In the last entry, I discussed the challenges of producing logical text adventure maps based on real geography; in this case, the physical geography of the city of Williamsburg in the late 1700s. The good news is that the streets and main building locations have been preserved, which helps in map development. But the challenges of using a real place that needs to be reproduced in the context of an adventure game map are even more challenging when using exisitng building architecture. The constraints of walls, doors, hallways, rooms, and stairs along with their comparative physical location relationships don’t leave much room for “adventure navigation license.” The biggest challenge is in using the compass rose as a foundation for navigation, where you have 8 directions of movement from any particular point (north, northeast, east, southeast, etc.). Add “up” and “down” for a total of 10 basic commands that can be typed to specify movement. Consider the following diagram:
The player location can represent anywhere in physical space: a forest clearing, a small cave chamber, a grand ballroom. Adding the “up” and “down” directions provides a good deal of movement options including 3-dimensional flexibility, for a total of 10 choices for player movement from any given location in the game. However, particular real locations can be difficult to reproducing using the compass rose navigational framework without making overly compromising game navigation decisions. For example, suppose we’re dealing with a long hallway with many doors on both sides, like a hotel hallway:
We can see here that a single “location” representing the hallway is not a practical solution to get to the individual hotel rooms; there four north directional choices and four choices for going south. While creative programming can help (“enter room 101,” “enter room 103,” “enter room 105,” etc.), that approach tends to add to the command complexity for what should be one of the easier tasks in Interactive Fiction play: moving from one spot to another. A different approach might be to segment the hallway:
Using this approach, we see that using the compass rose commands are sufficient for us to navigate to any location on the map without any amiguity. But there’s a tradeoff in that getting from Hall Location 1 to the room in the far northeastern corner would take five steps in the game. The can be tediuos for the player, especially if there is not a particularly great amount of game content to be discovered in each of those Hallway locations.
It is this navigation design issue that is driving the development of the building interior set of game maps. Some creativity allows us to “bend” the compass rose directions to suit our needs, for example:
Here we have a location that could be a hallway, with accesssibility to three doors on the northern face of the hall and three doors on the southern face. We would need to address this layout in the text description of the location, something like, “You are in an east-west running corridor with six doors total on the northern and southern walls. North of you is a single door, and you likewise see doors on the northwest corner as well as the northeast corner of the corridor. The southern wall has the same arrangement of doors.”
As work progresses on developing the Williamsburg buildings’ intererior maps, it is this interpretation of the compass rose that allows us to achieve an acceptable level of architectural fidelity. The Governor’s Palace is easily one of the most complex structures being reproduced within the game, and it is also one of the key narrative locations. There are four floors to the Palace, and the maps are displayed below:
First Floor (source map here):
Third Floor (source here):
Basement (source here):
This mapping structure gives a total of 44 separate player locations for the game, but remember that these 44 locations are at the single Governor’s Palace location on the overall physical map. There are still quite a few buildings to map (which means researching all the architectural plans from the Colonial Williamsburg Library. Lots of fun in the days ahead!
Developing a map for an Interactive Fiction environment can be challenging especially if the game is based on real-world geography, as is the Historical Williamsburg Living Narrative. A large part of the value of this game is the historical accuracy–which not only includes the events of the time but the geography and architecture as well. In designing the game map, I am considering external landscape and building floor plans separately, and here I describe the process by which the external landscape portion of the game map was developed.
I started working from the map provided by the Colonial Williamsburg Foundation for guests visiting the city. Below is a scanned version of that map, already partially “cleaned up” (that is, much of the extraneous information–modern buildings, bus route lines, restroom symbols, etc.–have already been removed). After working with this map for a brief period of time, I found a few characteristics I didn’t like. Most significantly, there wasn’t a sufficient level of detail regarding building shapes and grounds, and the relative sizes, locations, and distances between buildings wasn’t accurate enough for me to use in creating descriptions.
At this point I changed my approach. In order to ensure fidelity to the actual physical layout of Williamsburg, I decided to use satellite imagery for the initial layout work. Google Maps provided excellent resolution from the Governor’s Palace in the north to the Public Hospital in the south, and the College of William and Mary in the west to Christiana Campbell’s Tavern in the east. The city’s overall layout was depicted quite clearly.
Once I had an accurate map from which to work, I was able to select the significant buildings, associated grounds, and pathways between that the player would be using. I superimposed this image on top of the map, and this gave me the level of detail I wanted for development.
Peeling away the city map, this is what the initial pass at the game map looks like. While this map contains all the information needed to create accurate location descriptions (for example, it will be important to note the distance of the College of William and Mary from the city proper), this version of the map is a bit difficult to work from in building the Interactive Fiction navigation scheme. For that task, a logical map is more appropriate.
This logical map was built from the physical line map (above), connecting locations using only the eight compass directions, and not taking into consideration the sizes of buildings or their actual distance from each other. Also, no assumptions can be made between “nodes” in the map below if they are not connected by a direction line. In other words, if a node is to the west of another node, but they are not connected by an east-west line, they may not be precisely east and west of each other. This map simplifies and compresses the physical map information for ease of navigation programming. The yellow nodes represent place locations where the player may go, while the blue nodes represent buildings or structures that have additional rooms or internal locations not depicted here. Those additional locations will be represented in further mapping exercises.
By using this logical map along with the visual information obtained from the line map superimposed from the Google satellite image, I will be able to create rich in-game descriptions of the physical Williamsburg environment. For example, an east-west running path on the logical map may actually be a long, curved road on a hilly slope, and that level of detail will be captured in the game for a rich and hopefully satisfying experience.