def draw 
  background(240)
  v0 = createVector(0, 0)
  v1 = createVector(mouseX, mouseY)
  drawArrow(v0, v1, 'black')
  noStroke
  text(v1.toString, 10, 25, 90, 75)
end

def drawArrow(base, vec, myColor) 
  push
  stroke(myColor)
  strokeWeight(3)
  fill(myColor)
  translate(base.x, base.y)
  line(0, 0, vec.x, vec.y)
  rotate(vec.heading)
  arrowSize = 7
  translate(vec.mag - arrowSize, 0)
  triangle(0, arrowSize / 2, 0, -arrowSize / 2, arrowSize, 0)
  pop
end