def draw
background(240)
v0 = createVector(0, 0)
v1 = createVector(mouseX, mouseY)
drawArrow(v0, v1, 'black')
noStroke
text(format('vector length: %.2f', P5Vector.mag(v1)), 10, 70, 90, 30)
end
# draw an arrow for a vector at a given base position
def drawArrow(base, vec, myColor)
push do
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)
end
end