Provides a set of functions to make tracking the hidden movements of the 'Jack' player easier. By tracking every possible path Jack might have traveled from the point of the initial murder including special movement such as through alleyways and via carriages, the police can more accurately narrow the field of their search. Additionally, by tracking all possible hideouts from round to round, rounds 3 and 4 should have a vastly reduced field of search.
A set of functions for tracking the hidden movement of 'Jack' in the board game Letters from Whitechapel by Fantasy Flight Games
There are many reasons you may want to install this package.
#Install the latest version from GitHub#devtools::install_github("bmewing/whitechapelR")
This package contains a number of functions which, when used together, allow you to map out all the possible places where Jack might be and narrow your field of search.
Each round you must indicated where the first murder occurred. This is done with the
start_round() function which takes as it's only argument the space(s) of the murder. The result needs to be peserved.
paths = start_round(64)
As Jack moves, you'll need to monitor where he might possibly be. There are two functions which help with this,
take_a_carriage (which is a wrapper for
take_a_step). Taking a step requires that we provide the list of all possible paths taken up to this point and which graph Jack is currently using. By default, he uses the
roads graph but when using a lantern he uses the
alley graph. These are both included in the package by default.
#if taking a normal steppaths = take_a_step(paths,roads)#if taking a latern special movement# paths = take_a_step(paths,alley)
Additionally, you may specify via a list of blocked nodes where Jack cannot move due to being blocked by a policeman. Note, policemen cannot block alley movement but this is not hardcoded into the function, so you could possibly mess up your information at this point.
#if policemen are blocking the road between 50 and 31 as well as between 30 and 13# paths = take_a_step(paths,roads,list(c(50,31),c(30,13)))
Taking a carriage can only be over roads and is never blocked by policemen so it is a simple wrapper for taking two steps with the added functionality of following the rule where Jack cannot end his movement on the space where he began it.
# paths = take_a_carriage(paths)
As a policeman searching for clues, you want to be able to modify possible paths based on the evidence you aquire. This is done with the
inspect_space function. It requires the list of all possible paths, the space(s) inspected and a boolean indicating what was found. Because of the exhaustive nature of the methods here, not finding anything can still be incredibly informative.
#if no clue was foundpaths = inspect_space(paths,c(50,30),FALSE)paths = inspect_space(paths,64,TRUE)
It should be pointed out that the algorithms assume you never make mistakes. Finding a clue simply eliminates all paths which do not contain that number. If you input a space which Jack could never have visited and indicate you found a clue there, the path set will be reduced to 0 and you'll have no information from which to work. There is no undo function here.
Once Jack has (irritatingly) successfully made it their hideout, you want to track which spaces are candidates and improve that information over time. This is done with the
end_round function. By storing the endpoints of all possible paths in a variable (say
hideouts), future rounds can use the intersection of these endpoints and previous information to, hopefully, reduce the possible spaces to a manageable number.
# at the end of the first roundhideouts = end_round(paths)# at the end of subsequent rounds# hidouts = end_round(paths,hideouts)
The final utility to mention here is the
show_board funtion which produces an igraph representation of the game board with the appropriately numbered nodes in their identical positions. Nodes are colored based on the proportion of possible paths which flow through them (key areas to focus on) and can also highlight where hideouts might be.