Creating Perfect Maps
I've tried a number of photostitching applications to create maps from game screenshots. The problem is that most applications are designed for photo panoramas, where a certain degree of inaccuracy is acceptable. For perfectly flat images like maps, this type of application fails. I've only found two applications that do an acceptable job of piecing maps together: nip2 and hugin.
Nip2 is my preferred application since it can easily handle large file sizes without a lot of memory, but is not very user friendly and can create some small black artifacts (which can easily be cloned out, so it's not a big deal). It is a graphical interface to a powerful programming language, so it isn't very intuitive as to how to use it. Plus, it gives cryptic error messages. Small price to pay for perfection, though.
Why Would I Want to Do This?
To achieve Grandmaster Cartographer in any given continent, it will be easiest if you compare your stitched together map with one that is confirmed to be 100% complete. We no longer host 100% maps because of bots and "browse offline" options that ate up all of our bandwidth.
Some people swear by the "zoomed out" method, but it only works in Tyria. You're better off going with a full-sized map and comparing yours to an overlay of a 100% version. Every spot counts for a tiny percentage, even if it doesn't look like it.
Can't I Just Layout the Images in Photoshop (or other application)?
Sure, but the images won't lineup properly. You'll find some images that match just fine, while others will be off by a half-pixel. You can probably still tell if you've missed a spot for the title, but it's annoying. This isn't a flaw in Photoshop: Guild Wars doesn't snap to the pixel for its maps.
Taking the Screenshots
The larger your screen resolution, the fewer screenshots you'll need to take. I use 1600x1200. For Guild Wars, you'll want to use the Mission Map ('u' map) and have it expanded to fill the entire screen. Take the screenshots in two steps: go to a southern outpost and take screenshots of all of the northern regions, then go to a northern outpost and take screenshots of the rest. That way you don't have your location marker in the image. Don't forget to trim off the UI elements that show up, you don't want those making their way into your map!
Try to get a healthy amount of overlap. I shoot for about 1" on all sides, more if there are no distinguisable marks along the edges of the screenshot. If you're going to piece the rows together first, try and make sure you drag the map as close to horizontally as you can. It's not important to be perfect, but it makes it easier to stitch them together.
Piecing Them Together
Nip2 is located in path_to_nip2/bin/nip2.exe.
For piecing together a mosaic (a multi-row panorama), you'll get the best results if you try to piece together all the rows or columns first, then piece those together. I prefer to stitch the rows together first, so from here out, when I say "rows", I mean "rows or columns". Nip2 gets cranky if your rows are not the same width when you go to piece them together as your final image, so you might have to take another set of screenshots for that row.
Open up your images. I name mine with this naming convention to make it easier to figure out which images to open: [row number]_[column number].[ext]. By default, nip2 will be set to only display native filetypes.
We'll start from left to right. Double-click on the first two images and find a distinguishable mark both files have in common. Sometimes it's just a subtle texture like these corner images. Portals between zones make the best "common" marker, except in snowy areas, where dark marks from trees or mountain peaks are the better choice. For this set of images, we have some really dark, distinguishable spots near those mountains. You'll want to place a marker as close to the same location in each image as you can. Don't stress over making it absolutely perfect, the stitcher will know where you mean.
You can close those images now. The main window now shows our markers just like it shows the images. Select both points and go to Toolkits > Tasks > Mosaic > One Point > Left to Right (if you press a key while hovering over this option, you can set a hotkey for it; mine is F9 now). That should give you a brand new image below the others (labeled as A10).
Open your new image along with the next image in the series (in our case, the 3rd image). Add the marks and join them together. Continue on adding marks to each newly joined image and the next one in the series.
Once you've joined all of the images together for that row, open the final one and save it. Nip2 can open this file again if you don't give it an extension, but nothing else can. So if you want to open it up in something else, give it an extension (JPEG or TIFF is ok, I use TIFF).
Tip: You might want to create a new "column" or "workspace" in nip2 for each row you do. It's not required, but it helps to keep things from getting cluttered.
Once you've got all of your rows finished and saved, open them up in a new column. This might take a while if the map is very large, like our Tyria map. From there, you just go on like you did before when you pieced together each row. Thanks to the wide images we have to work with, we're free to scroll to the best spot to piece them together, even the middle of the image.
Tip: Even though we're using "Left to Right" while piecing, the nip2 pieces them together the only direction they can fit together, including vertically.
If you get an ugly error at this stage, it usually means one of your rows is the wrong width. If you're stitching in rows, they should all be the same width. If you're stitching in columns, they should all be the same height. Sometimes restitching that row will correct the problem, but most likely, you'll need to take a new set of screenshots for that row.
©2006 Gamependium