Monday, March 21, 2005

Round and Round and Round she goes...

Of the 40+ Scenario maps that we include with Supreme Ruler 2010, there is one that is unique compared to the rest. In the program code I refer to it as the top level map, but in discussion it is simply called "The World".

The World Map has a few unique features to it. First, and most obviously, it is our largest map, at 900 hexes wide. Not the type of map you'll be able to play an conquer in a single night. The world is a big place.

Secondly, it is our only map where there is no 'external' World Market organization. In each sub map there is an off-map force - the new "UN" - that controls external trade and also gets involved with subsidies, military interventions, sale of arms, and so on. (Much like the United States does today.) In the World Level, what you see is what you get - the borders of the sandbox are defined, and nobody can come to help if you start getting beat up by the bullies.

However, the biggest internal engine difference is the fact that, unfortunately, the world is not flat. Ignoring for now the protestations of the Flat Earth Society (http://www.flat-earth.org/), the world has this roundness to it that is a challenge to represent in a strategy game. Some games have pulled it off, but nothing with the complexity of detail that SR2010 stores about the world. Even just moving around - internally units use a very sophisticated "A* Path Search Algorithm" that can scan thousands of possible paths to determine the best way to get from point A to B. We don't just take into account terrain, but add in unit movement types, bridges and bridging units, supply zones, transit treaties, and a few other elements, and you have a pretty complex process. Now you also need to toss in the fact that you can go off one end of the map and appear on the other - or more precisely, you just keep going round and round.

This 'wraparound' implementation is something that has just been, well, "wrapped up", and is being incorporated into the game engine. It works pretty well, though there are a number of oddities to address (such as the mini-map display). Of course, this isn't really a "round" world, since we only allow East-West scrolling. North/South scrolling would just be too confusing to the player, and so it really isn't worth attempting. (For example, if you scroll up from North America without changing viewpoint you would end up seeing Europe upside down, etc). Maybe someday we'll do a truly round tactical world, and really give the A* pathing a workout...

So, welcome to the Cylindrical World of Supreme Ruler 2010...

-- George.