Project 2: A Shape Collection

Main course Moodle page

The goal of this assignment is to give you practice in creating and using functions and function parameters in python. You'll continue to create shapes using turtle graphics, just like we did in lab.

The end result of the assignment should be a representation of an outdoor scene in your favorite town or city.

Remember that you need to write hte code yourself. You can discuss the assignment and ideas regarding the assignment with others in English, but not Python. If you have questions about your python (other than very simple syntax questions), please ask one of the lab assistants or professors. Please see the syllabus for guidelines on collaboration and attribution.

Tasks

Make a copy of your lab2.py file and rename it shapes.py. Delete the main code from the file so that only the import statements and the functions remain. You should not have any top level code in the shapes.py file. It is meant to form a library of shape-drawing functions that other code files will be able to import and use.
Your first task is to create a main.py file that imports your shapes.py functions. To do this, create a file called main.py in a text editor, and at the top (after your name and a date) put the following.
```
import shapes
```
In your main.py file, make a function called town1. Put a single call to the town1 function at the end of the file, followed by a raw_input call.

Write some python code in your town1 function that calls some of the functions from your shapes.py file to draw a simple image (like a few blocks). Note that to call a function from your shapes file you have to prepend shapes. in front of the function name. For example shapes.block( 10, 10, 20, 30 ) would be how you would call the block function.

You can run your main.py file using:

python main.py

You don't need to save this image, as you'll be replacing the code in the town1 function later on.
In your shapes.py file, make 2 more functions for drawing basic shapes like the block function from lab. Basic shapes should take in at least an x location, y location, and size information. For example, you could make a triangle function or a hexagon function with the size value being the length of a side, in pixels . Put a print statement at the beginning of each function and test them out by calling the functions in your main.py function.
Each of your shapes should draw properly no matter where it is drawn on the screen, what the size parameter is, or what the orientation of the turtle happens to be when the shape function executes. Test this out for all of your functions.

In your writeup, include a picture demonstrating that your shape functions work properly. This is required picture 1.

When you have a picture or scene you want to save, make a screen capture of it on a mac using the key combination command-shift-4. The picture will automatically be saved to a file on your Desktop. You can then move and rename it to a more appropriate location. Make sure the entire scene is visible in the image.
In the shapes.py file, make 2 functions that draw iconic versions of more complex things that are going to be in your scene. These aggregate shapes might be a bench, a tree, or a building. They should incorporate several of the simpler shapes from your library.
When you define these aggregate shape functions, they should all take at least three parameters. The first two (x0, y0) will define the starting location for the shape and the third should define the scale of the shape. A scale factor of 1.0 should draw the shape in its natural size. Feel free to add additional parameters as you like to control other aspects of the shape. As with the basic shapes, your shapes should draw properly at any scale, location, or turtle orientation.

For a little more detail on making aggregate shapes, see the geometric thinking page.

In both of of your new functions, use one or more of the basic shape functions to draw the shape. For example, a building might incorporate the block and triangle functions. Test out your new functions before proceeding.

In your writeup, include a picture demonstrating that each of your aggregate shape functions work properly. This is required picture 2.
Now it is time to replace the code in your town1 function. Using the functions you created in steps 2 and 3, make an outdoor scene from your favorite town or city. In your scene, make use of the fact that your functions can draw the shapes with different sizes in different locations. You can also use the random package and for loops to make more complex scenes.
Save the image and include it in your writeup. This is required picture 3.
Make a second town or city scene in a function town2 in your main.py file. This one can be either and outdoor or indoor scene.
Save the image and include it in your writeup. This is required picture 4.

Extensions

Each assignment will have a set of suggested extensions. The required tasks constitute about 85% of the assignment, and if you do only the required tasks and do them well you will earn a B+. To earn a higher grade, you need to undertake one or more extensions. The difficulty and quality of the extension or extensions will determine your final grade for the assignment. One complex extension, done well, or 2-3 simple extensions are typical.

Make additional basic or complex shape functions that make use of your other shape functions.
Make additional scenes that show creative use of functions, loops, or randomness.
Make use of the for loop control structure from the lab (you can also read ahead in the book).
Make use of the random package to make your scene more interesting. For example, if you import the random package into your program:
import random
Then you can use it to generate random integers using the following expression, where a and b are the upper and lower bounds of the random numbers you want.
random.randint(a, b)
Make use of other turtle properties such as line width, color, and fill capability to make your shapes more interesting.
Add additional parameters to your shapes to control properties like line width and color.
Use a Python feature that is new to you.

Writeup and Hand-in

Turn in your code by putting it into your private handin directory on the Courses server. All files should be organized in a folder titled "Proj2" and you should include only those files necessary to run the program. We will grade all files turned in, so please do not turn in old, non-working, versions of files.

Make a new wiki page for your assignment. Put the label cs151s13project2 in the label field on the bottom of the page. But give the page a meaningful title (e.g. Stephanie's project 2).

In general, your intended audience for your write-up is your peers not in the class. Your goal should be to be able to use it to explain to friends what you accomplished in this project and to give them a sense of how you did it. Follow the outline below.

A brief summary of the task, in your own words. This should be no more than a few sentences. Give the reader context and identify the key purpose of the assignment.
A description of your solution to the tasks, including any images you created. This should be a description of the form and functionality of your final code. You may want to incorporate code snippets in your description to point out relevant features. Note any unique computational solutions you developed. Code snippets should be small segments of code--usually less than a whole function--that demonstrate a particular concept. If you find yourself including more than 5-10 lines of code, it's probably not a snippet.
A description of any extensions you undertook, including images demonstrating those extensions. If you added any modules, functions, or other design components, note their structure and the algorithms you used.
A brief description (1-3 sentences) of what you learned.
Don't forget to label your writeup so that it is easy for others to find. For this lab, use cs151s13project2