You must complete the code provided so that it works as follows:

Use the previous task to build upon this task:

Ruby Code provided:

require 'gosu'

module ZOrder

BACKGROUND, MIDDLE, TOP = *0..2

end

MAP_WIDTH = 200

MAP_HEIGHT = 200

CELL_DIM = 20

class Cell

# have a pointer to the neighbouring cells

attr_accessor :north, :south, :east, :west, :vacant, :visited, :on_path

def initialize()

# Set the pointers to nil

@north = nil

@south = nil

@east = nil

@west = nil

# record whether this cell is vacant

# default is not vacant i.e is a wall.

@vacant = false

# this stops cycles - set when you travel through a cell

@visited = false

@on_path = false

end

end

# Instructions:

# Left click on cells to create a maze with at least one path moving from

# left to right. The right click on a cell for the program to find a path

# through the maze. When a path is found it will be displayed in red.

class GameWindow

# initialize creates a window with a width an a height

# and a caption. It also sets up any variables to be used.

# This is procedure i.e the return value is 'undefined'

def initialize

super MAP_WIDTH, MAP_HEIGHT, false

self.caption = "Map Creation"

@path = nil

x_cell_count = MAP_WIDTH / CELL_DIM

y_cell_count = MAP_HEIGHT / CELL_DIM

@columns = Array.new(x_cell_count)

column_index = 0

# first create cells for each position

while (column_index

row = Array.new(y_cell_count)

@columns[column_index] = row

row_index = 0

while (row_index

cell = Cell.new()

@columns[column_index][row_index] = cell

row_index += 1

end

column_index += 1

end

# now set up the neighbour links

# You need to do this using a while loop with another

# nested while loop inside.

end

# this is called by Gosu to see if should show the cursor (or mouse)

def needs_cursor?

true

end

# Returns an array of the cell x and y coordinates that were clicked on

def mouse_over_cell(mouse_x, mouse_y)

if mouse_x

cell_x = 0

else

cell_x = (mouse_x / CELL_DIM).to_i

end

if mouse_y

cell_y = 0

else

cell_y = (mouse_y / CELL_DIM).to_i

end

[cell_x, cell_y]

end

# start a recursive search for paths from the selected cell

# it searches till it hits the East 'wall' then stops

# it does not necessarily find the shortest path

# Completing this function is NOT NECESSARY for the Maze Creation task

# complete the following for the Maze Search task - after

# we cover Recusion in the lectures.

# But you DO need to complete it later for the Maze Search task

def search(cell_x ,cell_y)

dead_end = false

path_found = false

if (cell_x == ((MAP_WIDTH / CELL_DIM) - 1))

if (ARGV.length > 0) # debug

puts "End of one path x: " + cell_x.to_s + " y: " + cell_y.to_s

end

[[cell_x,cell_y]] # We are at the east wall - exit

else

north_path = nil

west_path = nil

east_path = nil

south_path = nil

if (ARGV.length > 0) # debug

puts "Searching. In cell x: " + cell_x.to_s + " y: " + cell_y.to_s

end

# INSERT MISSING CODE HERE!! You need to have 4 'if' tests to

# check each surrounding cell. Make use of the attributes for

# cells such as vacant, visited and on_path.

# Cells on the outer boundaries will always have a nil on the

# boundary side

# pick one of the possible paths that is not nil (if any):

if (north_path != nil)

path = north_path

elsif (south_path != nil)

path = south_path

elsif (east_path != nil)

path = east_path

elsif (west_path != nil)

path = west_path

end

# A path was found:

if (path != nil)

if (ARGV.length > 0) # debug

puts "Added x: " + cell_x.to_s + " y: " + cell_y.to_s

end

[[cell_x,cell_y]].concat(path)

else

if (ARGV.length > 0) # debug

puts "Dead end x: " + cell_x.to_s + " y: " + cell_y.to_s

end

nil # dead end

end

end

end

# Reacts to button press

# left button marks a cell vacant

# Right button starts a path search from the clicked cell

def button_down(id)

case id

when Gosu::MsLeft

cell = mouse_over_cell(mouse_x, mouse_y)

if (ARGV.length > 0) # debug

puts("Cell clicked on is x: " + cell[0].to_s + " y: " + cell[1].to_s)

end

@columns[cell[0]][cell[1]].vacant = true

when Gosu::MsRight

cell = mouse_over_cell(mouse_x, mouse_y)

@path = search(cell[0],cell[1])

end

end

# This will walk along the path setting the on_path for each cell

# to true. Then draw checks this and displays them a red colour.

def walk(path)

index = path.length

count = 0

while (count

cell = path[count]

@columns[cell[0]][cell[1]].on_path = true

count += 1

end

end

# Put any work you want done in update

# This is a procedure i.e the return value is 'undefined'

def update

if (@path != nil)

if (ARGV.length > 0) # debug

puts "Displaying path"

puts @path.to_s

end

walk(@path)

@path = nil

end

end

# Draw (or Redraw) the window

# This is procedure i.e the return value is 'undefined'

def draw

index = 0

x_loc = 0;

y_loc = 0;

x_cell_count = MAP_WIDTH / CELL_DIM

y_cell_count = MAP_HEIGHT / CELL_DIM

column_index = 0

while (column_index

row_index = 0

while (row_index

if (@columns[column_index][row_index].vacant)

color = Gosu::Color::YELLOW

else

color = Gosu::Color::GREEN

end

if (@columns[column_index][row_index].on_path)

color = Gosu::Color::RED

end

Gosu.draw_rect(column_index * CELL_DIM, row_index * CELL_DIM, CELL_DIM, CELL_DIM, color, ZOrder::TOP, mode=:default)

row_index += 1

end

column_index += 1

end

end

end

window = GameWindow.new

window.show

Please provide a satisfactory response, and I will thumb up your response. Any unsatisfactory response will be reported.

You must complete the code provided so that it works as follows: Step 1: The code in the initialize() procedure of the window should be completed to set up cells that are connected to each other with variables joining each cell to its neighbours (using references). Step 2: The user should be able to left-click on cells on the screen to create mazes (and later in the Maze Search task we will use recursion to find a path through the maze). Step 3: Each cell clicked on should turn yellow. Step 4: Once this is working (or perhaps before) add code to print out each cell and indicate whether the reference to the neighbour on each side is nil or not, as per the following: Cellx:0,y:north:south:1east:1west: In this case, there is no neighbour to the north or the west. (i) Note: Whether the east or the west neighbour is nil will depend on your perspective, i.e. is your perspective looking into the screen, or out of the screen. Your submitted screenshot should look something like the following: (b) Stop Online (1) maze_creation.rb NOTE: You cannot run Graphical programs in this tool - you need to copy the provided code to your IDE and run it on a computer with GOSU installed. Use the code you completed in Week 4, task 4.4D to get started. Complete the code so that it works as follows: Once the user has used the Left Mouse Key to create at least one path from one side of the screen to the other, the user should then be able to Right-Click the mouse on a yellow cell on the leftmost side of the screen. The program should then search using the recursive search() function to find a path to the right side of the screen following one of the user's created paths. Each cell on the path should then be displayed in red. A found path through the maze may look something like this: Resources The following resources will be able to support you with this challenge: (Sobkowicz 2015, pp. 101-123) to help with the grid aspect of the maze task. Rubydoc 2020). - Gosu (Raschke et al. 2020). - Watch the following video tutorial: Ruby Conf 2016 - Attention Rubyists: you can write video games by Cory Chamblin (Confreaks 2016)