So I was looking through my HD yesterday, looking for stuff to trash prefatory to a little defragmenting of the HD. My laptop's been a little slow lately, seriously shortbus material. Anyway, I find a copy of the Vue 6 Infinite PLE. Well I can't really do much on it. With the time limit expired, I can't even render bigger than 320x240. But I decide to look at it's terrain editing. Wow! The editing is hugely superior to that of Bryce, and the erosion tools? Ohhh! Diffusion, Thermal(I haven't been able to see a difference between Diffusion and Thermal, but they work okay for plain vanilla 1998 soft erosion), Glaciation, Wind(kinda weak, actually), Dissolve(looks like precipiton from the ground up), Alluvium(the true killer app here... sexy...), and Fluvial(basically top-down Dissolve). Hoot mon, it's sweet!
I import my old noised, "Hi," terrain into Vue and start playing. Now the vue renerer seems to do well with tiny 256x256 terrains, which is good 'cause things get a little slow with larger terrains. So I downsample my original down to 512, which is a good tradeoff between speed and detail.
First off I use dissolve and fluvial at high hardness to start building channels to drain the many basins. I use a lot of alluvium to fill in the lakes from the other side. Most of my basins fill in and and break through pretty quick, but there are a few deep pits that hold out obdurately. No matter, I look for the lowest point on the periphery of each of those basins and use the Paint brush in Dig mode(small, soft, low flow) to give those an exit. I then use Fluvial and/or Dissolve to erode out channels, and then Alluvium, again to get the lake draining out. Tool marks are quickly obliterated by the canyons formed when the alluvium comes pouring out. It can be quite impressive to watch. A little bit more Dissolve, Fluvial, and Alluvium for good measure. I then use the x2 button at the top of the Terrain Editor to upsample the terrain to a more useful resolution. Before I export I run a little Alluvium to detail things. Don't use Dissolve or Fluvial at this point, they tend to make pits and it's slow as hell to fill pits at this resolution!
Now I hit the export button at the lower right side of the Terrain Editor. I select PNG as the object type go ahead and experiment with other types. When assigning a name for a PNG it's important to hit the browse button. The program crashes otherwise! Once you select a name, Vue asks you for Picture Format Options. I chose 65k Colors and High 100%. Hit OK and your back to Terrain Format Options. Now choose whether you want to generate material maps, and, if so, what format. Hit OK. This is the end of what I can do in the free version of Vue. Did I mention this was free?
Now to Bryce. Create a new terrain and open the Terrain Editor. Use the pictures tab to import your png. In retrospect, I'm not sure Bryce imports PNG as 16-bit. It might be better to open your png in Photoshop and, with the CartoPGM plugin, save to pgm, then use File>Import Object... to import the pgm into Bryce.
After getting my terrain into Bryce I open the Terrain Editor add a little Height Noise and a little Slope Noise then I Erode it a bit. Blur it slightly and use the grid control to upsample to 2048. Now I add a smidgen of Slope Noise(only) and a touch of erosion.
Next I found a nice material from my personal collection of saved materials and render at moderately decent quality. Have a look...