Ley Lines

[DashBranaghan]

Hello all,

In my world, I have a collision/rift between planes called the Maelstrom, but I was also thinking that I could add Ley Lines as another overlay. The problem is, I'm not really clear on how to do this in Photoshop CS5. Has anyone introduced ley lines to their world maps, and if so, how did you go about doing it?

Any insight would be appreciated!

Cheers,
Rob

[Hai-Etlik]

In my world, I have a collision/rift between planes called the Maelstrom, but I was also thinking that I could add Ley Lines as another overlay. The problem is, I'm not really clear on how to do this in Photoshop CS5. Has anyone introduced ley lines to their world maps, and if so, how did you go about doing it?

Well, Ley lines are made up magic stuff, so they are whatever they are in your setting. That said, you probably want them to be "straight lines" which on a globe means great circles. In cylindrical projections, a great circle will generally look sort of like a single cycle of a sine wave centred on the equator (it will vary with the particular cylindrical projection). In a stereographic projection, they will appear as circles or straight lines (as will lesser circles so you have to know which circles are the right ones). In a gnomonic projection, great circles map exactly to and from straight lines. On the downside, Gnomonic can't cover a hemisphere, let alone a whole globe in a single map. If the map is in Normal Mercator, a simple sine wave centred on the equator is probably close enough for fantasy mapping purposes. You can adjust the amplitude from 0 to infinity, and the phase to anything you want (the frequency should always be once around the globe)

If you're making a large scale map of a smaller area in an extent appropriate projection, then great circular arcs will be close to straight lines regardless of which particular projection you use.

Here is an example of a Mercator map with a network of Great Circular arcs. ley.png created with this site: Mapping and Distance Tools