Hi Construc, it's a lot of work. Yopu could use layouts set out on 3 levels. Large, med, small. Use channelling erosion to cut additional valleys. I did create the Misty Mts using just layouts. The number of splines I used was silly...depending on what resolution you are working at, the numbers can get very large. What's needed is either a layout tool which can procedurally generate ridge networks, or a new type of erosion that can cut the river networks- coming at the problem from different sides. I opted to use real world data in the end. That's fixed res of course, but you could apply certain methods to increase the resolution and networks. I think Wilbur might be a promising app to do this but it's limited in filesize to run 16K px.
Seeing as The Deselation os Smaug has released this: http://middle-earth.thehobbit.com/map , i thought it would be cool to try and re-create it, as i understand it a member here is doing just that. but what i wanted to focus on was the mountains, and how to re-create the segmented ridges?
purely on the level of techniques, what would be the best aproach for something like that? is it in the terraceing before erosion, or geological time enhancement?
Would i start with a large perlin ridges, link it in to a high flow, low intensity erosion, and use the flow output from that to mask a second erosion with high sediment carry to get the rivers?
i like to think im pretty proficient with WM, but a few pointers in terms of techniques and effects would help a lot :D