colour, by clicking Color->Map->Gradient Map, and the water is almost (for now).


Recently, I came up with a nice technique (in my opinion) to finish the shoreline water. Often people will stroke the shoreline with a light colour, or add a light blur. Here is a quick technique for making a unique look…

Create a new layer called “Seashore”, and fill it with the really light water colour (Water 1). Add a layer mask, using the “Land Mask” channel, and ensure “Invert” is unchecked.

(Any edits you do now will be on the mask shape, unless the layer thumbnail is clicked. The one you are editing will have a white box:


Give the layer mask a 10 px Gaussian blur.

Now apply a displacement map (Filters->Map->Displace). Use an X displacement of 20, and a Y displacement of -20. For both, pick the “Land Noise” layer. Set the Displacement Mode to Cartesian and the Edge Behavior to Smear.

Repeat this, flipping the signs, so set X to -20 and Y to 20. This screen grab is after the first one.


This will give a nice wispy, random looking water edge, once the land is put in place…

[RobA]

(And now for a commercial message...)


I'm pausing here. I'll try to get more up shortly...

Attached is a pdf (5MB) of the process up to this point.

-Rob A>

[RobA]

Post 8:Let there be Land.

Now that the ocean is completed, the land can be build up. Create a cop of the “Sea Shape” layer and name it “Grass”. Create a layer mask using the “Land Mask”channel. Click on the layer icon so we now edit the layer, not the mask.


Ctrl-Click on the dark green (Ditch) colour to make it the background and click on the light green (high ground) to make it the foreground colours, then Colour->Map->Gradient Map.


This is bland, so lets spice it up a bit…create a new layer called Grass Texture, and fill it with clouds noise (Filters->Render->Clouds->Solid Noise), detail 15, size 3, and new seed.
Again, add a layer mask using the “Land Mask” channel, and set the blend mode of the layer to overlay.


Looking better, but it could use some texture.
Create a new layer called “Grass Bump Map”. Fill it with rendered cloud noise again, this time setting the size and detail to the max, and selecting Turbulent.


Hide this new layer (by clicking off the eye icon). Create a new layer called “Grass Bumps” and fill it with 50% grey. Set its layer mode to overlay. It will appear to be gone now. That is how overlay works. 50% grey doesn’t change the underlying image, while darker shades darken the image and lighter shades lighten the image.
Now apply a bump map to this “Grass Bumps” layer using Filters->Map->Bump Map.


Lastly, apply the “Land Mask” channel as a layer mask like before.

[RobA]

Post 9:Finishing the Land.

After the bump map we now have this. You can adjust the opacity of the bump map to make it less noticeable if desired:


This is OK, but it is a little two green for me. One option is to change the overall colour by adjusting the hue, and that would be that. Instead, we’ll add a dirt layer. This will be a combination of a filter generated mask layer, and hand painting the mask.

Create a new layer called “Dirt” and fill it with the “med dirt” colour. Add some noise (Filters->Noise->HSV Noise):


Now bump map this layer on itself to give a bit of lighting texture:


Duplicate the “Land Mask” layer, bring it up to the top of the layer stack.


and blur it by 50px or so:

[RobA]

Post 10:Finishing the Land (cont.)

Create a new layer on top of the blurry one, and fill it with rendered clouds, maximum detail and maximum size, then set its layer mode to Difference. This gives a noisy blaxck outline of the coast. (This is also a nice technique to make a light water effect along shores…)


Merge down the difference layer, invert it, then bring up the layers dialog and adjust it to be a wider band of white on black. This will be used as the layer mask for the dirt….


Go back to the Dirt Layer and add a layer mask, using the “Land Mask” channel. Now right click on the layer mask and select “Apply layer”. This will erase everything that is not above the land.

Go back to the noisy blended layer you had created in the last stop (called land mask copy). Select all and copy this layer (ctrl+a, ctrl-c), Then select the “Dirt: layer, and add a layer mask and just select “White”. Now with the dirt layer mask active, paste the copy (ctrl-v). This will create a floating layer. Just hit the anchor icon to drop it down into the dirt layer mask. Now you can delete the temporary “land mask copy” layer:


This can be improved by applying a Gaussian blur (Filters->Blur->Gaussian Blur, 10 px) and some pixel spread (Filters->Noise->Spread 10 px) to the mask. I also took a soft white brush with 60% opacity and coloured in the areas I want to be desert. To make this easier, I moved my original sketch up to the top and set its blend mode to burn. This let me see where I needed to fill in deserts. Lastly, I reduced the opacity of the Dirt level down to get a nice looking blend.


Here is where we are so far:


Coming soon... Mountains.

[RobA]

Post 11:Let There be Mountains

Before you continue, there is a better way I found to make mountains located over here. It works well with the rest of this tutorial, and seems much easier and predictable than what follows here...


The technique for making the mountains is very similar to that of making the land. Because we have an idea for a map, we will start in this case by sketching a blurred representation of where they should be. Otherwise, just use one of the random techniques:

Create a new layer “Mountains”. Fill in white for the general areas of the mountain ranges, and apply a 50 px (or so) Gaussian blur. It is helpful to keep the original sketch on top with reduced opacity to act as a guide. Don’t worry about going in to the sea, because we can we can erase those areas later:


Now the noise layer (I used detail 8 and size of and set the blend mode to multiply. Then add a third layer (remember the TLS) as a clipping layer, and use the levels dialog to bring it down to show the mountains you want Here is the screen showing the three layers


Use the magic wand again to select the non-mountain area (like with the land) and create a new layer called “Mountains Mask” with a white on black. (Also the white colour selection as a new selection mask using Select->Save to Channel).

Now we want to create a heightfield from this. The easiest way I have found to do this is to copy the current visible image (Edit->Copy Visible) then paste it (CTRL-V) to a floating selection. Click the New Layer button to get it on its own layer rather than a floating layer. Now stretch the colour range out (Color->Auto->Normalize):


Rename this layer to “mountain colour”. Make a duplicate and call it “mountain bump map”. Now set the foreground colour to “lowest dirt” and the background colour to “highest dirt”, and on the “mountain colour” layer, do a Color->Map->Gradient Map.


Normalize the colours (Colors->Auto->Normalize) and add a layer mask, using the mountain mask channel. (Note, the Dirt layer was turned of in this image by accident).

[megabyter5]

I got to post nine before I realized everything was purple for some reason. Does this work with the newest version of GIMP?

[jfrazierjr]

I got to post nine before I realized everything was purple for some reason. Does this work with the newest version of GIMP?

Yep. There are a few things that might need to be cleared up, but it does you started. Save a copy as a .jpg file, start a new thread, and upload so we can check out your progress and help from there.

Joe

[RobA]

I got to post nine before I realized everything was purple for some reason. Does this work with the newest version of GIMP?

2.4 and up...

Like Joe said, post a sample (in a new thread, please....this one is getting way big) and we'll try and help you along.

-Rob A>