PJ00 - Turtle Scene


In this project you will design a structured program and a beautifully artistic scene painted painstakingly on your screen, and ours, by our little Turtle friends.

Before beginning this project, you should complete the Turtle Graphics Introduction Tutorial.

The scene you choose to create should have some element in it that repeats / is reused at least three times. Perhaps it’s a forest of trees, or a house with many windows, or a flock of birds scattered in the distance, maybe it’s stars in the night sky, or snowflakes floating fancily about. Pick a scene that sparks joy and transports you to a place of hygge and happiness.

If you need inspiration, look no further. Remember, when learning how to program there are no mistakes, just happy, little accidents.

Learning Objectives

  1. You will gain experience breaking a complex task you want to achieve into smaller, parameterized functions. This technique is called problem decomposition.
  2. You will gain experience passing objects to functions and becoming more comfortable with the idea of procedures.
  3. You will gain experience reading official documentation in order to achieve your vision without knowing exactly what tools you have available at the onset.
  4. You will produce a program that is longer and more involved than any of the earlier exercises.


This is an open-ended project and we encourage both exploration and pushing yourself. Follow these guidelines to get the most out of the project:

  1. Define at least four separate procedures whose purpose is to draw visual components of your scene and are meaningfully named to describe what component they’ll draw. These procedures must make use of at least three parameters: one Turtle object parameter and two float parameters for the x and y coordinates of where to start drawing the component on your canvas. You are encouraged to implement other “helper” procedures that abstract simpler ideas for use in your required procedures (for example, a procedure that draws a line between any two coordinates or a rectangle procedure). For this project you should use the turtle package’s object-oriented interface as shown in the tutorial and the examples of this document.

  2. Have a main procedure whose purpose is to construct any Turtle objects and make use of the component procedures described in the previous requirement to place the components of your scene. It does not need to take any parameters. After your functions are all defined, including main, you should use the if __name__ == "__main__": idiom demonstrated in Lesson 12 - Magic 8-Ball Tutorial.

  3. Call at least one of your four required component procedures twice to place that component twice in your scene in different locations.

  4. Use a while loop to avoid repetitive code in some part of your scene.

  5. Fill at least one shape in your scene with a color other than white.

  6. Change the marker’s tracing color for at least one shape in your scene to something other than black. This is demonstrated in the Turtle Tutorial.

  7. Static Types - Be sure to specify each function’s parameter’s types and return type.

  8. Linting: Good, Pythonic style - refer to the Style Guide for help.

  9. Use effortful and meaningfully descriptive docstring documentation for the module (top of file) and each function definition.

  10. Avoid any single function from becoming too complex. When programming in general, if you find yourself writing a very complex function, it’s likely you should break it down further into simpler functions. Break your most complex component procedure besides main down further into simpler, but still meaningfully named procedures. Your component procedure should call these simpler procedures.

  11. Impress us by trying out something you find interesting! Describe what you are attempting here in the file’s docstring. Remember, a docstring can span more than one line, it just ends with the """. Some ideas you could try for here:

  • Read through the Turtle documentation page to find a function to use that we did not make use of in the turtle tutorial and make use of it in your project: https://docs.python.org/3.8/library/turtle.html#turtle-methods
  • Use loops and procedures in clever ways to draw an interesting pattern or complex component
  • Make clever use of randomness in your scene by using a function imported from the random module: https://docs.python.org/3.8/library/random.html
  • Go above and beyond with a scene more complex than could be achieved with only four components added to it.

It is worth noting it is very ok, and perhaps expected, for your scene to look like a drawing you might have been proud of in kindergarten. Such is the nature of doing art on a medium you’re new to. The end visual result is less interesting than the process by which you got there.

Getting started

In your course workspace, expand the projects. Right click in projects and add a file named pj00_turtle_scene.py.

You can use the following template to begin your program. Unlike the tutorial, you will need to write functions which control your scene.

We’ll begin by adding a main function that takes no parameters and, since it is a procedure has a return type of None.

To give you an example of what is expected in your four “component” procedures, consider this one that draws a square and adds an additional parameter for you to control the width of the square:

Your component procedures, and any other “helper” functions you define, can add whatever additional parameters you’d like. Notice that parameters tend to give your procedures extra flexibility. If the draw_square function did not have a width parameter, then it could only draw squares of the exact same, “hard-coded” width.

The Turtle object’s setheading method takes a float value that is the degrees to face the turtle in. So, in the example above, each time the draw_square procedure is called the turtle’s heading is reset to head toward 0.0 degrees (along the x-axis headed in a positive direction). Since your component procedures do not know the starting position of the turtle or the direction it is heading in, you will likely benefit from using goto and setheading to move it and face it in the direction you’d like.

After defining this procedure we could call it from the body of the main function to draw a few squares. For example, by replacing ... with the following Turtle variable construction and draw_square() calls:

Have fun, get creative!

Frequently Asked Questions

How can I get my scene to render faster?

Start by increasing your Turtle object’s speed to the maximum speed. For example, if you have a Turtle variable named bob, you could increase its speed with bob.speed(MAX_SPEED) where MAX_SPEED is a constant set to 0 per the official documentation.

Once you have the hang of writing procedures and a feel for how interacting with Turtle objects work, you can further supercharge your Turtle with some “hacks”. By default the Turtle renderer will update the scene as your method calls occur. However, for complex scenes it’s often desireable to have the scene drawn instantaneously. To do so we will disable the tracer from updating until your scene is completed. You will need to import the functions tracer and update from the turtle package, alongside done and colormode. Then, you can update your main function to turn off tracing and update after your scene instructions complete: