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

[Aidan]

Okay, I got past that problem. I was using a lower blur on my landmasses, because I had a fairly detailed coastline. The noise layer was just having a very small effect. I'm probably using this technique on a scale it's not meant for.

I'm pretty pleased with the results so far, but have bogged down at the rivers stage now. When I draw lines in black on the grass mask, it makes the rivers almost white, the lightest water color, which is the color from the layer that I used for the shorelines.

I'd attach my xcf file, but even zipped it's over 7 meg. Here's a jpg of the results though.

[Karro]

Okay, I got past that problem. I was using a lower blur on my landmasses, because I had a fairly detailed coastline. The noise layer was just having a very small effect. I'm probably using this technique on a scale it's not meant for.

I'm pretty pleased with the results so far, but have bogged down at the rivers stage now. When I draw lines in black on the grass mask, it makes the rivers almost white, the lightest water color, which is the color from the layer that I used for the shorelines.

I'd attach my xcf file, but even zipped it's over 7 meg. Here's a jpg of the results though.

I had the same problem (with regards to the continent outline). There's a certain level of detail for which this technique will not produce satisfactoricaly fractalized-looking coasts. You have to be willing to sacrifice a lot to the blur to make it work.

With regards to the river, if I recall the way the tut works, you're basically masking out part of the land to expose the underlying water color, But since the color that lies directly below the continents is the almost-white shoreline color, your rivers will look almsot-white, too.

If I'm recalling correctly then here's one potential solution: with your land showing, and your rivers already masked out, add a new layer between your lowest land and your topmost ocean layer. On this new layer (call it river color, or something) with a thin soft brush set on an intermediate blue value paint along the lines of the rivers. Play with different brushes and different layer settings to get the blend with the shoreline blue-white layer looking right. (I suggest leaving both your land layers and ocean layers showing so you can see the effect of the work as you paint.)

[Aidan]

I had the same problem (with regards to the continent outline). There's a certain level of detail for which this technique will not produce satisfactoricaly fractalized-looking coasts. You have to be willing to sacrifice a lot to the blur to make it work.

With regards to the river, if I recall the way the tut works, you're basically masking out part of the land to expose the underlying water color, But since the color that lies directly below the continents is the almost-white shoreline color, your rivers will look almsot-white, too.

If I'm recalling correctly then here's one potential solution: with your land showing, and your rivers already masked out, add a new layer between your lowest land and your topmost ocean layer. On this new layer (call it river color, or something) with a thin soft brush set on an intermediate blue value paint along the lines of the rivers. Play with different brushes and different layer settings to get the blend with the shoreline blue-white layer looking right. (I suggest leaving both your land layers and ocean layers showing so you can see the effect of the work as you paint.)

Yeah, I think I did something similar to what you're suggesting. I simply made another layer between the shoreline and the grass layer and used some cloudy noise and a color gradient with a couple medium blue colors then masked it with the land mask, and voila, there's blue beneath it.

I used RobA's tapered path stroking script and got a nice river, now I'm trying to figure out how to use a bump map to make it look even better.

[Karro]

Yeah, I think I did something similar to what you're suggesting. I simply made another layer between the shoreline and the grass layer and used some cloudy noise and a color gradient with a couple medium blue colors then masked it with the land mask, and voila, there's blue beneath it.

I used RobA's tapered path stroking script and got a nice river, now I'm trying to figure out how to use a bump map to make it look even better.

To do this, what I've done is this (and YMMV):

I included my rivers on my land mask, so that the land mask shows both the outline of the land as well as the rivers. I took this and made a new layer out of it - that is I created a layer where everything that is water (including rivers and lakes) is black and everything that is land is white. I blurred this slightly (how much will depend on the size of your map) but between 2 and 10 pixels ought to be enough. Then, I created a new layer filled with 50% gray. On this layer, I rendered a bump-map with my black-and-white land/water layer as the source. I don't remember the exact settings, but fiddle with them until you get something decent in preview: it'll look like the rivers and the coast slope gradually into the water. Once you do that, set the gray bumpmap layer to Overlay, and voila!