Lab 1: Drawing with Turtles

Exploring turtle

For this part of the lab, work through as many steps as you have time for. We don't expect you to get all the way to the end!

To explore more of the possibilities of the turtle and turtleBeads libraries, we'll work on drawing a face. Below is one possibility. You and your partner have creative freedom in this task. The goal is to learn how to make shapes appear; their precise color/location/dimensions are up to you.

final face

...but to get you inspired with what else you'll be able to create, here are some scenes created by past CS111 students for this week's problem set:

(Hover a thumbnail to see a larger view)

An image of a sunset with a large orange semicircle in the background with a small navy blue silhouette or a person in a boat with a fishing rod in hand. The text in the lower right hand corner says My dad likes to fish, created by Brigitte Lee.An image of a green plant in a terra cotta pot with text reading 6CO2 + 6h20+sunlight = C6H1206 = 602!! created by Shaylie Xie and Bianey Douglas.An image of Mike Wazowski from Monsters, Inc with text saying There is more to life than scaring! created by Faith Carbajals.An image of SpongeBob Squarepants, standing in front of his pineapple house with text saying Ahoy Mateys created by Mattie Lyons.An image of mountains with a sunset in the background created by Ayla Kurdak.An image of a shark created by Carson Dennis & Cassia Schuler.An image of a bee carrying honey by Sooyeon Park.An image of the Golden Gate Bridge labeled 'Welcome to the Bay Area' by Claire Moreland & Danika HeaneyAn image of a panda's face by Toshali Goel & Katherine Guo. Text below says: 'CS 111 student/Po: How did I do? ... Professors/Master Shifu: There is now a level 0.'An image of an elephant by Laura Chin & Mari Kramer. Text below reads 'Ernst the Elephant.'


These resources will be useful whenever you're working with turtles:

Step 0: Start a new file and imports

For this task, create a new file named (make sure to save it in your lab01 folder where is, or else importing turtleBeads will not work).

As we did in the previous part, we'll need to import turtle to use drawing commands. We might as well import turtleBeads as well for the extra functions it provides. At the top of your new file, start with a comment indicating your names and the purpose of the file, and then add code to import those libraries, like this:

# Authors: Peter and Sohie
# Purpose: CS 111 lab 1 smiley face

from turtle import *
from turtleBeads import *

Step 1: Where did that turtle canvas come from?

Note that when you execute turtle commands, the canvas automatically pops up. The canvas has a default size (700x650), default color (white) and default title ('Python Turtle Graphics'). We can change these canvas properties.

Step 2: Basic shapes: Circle face

Turtle graphics can create common shapes like circles, squares, rectangles, polygons and lines. You can also add text as well.

Let's start simple with a circle— draw a new circle like this:


The radius is 250. Where is the circle centered?

Fill in the circle

You can add begin_fill() before you draw the circle and end_fill() after you draw the circle, and that will fill the circle with color.

Don't like the default fill color? Choose your own fill color

Note that you'll need to specify your color before any drawing or filling happens. To specify the fill color, you can use these commands:

At this point, your face should look something like this:

The start of the smiley face: a brown circle with a lighter tan edge, on a gray background.

Step 3: Add eyes (you decide how many and what shape/color)

Using what you learned above, add eyes on the face. You may want to use the turtleBeads teleport function to position the turtle for drawing each eye so that you don't have to worry so much about what direction to use to get the turtle where you want it to be. Experiment a bit to figure out what coordinates work best.

You can find the available turtleBeads shapes here.

You can refer to the available turtle colors page to pick your eye color(s) of choice.

Face with eyes added: two blue ellipes are now present in the top half of the brown circle, with different shades of blue and different thicknesses for their black borders.

Note: Drawing faster

As you add more pieces to your face, it becomes harder and harder to work with since you have to wait a while to see what gets drawn. You can use the speed function to control how fast the turtle moves, but this has limits. To draw things instantly, you can use the noTrace from turtleBeads before you start drawing, but if you do that, you must use showPicture at the end of your code or Python may randomly decide to skip some of your commands.

If you still want to watch the turtle move for part of your picture, put showPicture before the part you want to watch being drawn, and also add a call to doTrace to resume normal drawing.

Step 4: Make a hat (use rectangles or lines)

Using the turtle shapes documentation, and what you learned about circles above, create a hat made of one or more rectangles.

Rectangular hat examples:

Smiley Hat: The same face with a hat on top composed of two rectangles: a long thin one and a shorter thicker one that overlaps the thin one above it in the middle. Smiley Hat 2: The same image but now with the hat tilted slightly clockwise.

Simple line hat:

Smiley Hat 3: The same brown circle face with a triangular hat that has three ellipses on top to make a pom pom.

This hat uses simple lines (forward, backward and left and right turns) with a three-ellipse pom pom on top.

Step 5: A mouth and a nose

To create a curved “half moon” shape for the mouth, we'll get creative by overlapping two circles like so:

mouth1: a full red circle. mouth2: The same circle but now there's a brown circle on top, offset slightly to the north. The brown circle is the same color as the background of the face. mouth3: The brown circle is now filled in, leaving a crescent of the red circle underneath visible.

We start will a full red circle. Then we overlap another circle on top of the first circle, and we fill the second circle with the face color. This makes our top circle blend in nicely with the face as if it's not even there, like this:

The same brown face with eyes described above, now with the addition of an orange circle in the middle for a nose and a red crescent in the bottom half for a smile.

Note that you need to add the nose after the mouth, otherwise, the "cover up" mouth circle will hide the nose. The most recently drawn turtle shapes will appear on top of previously drawn shapes.

Step 6: Add a caption

For our finishing touches, let's add some text to our smiley face. Position your turtle where you would like the text to appear, and then use the drawText command like this:

drawText("I love CS111")

Can't see your text? What color is it? Where was your turtle positioned when you wrote? Is it showing up tiny, like this?

text1: Very tiny white text below the face described above. It's so tiny that only someone who zooms in very far or who can read this alt text will know that it says: 'i love cs111'.

You can make the font bigger like this:

drawText("I love CS111")
text2: The same text ('i love cs111') in a larger font centered below the face desicrbed above.

Step 7: How about some hair?

You have lots of option for head and/or facial hair: thick or thin lines, filled circles, or overlapping ellipses. Have some fun and add some hair to your face.

hair1: The same face described above, now with two overlapping angled blue-green ellipses on the top to represent hair. hair2: The same face described above, excpet instead of the two ellipses, there are many overlapping pink circles placed around the entire top half of the circle to represent fuzzy pink hair.

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