A windy river, a town, a keep... A GIMP project.

[arsheesh]

Hey there Surfarcher, I saw your other inquiry regarding Town mapping with GIMP and it caught my attention. I am a fellow GIMP user who is also attempting to flesh out a campaign setting. I am about to begin a new campaign and would like to create a map for the town that will serve as home base for the campaign. As such, I'm eager to see what other GIMP users have discovered in terms of the "How Toos" of Town/City mapping. Just curious how your own project is coming along and if you have made any progress since your last update.

Cheers,
-Arsheesh

[surfarcher]

Thats a very nice looking river. The banks might be a bit too "regular" but thats just my opinion.

I thought they were too regular too and fiddled with them some more. Last post updated. If you have any thoughts on additional tweaks to the banks I'd love to heard them.

Hey there Surfarcher, I saw your other inquiry regarding Town mapping with GIMP and it caught my attention. I am a fellow GIMP user who is also attempting to flesh out a campaign setting. I am about to begin a new campaign and would like to create a map for the town that will serve as home base for the campaign. As such, I'm eager to see what other GIMP users have discovered in terms of the "How Toos" of Town/City mapping. Just curious how your own project is coming along and if you have made any progress since your last update.

Hi Arsheesh!

I had to break off for a while because I had encounters to build and a 3000 x 2000 cave system to map out, populate and do encounters for. Game night is past and I have enough material for most of next session so I'll indulge in this some more

In case they are of any use to anyone I'll post my notes on the work so far in a moment.

[surfarcher]

Part 1 - River Curves

For me the fundamental and defining structural element for this map is the river, so I put a chunk of time up front into getting various aspects of the river right.

1. Make a new image of the desired size (3200 x 2400 for me) with a White layer.

2. We need some extra space to work with the curve or it will look wrong where the ends meet the edge of the canvas. Adjust your zoom so you can see the space well off canvas.

3. Use the paths tool and dialogue to define a new path. Make sure the very ends of the path are well off the canvas, well outside the layer. This lets us get a nice smooth curve without flat spots running through the border of the river.

Plonk down about four anchors, grab the line between each pair of anchors and give it a good bend to show up the associated handles.

4. Go into the Paths dialogue (normally between the Layers and Undo History and rename your new path "River Path". You'll find you come back to this area more times than you'd think to pick your path back up and adjust it.

5. Tinker with your "River Path" to get a nice river curve. Play around with the handles and anchors to adjust each curve section. Dragging the handles pretty far from the anchors helps get nice flowing curves in the long sections. Tight curves are a little trickier and require shorter handles.

Flat spots are the enemy here! It's worth spending extra time making sure every curve section feeds nicely out of the previous one and into the next one. Also, less anchor points are definitely of more value. Make this a game - try to get your perfect curve with the fewest possible number of anchors. Do this and you'll end up with better, smoother curves. I made five anchors to get this curve.

6. Once you think you have the curve right stroke it with the desired width of your river. Edit->Stroke Path... I stroked a 250px solid colour along the path.

7. This is where the flat spots really show up! You'll see "pinching" of your dirty think line where you have a flat spot. Simply undo the stroke, adjust the anchors and handles some more. Normally you want to slide the anchors away from the pinched area and then try to get the curve back with the handles. When you think it's right go back to 6. This normally takes a few attempts to get right.

8. Fuzzy Select your stroked area, invert the selection and make a new River Channel from it.



Part 2 - Building Up The Basic River

For the next few layers I used some variations of the techniques I picked up in RobA's excellent "Using GIMP to Create an Artistic Regional RPG Map" tutorials. Make sure you rep RobA on there folks and kudos RobA! The stuff I used in this part is derived from "Post 6: Create the Sea".

Here's what I did, as I remember it...

1. Deselect all, invert colours and apply a 250px Gaussian Blur.

2. Create a new layer called River and fill it with clouds (Filters->Render->Clouds->Solid Noise, size 3, detail 15, random).

3. Set layer mode to Overlay and merge down.

4. Add River Channel as an layer mask and apply the mask.

5. Auto-Normalise the layer yo9u just masked (Colours->Auto->Normalise).

6. Wand select non-transparent, alpha to selection and invert selection. White fill, select none and Gaussian Blur 20.

7. Gradient Map the palette to sea colours (set FG colour to dark water and BG to lightest water and Colours->Map->Gradient Map).

I use a number of layers to build up the effect at the edge of the river and the first of these was RobA's Seashore method to get a wispy edge. Go ahead and apply that. And yes you'll have to create a noise layer with all settings at max to do that



Part 3 - Painting the River

Well it's not too bad so far but. Um... It looks more oceany than rivery. A river at this elevation has a lot more detail. Rivers aren't very transparent and they tend to be a bit muddy. They also have debris and banks. Let's start towards adding that.

1. Create a transparent River Mud layer between the River and Seashore layers. Fill it with a tan colour (I used a78f6b) and set it's transparency to 20%

2. Copy River, bring it to the top and rename it Grass. Mask off the river. Edit the layer and Gradient Map the colours to some grass tones.

3. Create a Grass Texture layer, noise fill it and set it to overlay. Mask off the river.

We are getting towards what folks would recognise as a river! To my eye there are two things we need to do at this point. Add depth and add dirt.

4. Add a Texture Bump Map layer and fill it with turbulent noise, high detail, large size. Hide the layer.

5. Create a Texture Bumps layer, set it's mode to overlay, fill it with 50% grey and Bump Map it with the Texture Bump Map layer (Map Type: Sinusoidal, Depth: 4). You can mask off the river if you like but I liked it better unmasked.

6. Add a new layer called Dirt, fill it with a dirt colour, add some HSV Noise (tinker with Hue and Value until it's getting grainy) and bump map it off itself (depth is the key setting here).

7. We don't want this hard dirt in the river so channel to selection, choose the Dirt layer and hit delete.

8. Create a new white layer, channel to selection and fill the selection with black on the layer. Deselect all and apply a Gaussian Blur 100px.

The next few steps are almost directly out of section 10 in RobA's tutorial.

9. Create a new layer, noise fill (max detail, max size, turbulence off) and set the mode to Difference.

10. Merge down the difference layer and invert the colours on the layer.

11. Open the Colour Levels dialogue and tinker with the input levels.

Where there is white outside the river we will end up with dirt. We want more dirt next to the river and just a few patches elsewhere. If you don't quite get this right you'll need to do some touch-ups by hand in the step. The main thing is that you get enough dirt next to the river. Toning down the dirt away from the river is pretty easy.

Start by snugging your black and white markers down to either side of the peak you should have. Then tinker around with the grey marker (and the other two markers). You want some heavyish white adjacent to a lot of the river and some wispy white in other areas.

12. Select all, copy, hide the layer and go to the Dirt layer. Add a white Layer Mask to this layer, paste and hit anchor.

If this looks too overdone to you you can undo back to just before the levels and retry.

Now you may want to do some hand touch-ups. Grab a fuzzy brush, I'm personally fond of doing this with the airbrush. Where you paint white on the mask you'll get more dirt. Where you paint black you'll get more grass.

I wasn't imagining a particularly dirty region so I was fairly heavy handed removing dirt away form the river.

Finally a little Gaussian Blur (like 5px or 10px will serve to smooth any hard edges on the layer effect.



Part 4 - Bevelling the River Banks

It took a fair bit of tinkering to get the bevel "right" on the river banks. However after this we end up with something most folks will think is quite a nice river. A bit too regular and with no turbulence or debris. But quite nice nonetheless.

1. Create a new white layer call River Bevel. Channel to selection, grow the selection 20px and fill the select on the layer with black.

2. Deselect all and Gaussian Blur 200px.

Now if we emboss this we'll end up with something resembling a concrete half-pipe that will make any skaters amongst us drool. That isn't what a river's bevel's are like tho so we need to add some texture.

3. Add a new white layer. Channel to selection, grow selection 25px and feather selection 10. Now use Felimage (Filters->Noise->Felimage->Noise) to add some noise to the selection on the new layer. I used default settings here (size 10, lattice noise, Ofrdinary fBm).

4. Gaussian Blur 20px, set layer mode to Overlay and make a new layer from this (Layer->New From Visible). Rename this layer River Bank.

5. Now this should look somewhat like a river bank when we emboss it. Keeping your current feathered selection open the emboss filter (Filters->Distorts->Emboss). Choose Function: Emboss and experiment with the other settings until you get a result you find pleasing. You are after some nice texture and shading on the areas just outside the waterline. The middle of the river is irrelevant and dark patches at the edges will be dealt with shortly. I ended up with something like Azimuth 35, Elevation 45, Depth 33 but you'll get different results depending on your resolution, river shape, etc. Hit OK and wait for it to render.

6. Select none, channel to selection, grow selection 20, feather selection 15 and invert selection. Fill with 50% grey. Grab the fuzzy select tool (Antialising on, Sample Merge 3.5) and select the areas you just filled and fill with 50% grey again. Switch to Feathered Edges 10, Sample Merge 7 and repeat.

7. Select none, Gaussian Blur 20px, mask off the river with the channel and set layer mode to overlay. Turn off the other bevel work layers and you'll see your river banks!

At this point I went back and deleted the non-visible work layers. You can keep them (non-visible) if you prefer.


Coming up we'll need some turbulence and debris on the water and then the river itself will be finished.