Using Pinwheel to Make Polygon

On this page, you will use your existing pinwheel block to make asterisk and polygon blocks.
Animation cycle from Asterisk to Polygon

You can use your general-purpose pinwheel procedure to create other, simpler special-purpose procedures that each do a particular job.

Asterisk with 12 branches
  1. If it isn't open already, open your U1L3-Pinwheel project from the previous page.
  2. Use your pinwheel block to create a more specialized asterisk block.
    1. First, make a new block called asterisk with two inputs: one for the number of branches and one for the length of each branch. You may wish to review how to make a new block at Unit 1 Lab 2 Page 4: Making Your Own Block. asterisk, branches:(branches) branch length:(length){pinwheel, branches: ( ) size:( ) backup:( )}
    2. Now fill in the three inputs to pinwheel so that it correctly draws an asterisk.
    Pair Programming Swap
  3. Similarly, write a polygon block that uses pinwheel with appropriate inputs to draw a polygon with a given number of sides and side length.

Debugging with pause all

You can use pause all to place breaks in your code so you can see what's happening along the way. When you run code with pause all in it, you can click the yellow Run/Pause button next to the Green Flag (play button/pause button) to move through the code up until a pause all block is reached again. The pause all block will pause every script that is running until the yellow Run/Pause button is clicked.

  1. If you look inside of pinwheel and see how you're using it in polygon, you'll see that there are steps that you don't really need for the case of a polygon. Write another version of polygon built directly out of primitive blocks (move, turn and so on). How simple can you make it?
    AAP-3.B.7
    As long as your polygon block draws the right picture, it doesn't matter to the rest of the project what's inside it.
    Save your work
  1. Use your pinwheel block code one last time to create a circle block that accepts one input for the size.
  2. Use the random block together with set pen color and set pen size to draw a variety of shapes.
    assortment of pinwheels
  1. AAP-3.B.5
    Which statement best illustrates the importance of using parameters in programming procedures (such as number of branches in the pinwheel code)?
    Parameters restrict the flexibility of procedures, making them applicable to only specific input values.
    Parameters make procedures harder to understand for beginners and should be avoided whenever possible.
    Parameters enable procedures to be generalized, allowing them to be reused with various input values (arguments).
    Parameters can be omitted without affecting the functionality of a procedure.
  1. Challenge: Create a script that draws a blue square of size 100 and then draws a red circle that fits perfectly inside it.
    red circle in blue square