We are developing an indie story driven adventure game and our writer is writing specific geography into her story. Is there any information on how to create height maps for specific geography? I have googled and there is nothing specific I can find on controlling the painting to create a very specific geography. I have taken the common sense approach of black being nothing and pure white being the tallest points however our results have been negligible thus far.
A good introduction tutorial on procedural terrain can be found at the Red Blob Games blog.
You will also find that at some point, height maps will not cut it any more. There will be no overhangs, no caves, no bridges or tunnels possible with a height map.
But depending on your needs, you could stick with a height map.
From the same author, there is also this map generator, which is not a height map, but can help you get some ideas for controlling terrain features like rivers and such.