SCRIPT-8

README.md

This is a SCRIPT-8 cassette. Click here to boot it.

code.js

// title: Trigo-3

/* eslint-disable no-global-assign */
initialState = {
  x: 0
}

update = state => {
  state.x += 0.01 * Math.PI
  if (state.x > Math.PI) {
    state.x = -Math.PI
  }
}

draw = state => {
  clear()

  // origin
  const o = { x: 64, y: 64 }

  // axes
  line(o.x, 0, o.x, 128, 6)
  line(0, o.y, 128, o.y, 6)

  const r = 20

  // draw sine
  range(-0.5, 0.5, 0.01).forEach(i => {
    const angle = i * 2 * Math.PI
    const x = angle
    const y = Math.sin(angle)
    rectFill(o.x + r * x, o.y + r * y, 1, 1, 4)
  })

  // draw axes marker lines
  line(
    o.x + r * state.x,
    o.y + r * Math.sin(state.x),
    o.x,
    o.y + r * Math.sin(state.x),
    1
  )
  line(
    o.x + r * state.x,
    o.y + r * Math.sin(state.x),
    o.x + r * state.x,
    o.y,
    1
  )

  // draw axes markers
  circFill(o.x + r * state.x, o.y, 2, 0)
  circFill(o.x, o.y + r * Math.sin(state.x), 2, 0)

  // draw marker
  circFill(o.x + r * state.x, o.y + r * Math.sin(state.x), 1, 7)
  circStroke(o.x + r * state.x, o.y + r * Math.sin(state.x), 2, 0)

  print(0, 0, 'sine', 0)
}