ECS40  Homework 3 

ECS40 
Homework 3 
Use the handin directory hw3 to submit your work
Filling a rectangular domain with random shapes
Description
This assignment builds on the Shape class designed in HW2. In this assignment (HW3), you
will modify the implementation of the Shape class that was developed in HW2, and implement
a class Domain representing a rectangular area in the x-y plane, with functions that draw a
visual representation of the domain as a scalable vector graphics (svg) file. The svg file can be
visualized using a browser such as Firefox, Safari, Chrome or Internet Explorer.
The domain is a rectangular array of cells that can be occupied by shapes. The goal of the
assignment is to implement a program that places randomly selected shapes at random positions
on an arbitrary rectangular domain until the domain is full, and creates a graphical representation
of the domain.
Figure 1: Rendering of an svg file obtained with a 10x12 filled domain
HW3 Assignment
In HW3, you are given the files fill.cpp (which contains the main function) and the files
Shape.h and Domain.h. You should not modify these files. Your task is to implement the
class Domain by writing the file Domain.cpp and by writing a new file Shape.cpp that
implements the additional specifications given in HW3. Note that the file Shape.h is different
from the one given in HW2.
All source files should compile without warning. You should provide a Makefile in order to
be able to build the executable fill using the command
$ make
Input
Input for the fill program is provided on the command line. It does not read input from any
file.
The command line arguments of the fill program are: size_x size_y seed
size_x: size of the domain (number of cells) in the x direction
size_y: size of the domain (number of cells) in the y direction
seed: an integer used as a seed for the random number generator rand() used in fill.cpp
The program is run, for example, using the following command line:
$ ./fill 12 10 1234 output.svg
The fill program will be tested with various sizes in the range [1,15], and various seed values.
It is not necessary to test for incorrect values in the command line arguments.
You can use the fill executable with specific command line arguments, and compare your svg
output with svg output test files provided on the web site to check the functionality of your
classes. Note: the random numbers generated on different computers may differ even if the
same seed is used. Make sure to generate and compare your output on the CSIF computers.
Make sure that your program reproduces the test output exactly. Use the diff command to
compare your files with the example files. Other command line arguments will also be used
when grading your implementation. The example files are generated using the following naming
convention. For example:
$ ./fill 12 10 2 test_12_10_2.svg
Modifications of the Shape class
The Shape class should have the following features in addition to the ones defined in HW2 (see
the file Shape.h)
Additional public members of the Shape class
virtual const char* color(void) const = 0
A pure virtual member function returning a C-style string (such as e.g. “red” or “blue”) that
defines the color of the shape. The strings returned by the function should be as follows:
O cyan
I yellow
L purple
S blue
X orange
U red
int getX(int i) const
Returns the x coordinate of cell i of the shape. It is assumed that the value of the argument is
valid.
int getY(int i) const
Returns the y coordinate of cell i of the shape. It is assumed that the value of the argument is
valid.
void draw(void) const
A function that prints on stdout a sequence of statements that represent the shape in the
scalable vector graphics (svg) format. The output should consist of multiple lines, each line
representing one of the cells of the shape. Each cell should be drawn as a square of side 40
pixels, filled with the shape’s color. For example the draw() function called by a ‘S’ shape
located at position (4,2) should output the following four lines:
<rect fill="blue" stroke="black" x="160" y="80" width="40" height="40"/
<rect fill="blue" stroke="black" x="200" y="80" width="40" height="40"/
<rect fill="blue" stroke="black" x="200" y="120" width="40" height="40"/
<rect fill="blue" stroke="black" x="240" y="120" width="40" height="40"/
Specification of the Domain class
The Domain class is responsible for managing the shapes added to the domain. It has a member
function addShape which adds a shape to the domain after checking that the new shape fits
inside the domain area and does not overlap with any of the previously added shapes.
public members of the Domain class
Domain(int size_x, int size_y)
Constructor taking as arguments the horizontal and vertical size of the domain, expressed as the
number of cells in each direction.
void addShape(char type, int x, int y)
Creates a shape of appropriate type according to the type argument, and adds it to the domain.
The function should first test if the new shape fits within the domain, i.e. that all cells of the
shape are within the domain. If it doesn’t, the function should simply return and do nothing else.
Care must be taken to free any resources allocated until then.
The function should then test if the shape overlaps with any shape already present in the domain.
If there is overlap, the function should return and do nothing else. Care must be taken to free any
resources allocated until then.
bool fits(const Shape &s) const
A function that returns true if the shape s fits inside the the boundaries of the domain. (i.e. the
coordinates of all its cells satisfy x = 0, x<size_x, y=0, y<size_y) and false otherwise.
bool full(void) const
A function that returns true if the domain is full, (i.e. the sum of the sizes of all shapes present
in the domain is equal to the total number of cells), and false otherwise.
void draw(void) const
This function draws the current state of the domain by printing a complete svg document on
stdout. It should first print the following svg header:
<?xml version="1.0" encoding="utf-8" standalone="no"?
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"
<svg width="670" height="670" viewBox="0 0 650 650"
xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
<g transform="matrix(1,0,0,-1,50,650)"
Note that this header is fixed, i.e. it is independent of the domain size.
It should then draw a frame with white background defining the domain area. For example, for a
domain of 8x5 cells, the frame is drawn by printing
<rect fill="white" stroke="black" x="0" y="0" width="320" height="200"/
Note that the width and height attributes depend on the size of the domain.
It should then draw each shape on the domain by calling the shapes’ draw functions.
Finally it should print the following svg trailer:
</g
</svg
The resulting svg file can be visualized by opening it with a browser such as Firefox, Safari,
Chrome or Internet Explorer.
private members of the Domain class
const int size_x, size_y
The dimensions of the domain measured in number of cells in each direction.
vector<Shape* sList
A vector of base pointers to store pointers to the shapes added to the domain.
Submission
Create a tar file named hw3.tar containing the files fill.cpp Shape.h Shape.cpp
Domain.h Domain.cpp and Makefile. Do not compress the tar file. The Makefile should
include the necessary definitions to compile C++ files with the –Wall option. Include your
name and Student ID in a comment at the top of each file that you wrote (but not in the files
provided). Submit your project using: $ handin cs40 hw3 hw3.tar