Examples

The examples in this directory are meant to help teach you about different aspects of the turtle crate. Each example shows a different way of using it to create a drawing.

Examples range from "beginner" to "advanced". This rating is subjective and subject to change, so you may find that you're able to understand examples in one of the higher categories even if you're still learning. The examples listed here are just a few of the more prominent ones from the crate. See the other files in the examples directory for even more.

Table of Contents

• Beginner
• Intermediate
• Advanced

Level: Beginner

Simple Square

Source Code: square.rs

This program draws a square on the canvas by repeatedly calling the forward and right methods.

Simple Circle

Source Code: circle.rs

This circle is drawn using many small lines and short turns. It's hard to tell just by looking at it, but it isn't actually perfectly round!

Dashed Circle

Source Code: dashed_circle.rs

This image is drawn using the pen_up and pen_down methods to periodically lift the pen as the turtle moves around the circle. The code uses integer division as well as the remainder operator to figure out when to lift and lower the pen.

Radioactive Triangles

Source Code: three-triangles.rs

Draws three equilateral triangles and shows how the program for a single triangle can be reused to draw several of them.

Five-pointed Star

Source Code: empty_star.rs

A five-pointed star with no lines in the middle. The background color is changed from the default white and the pen size and pen color are changed as well. This is done using the set_background_color, set_pen_size, and set_pen_color methods respectively.

Level: Intermediate

Square-petalled Flower

Source Code: squares.rs

This program repeatedly draws squares while rotating the turtle to produce a square-petalled flower. The red and white squares are colored using the set_fill_color, begin_fill and end_fill methods.

Isometric Nested Cubes

Source Code: nestedcubes.rs

This example draws a hexagonal spiral with a fading color that alternates between blue and white. It creates an illusion of nested three-dimensional cubes isometrically projected onto the two-dimensional space of the canvas.

Randomly-colored Tornado

Source Code: coloredridge.rs

This example varies the pen size and color as the turtle moves. The size is set to the value of a gaussian function and random pen colors are used to ensure that you'll get a completely different image every time.

Heart

Source Code: heart.rs

A cute drawing of a heart. The arcs are more difficult to draw than you might expect!

Rust Logo

Source Code: rust.rs

A (simplified) version of the logo for the Rust programming language.

Snowman

Source Code: snowman.rs

A nice-looking snowman with all its common features.

Turtle

Source Code: draw_turtle.rs

A turtle drawn by... a turtle!

Ferris

Source Code: ferris.rs

Draws the officially unofficial mascot of the Rust language: Ferris in the "happy" version! It uses cubic Bézier curves extensively.

Level: Advanced

Heighway Dragon Curve

Source Code: dragon.rs

Draws a Heighway dragon curve. This self-similar fractal curve is generated by recursively unfolding a line by 90°. Step 1 is to draw a line segment. Step 2 is to duplicate the line segment from Step 1 and rotate it by 90° along one of its extremities to create a new extremity. You repeat the process using the new extremity and continue along to generate each line.

Sierpiński Triangle

Source Code: sierpinski-triangle.rs

Draws a Sierpiński triangle The Sierpiński triangle is another recursively drawn self-similar shape. It consists of many nested equilateral triangles, each containing three, one in every corner.

Square Fractal Tree

Source Code: tree.rs

This is a tree-like fractal curve where the trunks or branches are squares rather than lines. The sizes are chosen to make two squares' vertices coincide.

Von Koch Snowflake

Source Code: snowflake.rs

Draws a Von Koch snowflake. This uses yet another recursive algorithm: Step 1 is an equilateral triangle. Step 2 is cutting each of its sides in three and replacing their middle parts with an equilateral triangle with sides of the same length as the surrounding parts but without a base side. Step n + 1 is repeating the process for each side of step n. Note there is no "cutting" happening during the drawing, all the drawn sides are the same length, but the turning angles are computed recursively following the described algorithm.

Random Maze Generator + Solver

Source Code: maze/main.rs

In this example, the turtle generates and draws a maze. Then, it goes through and solves the maze by moving through the passages until it finds the exit.