Functions

Create reusable blocks of code with functions.

Creating Functions

Use fn to define a function:

fn setup() {
  size(300, 200)
}

fn draw() {
  background(rgb(30, 30, 40))

  // Call our custom function
  drawFlower(100, 100)
  drawFlower(200, 100)
}

fn drawFlower(x, y) {
  fill(pink)
  circle(x - 15, y, 15)
  circle(x + 15, y, 15)
  circle(x, y - 15, 15)
  circle(x, y + 15, 15)
  fill(yellow)
  circle(x, y, 12)
}

Parameters

Functions can take inputs (parameters) to customize behavior:

fn setup() {
  size(300, 200)
}

fn draw() {
  background(rgb(30, 30, 40))

  // Same function, different sizes and colors
  drawStar(75, 100, 30, coral)
  drawStar(150, 100, 45, cyan)
  drawStar(225, 100, 25, yellow)
}

fn drawStar(x, y, size, color) {
  fill(color)
  for i in 0..5 {
    let angle = i * 72 - 90
    let px = x + cos(radians(angle)) * size
    let py = y + sin(radians(angle)) * size
    circle(px, py, size / 3)
  }
}

Return Values

Functions can return a value with return:

fn setup() {
  size(300, 200)
}

fn draw() {
  background(rgb(30, 30, 40))

  let d = distance(50, 50, mouseX, mouseY)
  let size = map(d, 0, 300, 80, 10)

  fill(coral)
  circle(50, 50, size)

  fill(white)
  text("Distance: " + round(d), 20, 180)
}

fn distance(x1, y1, x2, y2) {
  let dx = x2 - x1
  let dy = y2 - y1
  return sqrt(dx * dx + dy * dy)
}

Built-in Math Functions

Bloom includes many useful functions:

sin(angle), cos(angle) - Trigonometry (radians)
abs(n) - Absolute value
round(n) - Round to nearest integer
floor(n), ceil(n) - Round down/up
min(a, b), max(a, b) - Smaller/larger value
sqrt(n) - Square root
random(min, max) - Random number
map(v, a, b, c, d) - Map value from one range to another
lerp(a, b, t) - Linear interpolation

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