Detailed Turtle Graphics Study Notes

Importing the Turtle Module
- Use the command: import turtle
- Initializes the turtle graphics module for use.
Creating a Screen Object
- Syntax: screen = turtle.Screen()
- Sets up a screen where graphics will be drawn.
Creating a Turtle Object
- Syntax: turtle = turtle.Turtle()
- Initializes a turtle that can draw on the screen.
Exiting the Program
- Use: screen.exitonclick()
- Keeps the window open until clicked, useful for debugging.

Order of Commands
- Import turtle module > Initialize screen > Initialize turtle > Your drawing commands > screen.exitonclick().
- Important to get this order correct for the program to function properly.
Cartesian Plane Explanation
- The turtle starts at the origin (0,0).
- The x-axis runs horizontally (right is positive, left is negative).
- The y-axis runs vertically (up is positive, down is negative).

Basic Movement Methods
- All use dot notation: turtle_name.method(arguments)
- Common methods include:
- forward(pixels)
  - Moves the turtle forward by a specified number of pixels in the direction it is currently facing.
- left(degrees)
  - Rotates the turtle left (counterclockwise) by the specified number of degrees.
- right(degrees)
  - Rotates the turtle right (clockwise) by the specified number of degrees.
Heading Control
- setheading(angle)
- Sets the orientation of the turtle to a specific angle measured from the (0,0) point (where 0 degrees is to the right).
- Angles:
  - 0°: Right
  - 90°: Up
  - 180°: Left
  - 270°: Down
Pen Control
- penup() - Lifts the turtle's pen (no line drawn).
- pendown() - Lowers the turtle's pen (draws a line).

Example Drawing Sequence:
- Initial Position: Turtle (e.g., Fred) at origin facing right.
- Commands:
- fred.forward(150) moves forward by 150 pixels.
- fred.left(90) turns left 90 degrees.
- fred.forward(150) moves up 150 pixels.
- fred.right(90) turns right, facing up.
- fred.forward(150) moves forward 150 pixels.
- Results in a shape drawn based on these commands.

Creating Shapes
- circle(radius)
- Draws a circle of specified radius.
- Circle direction influenced by current turtle heading.
Pen Size and Color
- pensize(width)
- Sets the width of the pen in pixels.
- pencolor(color)
- Sets the pen color (accepts string name of color).
- Available Colors: red, orange, yellow, green, blue, purple, pink, etc.
Positioning with goto(x, y)
- Moves turtle to specified x and y coordinates on the Cartesian plane.

Filling Shapes
- Methods:
- begin_fill() - Marks beginning of a shape to be filled.
- end_fill() - Marks end of the shape to be filled.
- fillcolor(color) - Sets the fill color of the shape.
- Must draw a closed shape for filling to be effective.

Getting User Input
Input Function
- num_input(title, prompt)
- Displays a dialog box prompting for numerical input.
- title: Title of the dialog box.
- prompt: Prompt shown inside the dialog box asking for input.

Using Loops to Simplify Code
- Advantages of using loops over repetitive action coding.
- For instance, to draw a square:
- Instead of writing forward and right multiple times, use a loop to repeat this sequence.
- Example:
  python for i in range(4): turtle.forward(100) turtle.right(90)

The assignment is to draw a hexagon using turtle graphics with repetition structures.
Each side of the hexagon should be 100 pixels in length.
Change the screen's background color to any preferred color.

All turtle methods follow the same dot notation pattern (turtle_name.method()).
Remember to ensure that all closures of shapes and commands are properly aligned to avoid errors in rendering.