If you have ever tried making terrain for a computer game you'll know what I'm talking about. It simply isn't easy to make look good. And some types of terrain are easier than others.
Take my game snowballz for example. I found out that snow is very hard to make look good (or rather look at all). How do you texture snow so that you can see it but not look like cotton? And with shading; you have to darken everything in order to have highlights - but then it's, well, dark.
With the image on the left here shows a screenshot of snowballz and another game I'm playing around with making. It took me weeks (not working constantly on it; but still a long time) to get it to look the way it does... and it doesn't even look that great in my opinion.
But now on the right side is a tile/game engine I'm playing with (I don't know if I'll actually ever release it or not) and guess how long it took me to make it? About 3 hours for the terrain, 1 for the lighting, and 3 or 4 for everything else. I'll admit it doesn't look all that pretty either; but it took much less time to make than the snowballz terrain and I think it looks better.
I don't think my method of making terrain is half bad though. It's fast and looks half-way decent. You can check out 2Dland to see how I do it with vertex arrays. The implementation I use here is actually a bit different but still uses the same principals.
One day I'll figure out an uber awesome way to make two dimensional terrain... and you can be sure that I'll post here when I do :-)
