Looking in the Mirror

In which the Author turns a Critical Eye upon his owne Works

Most everybody -- myself included -- is sick of map borders at this point, and over on The Reddit one of the suggestions for a new topic was to post some maps and provide some self-review and criticism.  That's something I can do fairly easily over the summer while spending most of my time on other projects. 

 I fired up the generator and here is the first map that came out:

(Hopefully you can click through on the map to see it full size; if Blogger does something awful I apologize.)

I'm going to try to focus on areas where I think there's something interesting to say, but before I get into particulars, a few general observations.  I think there's a lot to like about this map.  It's well-composed and fairly pretty.  It's using one of my standard map styles, so the colors all work well together.  The subtle textures on both the land and the ocean keep the map from feeling too graphical.  The overall land shape is interesting, there's a nice variety of coastline from smooth to more fractal, and a good mix of islands.  None of the place names seem particularly stupid or artificial (although “Main" forest is borderline).  If I'm being honest -- and hey, why not? -- in my opinion this map is better than most maps you'll see on reddit/mapmaking and not in the bottom tier of the maps at Cartographer's Guild -- but also clearly not at the level of the better mapmakers at the Guild.  I'd say it's at the level of “talented amateur," perhaps.

Now for the problems and discussion...

While the overall land shape is interesting, and there's a nice mix of bays, points and islands, I'm not at all sure this is very “realistic" geographically.  At a regional scale almost any land shape is arguably realistic, and I don't think this map rings any strident alarm bells.  But at the same time, something like this at a larger scale would probably seem pretty artificial.  I haven't yet done a lot of work on continental scale maps, but this is definitely something that will need to be addressed at that scale.  Or I could just stick with regional maps :-)

Overall the label placement on the map is very good.  If you look at the labels you'll see that they're nicely spread out but still clearly attached to features.  There's one major labeling problem on the map -- “The Shellback's Croft."  This labels the unpopulated coastline along the southern part of that shoreline, but the label has been placed at an angle to, and crossing, that shoreline.  The reason for this is pretty clear -- it's not possible to place the label along that shoreline without crossing a coast -- either the coast of the large island at 2 o'clock or the shoreline coast.  It would have been better to place the label crossing the island, but Dragons Abound gets this wrong.  As I've noted before, labels are really hard.  I can make tweaks to fix this particular problem, but getting the right criteria to make labels always look perfect is very difficult.

Another label-related problem is the barrier islands on the lower right corner of the map.  The barrier islands are actually placed a bit off the visible area of the map, with the result that label for the islands ends up on the mainland and orphaned from the reference feature.  This happens because Dragons Abound doesn't display the actual edge of the map (where odd things can happen).  The solution to this problem is to not create barrier islands on the edge of the map; it turns out the code was sort-of trying not to do this, but not checking exhaustively.

One of the striking features of the map is the compass right in the center of the map.  I recently added the functionality to treat a map compass like a label.  During the label-placing process, the compass moves around trying to find a good placement.  In the case of a compass, this means in the middle of the ocean somewhere as far away from other features as possible.  In that respect, this code has worked perfectly -- the spot the compass has found in the center of the large central bay is the biggest area of open water on the map.  Of course, placing the compass dead center on the map is pretty unusual, and not really what I expected.  That said, I don't think it's a big problem, at least on this map.  If I really don't like this and it happens often, I can address it by adding a little heuristic for compasses that tries to push them away from the center of the map.

The final element of the map I'll comment upon are the mountains.  The random parameter selection here has resulted in mountains that are small relative to other icons on the map, and with very abrupt outline changes.  When the mountain icons are small, as they are on this map, it takes many of them to fill the mountain areas, and the result is more of a texture than a few representatives.  (There's something to be said about how the relative sizes of icons on a map affect our perception of the map, but I don't have my thoughts on that organized enough to write about.)  Instead I'll just say that I'm not overly thrilled with these mountains in either scale or shape.  Of course, it's easy enough to tweak the mountain generation parameters to stay away from this particular mountain style, but I have to be careful not to eliminate any creativity in the procedural generation.  (There's something to be said about the interaction between the size of the procedural generation space, the amount of creativity, and the amount of failure, but I don't have my thoughts on that organized enough to write about that, either.)  And something like mountains has lots of parameters, so it isn't always easy to know which parameter to tweak to avoid some unwanted generation.

Here's a version of the map addressing some of those problems:

It turns out that in the previous iteration of this map I had zoomed in to the central portion.  This shows a broader view.  You can compare this version to the previous version to see how the problems were addressed.

Another suggestion I received was to generate a number of maps using the full range of random generation and map styles to explore how well that works.  I don't have time to do a full exploration right now, but I re-generated the above map using a random style and the result was somewhat interesting:

If you compare this map to the previous one, you'll see that the land looks similar but not the same.  However, it is the same land mass -- the difference is that in this second map the sea level is lower, so there is more land showing.  The precise sea level is one of the random parameters in the full range of random generation.

Stylistically, the map is quite different from the previous one.  Most notably, the whole map (except for the edge scale) is in gray.  Forests have been drawn as individual trees rather than masses, and grassland is now empty, but deep grass is rather densely illustrated and given a shading.  There's now a coastal outline and an illustration in the ocean (but no compass).  The labels are all pretty reasonable and well-placed.  It's kind of interesting that on this map the proper names are quite long (“Dronshiduek," "Gupundumgill," “Blenshremmone") while on the previous version they were short (“Su," “Suglen," “Suam").  This is a feature of the name generator; it tries to create names within a similar family of names.

Overall I'd give the map another “talented amateur" rating.  There aren't any glaringly obvious problems.  The style is “okay."  It's not terrible but it isn't particularly compelling either.  Probably the most interesting thing is how different it looks from the original style.

Here's another random map:

Unlike the previous maps, this one is using a pseudo-3D representation of the mountains, and no textures on the map, giving it a more modern feeling (somewhat at odds with the forests being displayed as individual trees).  The colors are muted and there are large areas of white space.  The eye is drawn first to the lower left quadrant of the map, and then to “Lechol City" in the middle right.

There aren't a lot of obvious errors in the map -- the most egregious is the “Five Toparchs" label not fitting the label box.  The creek label up near the barrier islands is also very poorly placed.  If I have any overall criticism of the map, it's that it's a little boring.  But I look at a lot of these, so maybe that's just me.

The next map out of the generator is in some ways the opposite of the previous map.  The colors are quite bold.  The ocean in particular has a deep blue color and is mottled by depth.  The land has a speckled pattern.  Mountains are not shown at all, but the geopolitical borders are shown as blurred shading.  Terrain generation has produced a large number of small islands; particularly in the lower right.  This isn't particularly realistic (and doesn't happen often) but it admittedly makes for an interesting map.  Overall the map is quite dense with labels.

There are a number of problem areas on the map.  Most notably, there are two forests labelled even though forests are not being shown!  That's simply a missing logic check.  The geopolitical borders are also odd.  First of all, I don't much like the style used here with fuzzy borders, but more importantly, the shape of the single country (“Sungon") is a little hard to fathom.  The current algorithm for creating countries has some problems that I need to address.  I'm also not fond of the lakes (near the center of the map) here.  I've written previously about the difficulties of doing lakes well, and I've never been entirely satisfied with Dragons Abound's lakes.   To my mind, lakes got worse when I switched over to generating terrain on a more detailed grid; now lakes have the kind of fractal border that some of the coast has, but I don't think this looks right on lakes.  Lakes also don't follow the terrain correctly.  That's not particularly a problem on this map, but still bugs me.  I should probably just turn lakes off altogether until I can do a better job of generating them.  At least there aren't a lot of terrible label placement problems (although “Pa's Point" is in a bad place).

So what general conclusions should I draw from this review?

First, if you have a lot of different, interacting mechanisms driven by random numbers, then it's difficult to get them to all work correctly every time.  This is made worse if many of the mechanisms are procedural generation.  In procedural generation -- or at least in my interpretation of it -- we try to create mechanisms that can generate a wide variety of different results.  Often that results in a some bad results.  When a lot of these mechanisms are used simultaneously, there's a good chance one of them will throw up a “bad" result.

There are a couple of ways to address this.  First, I can tune the procedural generation as carefully as possible to limit the bad results without (hopefully) eliminating the creative results.  Second, I can post-edit out the bad results -- I can generate maps and simply ignore the ones that I don't think are good.  In practice, I do some of both but should probably work harder on the tuning.

Second, it's clear that labeling and label placement remain difficult problems.  I've added some rudimentary interaction capability to some kinds of labels that allow me to move them or regenerate the name, but it would be useful to have that capability for every label.  Azgarr has slowly turned his map generator into an interactive tool, and while I'm not interested in doing that, I see the appeal of having those capabilities.

I'm curious to hear what other people see in the maps, both good and bad, so I hope you'll share your thoughts in the comments or on The Reddit.