The goal for this chapter is to look at some programming principles and see what kind of aesthetics might emerge from them.

Variables

Variables let you store and retrieve pieces of information at different points in your program.

In Javascript, you declare a variable using the keyword let, followed by name for our variable, and its initial value. If we wanted to store the number 17 in a variable called a, we would write:

let a = 17

After that, we can use a anywhere in our program, and the computer will retrieve its value from memory:

c.fillRect(10,10,a,a)

You can also set variables relative to other variables. In this case, the computer will look up the values of base and ratio, multiply them and assign the result to a.

let ratio = 1.5
let w = 10
let h = base * ratio

c.fillRect(10,10,w,h)

Loops

let i = 0;
while (i < 100){
    c.fillRect(10, i)
    i++;
}

Exercise: Variables and Loops

Let's try to put these two concepts together to make a drawing.