angleMode()

Changes the unit system used to measure angles.

Degrees and radians are both units for measuring angles. There are 360˚ in one full rotation. A full rotation is 2 × π (about 6.28) radians.

Functions such as rotate() and sin() expect angles measured radians by default. Calling angleMode(DEGREES) switches to degrees. Calling angleMode(RADIANS) switches back to radians.

Calling angleMode() with no arguments returns current angle mode, which is either RADIANS or DEGREES.

Examples

angleMode example 1

function setup()
  size(100, 100)

  background(200)

  -- Rotate 1/8 turn.
  rotate(QUARTER_PI)

  -- Draw a line.
  line(0, 0, 80, 0)

  describe('A diagonal line radiating from the top-left corner of a square.')
end

angleMode example 2

function setup() 
  size(100, 100)

  background(200)

  -- Use degrees.
  angleMode(DEGREES)

  -- Rotate 1/8 turn.
  rotate(45)

  -- Draw a line.
  line(0, 0, 80, 0)

  describe('A diagonal line radiating from the top-left corner of a square.')
end

angleMode example 3

function setup() 
  size(100, 100)

  background(50)

  -- Calculate the angle to rotate.
  local angle = TWO_PI / 7

  -- Move the origin to the center.
  translate(50, 50)

  -- Style the flower.
  noStroke()
  fill(255, 50)

  -- Draw the flower.
  for i = 0, 7 do
    ellipse(0, 0, 80, 20)
    rotate(angle)
  end

  describe('A translucent white flower on a dark background.')
end

angleMode example 4

function setup() 
  size(100, 100)

  background(50)

  -- Use degrees.
  angleMode(DEGREES)

  -- Calculate the angle to rotate.
  local angle = 360 / 7

  -- Move the origin to the center.
  translate(50, 50)

  -- Style the flower.
  noStroke()
  fill(255, 50)

  -- Draw the flower.
  for i = 0,7 do
    ellipse(0, 0, 80, 20)
    rotate(angle)
  end

  describe('A translucent white flower on a dark background.')
end

angleMode example 5

function setup()
  size(100, 100)

  describe('A white ball on a string oscillates left and right.')
end

function draw()
  background(200)

  -- Calculate the coordinates.
  local x = 30 * cos(frameCount * 0.05) + 50
  local y = 50

  -- Draw the oscillator.
  line(50, y, x, y)
  circle(x, y, 20)
end

angleMode example 6

function setup()
  size(100, 100)

  -- Use degrees.
  angleMode(DEGREES)

  describe('A white ball on a string oscillates left and right.')
end

function draw()
  background(200)

  -- Calculate the coordinates.
  local x = 30 * cos(frameCount * 2.86) + 50
  local y = 50

  -- Draw the oscillator.
  line(50, y, x, y)
  circle(x, y, 20)
end

angleMode example 7

function setup()
  size(100, 100)

  background(200)

  -- Draw the upper line.
  rotate(PI / 6)
  line(0, 0, 80, 0)

  -- Use degrees.
  angleMode(DEGREES)

  -- Draw the lower line.
  rotate(30)
  line(0, 0, 80, 0)

  describe('Two diagonal lines radiating from the top-left corner of a square. The lines are oriented 30 degrees from the edges of the square and 30 degrees apart from each other.')
end

Syntax

angleMode(mode)

angleMode()

Parameters

Parameter
mode	Constant: either RADIANS or DEGREES.

angleMode()

Examples

Syntax

Parameters

Related