from visual import*
from visual.graph import*

bolt_pos = vector(-.1, -1, 0) #position of bolt relative to rod center
G = 6.67e-11
rod_mass = 1244.491
L = 10
rod_radius = 0.05
bites = 10 #number of dms you want
bolt_mass = 0.5
bolt_radius = 0.2
M = 10

#graphics
vscale=.1
bolt_object = sphere(pos=bolt_pos, radius=bolt_radius, color=color.blue)
rod_object = cylinder(pos=(-L,0,0), axis=(2*L,0,0), radius=rod_radius, color=color.red)
force_object = arrow(pos=bolt_pos, axis=(0,0,0), shaftwidth=0.1)

#initials
dx = (2*L)/bites
dm = (rod_mass/(bites))

#inital force to integrate from
force = vector(0,0,0)


#for m in range(-M,M):  #comment out loop that drew all the arrows
    #bolt_pos = vector(2*m, 8, 0)
initial_vel = vector(0.00001,0,-0.00001)
#point = sphere(pos=bolt_pos, radius=0.2, color=color.magenta, make_trail=true)
#force_object = arrow(pos=(bolt_pos), axis=(0,0,0), shaftwidth=0.15, color=color.cyan)

momentum = initial_vel*bolt_mass
bolt_object.pos = bolt_pos
t = 0
dt = 100


#force = vector(0,0,0)
while t < 200000:
    rate(1000000)
    t = t + dt
    force = vector(0,0,0)
    for n in range (0, bites):
        x = vector((-L + (dx/2) + (n*dx)), 0, 0)
       # print x
        r = bolt_object.pos - x

        dF = -G*((bolt_mass * dm)/(mag2(r))) * norm(r)
        force = force + dF

    momentum = momentum + force*dt
    bolt_object.pos = bolt_object.pos + (momentum/bolt_mass)*dt

   # force_object.pos = bolt_object.pos
   # force_object.axis = vscale * force/G *4
    print force
    #print momentum