Requesting tutorial for rivers

[Hoel]

The easiest way I can think of is hand drawing them with a tablet. It's fast, and with a bit of practice, easy. Plus you get good control of where they start and finish.
I might be a bit biased towards hand drawing, but i think almost everything looks better when you do it by hand, coastlines, rivers, lakes, height and so on. It's all about controlling the map.
Generating coastlines can be good sometimes, aspecially when you can adapt the actual use of the map to the map itself. If i make a map before writing a campaign about it, it doesn't matter.

[Nomadic]

The easiest way I can think of is hand drawing them with a tablet. It's fast, and with a bit of practice, easy. Plus you get good control of where they start and finish.
I might be a bit biased towards hand drawing, but i think almost everything looks better when you do it by hand, coastlines, rivers, lakes, height and so on. It's all about controlling the map.
Generating coastlines can be good sometimes, aspecially when you can adapt the actual use of the map to the map itself. If i make a map before writing a campaign about it, it doesn't matter.

I agree. I have found that with the technique I use for random generation, it still turns out better if I take bits and pieces and move them around to my liking. The human mind still outperforms any PC fractal program.

If you really want help with random rivers then there are two things that I sometimes use that might help. The first one is the quick way when I just need a river fast. For that you do a cloud noise filter (plus difference clouds if you're using photoshop) then use layers or thresholds to get everything white except for the thin twisty black lines. After that you just slice out sections and plop them down wherever looks good and then fill and bevel it so it looks river like.

The other way is a bit longer but it is easy and looks good. For that you will want to make a height map for your continent (there are plenty of tutorials around here that talk about how to do that). Then once you have got it to your liking you plop it down and trace the contours of the rivers based on the slope of the land. I find that if you do a mid blue (a bit lighter than the ocean) and stroke it with a slightly lighter blue it gives you a nice look. After that you blur it just a little (enough to merge the stroke with the river lines) and viola.

[Redrobes]

Getting rivers in approximately the right place is fairly easy. To do it automatically with a PC is pretty hard.

Firstly - take a look through this little tut. I wrote this but its actually a collection of ideas and stuff we have talked about on these boards for a while by many people.

http://www.cartographersguild.com/showthread.php?t=3822

I write an app which calculates rivers automatically which is the GeoTerSys link in my sig - theres some movies on there to show what its doing. But the app is one of several trying to solve this very hard problem. Its a LOT harder than it first appears. Obviously water flows downhill and we can program that easily but that's not the end of the issue. It gets complicated from there and thats where the real fight is taking place.

Waldronate (joe) on these boards writes Wilbur which is what Jezelf (also on these boards) was using to get his rivers out of his terrain. If you look in my sig again there is a keyword index. Look up Wilbur in there and Joe has done a few tutorials for it and shows how to do the rivers using it.

Apps like Wilbur, mine, some of the GIS apps and the odd one or two more are the only options in this area right now and since Wilbur is kindly downloadable for free then I would suggest that would be a good starting point.

[Korash]

there is also this little tut

http://www.cartographersguild.com/showthread.php?t=2711