I've been using Wilbur a lot for the past month or two. It's a really excellent little program, and I'm very happy with it.

During all these hours spent in Wilbur, I've come across a few things that I'd like to ask about. So here goes:

1) I'm using Wilbur to develop a world, continent by continent. But I've noticed problems when working with larger sections. My final goal resolution for the world map level is 0.5 km per pixel, which will leave me with a final map of 86,400 x 43,200 pixels. Obviously this is totally impractical for a single file, but it doesn't have to be if you split the world up into sections. Naturally, continents are the easiest section to work with, and even the largest is only a fraction of the full map. Even then, though, working with images of say for example 14,000 x 20,000, or even 11,000 by 11,000, I have found that I encounter problems - specifically, with Fill Basins. It produces a strange effect where large portions of the map get filled in at an oblique angle.

The other problem I encountered was with Precipiton Erosion, on a very large map of 22,000 x 14,000. The erosion seemed to work properly on the left hand portion of the map, but more than half of the right side of the map either experienced less or no erosion.

This all leads me to wonder: I've had none of these problems since reducing my fragment sizes to less than 10,000 pixels square, so could there be some fundamental problems with working on these super size maps?

2) With the 3D viewer, I have been finding that 9,999 pixel square images are too much for it. It's an absolutely invaluable aid to working on a map, though, so I chose a 2,500 pixel square section of my map for testing, to develop an "erosion recipe" for use on larger sections. It works really well at this resolution. Again, is there an in-built limit for what the 3D engine can display?

3) Another problem I've been trying to deal with is regularity of mountain heights - which is to say, all Wilbur's mountains tend to end up at about the same height. This is especially causing me problems since I have to go to Photoshop via PNG to stitch the maps together again, but of course PNGs automatically scale the map from lowest to highest across the greyscale spectrum. Do you have any advice for dealing with this issue?

I've found that using adjustment layers with clouds set to multiply in Photoshop allows easy randomisation of the peaks without causing problems with river systems. But that only helps within each section.

I don't want to swamp you all at once, so that's all for now.