from visual import *
from time import clock
from random import random
from math import *

# Stars interacting gravitationally
# Program uses Numeric Python arrays for high speed computations

win=500

############################################################
# Set up the values
############################################################
# Gravitation.  Only works vertically!
g = 9.81
# Latitude at which this is taking place in degrees
lat = 24
# Muzzle speed of the projectile in m/s
speed = 80
# Angle of elevation of gun above Earth's surface
angle = 45
# Angular velocity of the Earth in rad/s
omega = 0.05
# Distance of gun from target in metres
distance = 600


############################################################
# Do not edit below this line                              #
############################################################

# convert angles from degrees to radians
angle = (angle/360.)*2*pi
lat = (lat/360.)*2*pi
velocity = vector(0, speed * sin(angle), -speed * cos(angle))

# Define axis length and some other stuff...
L = distance + 50

print """
Right button drag to rotate view.
Left button drag up or down to move in or out.
"""

scene = display(title="Coriolis Force on a projectile", width=win, height=win,
                range=L, forward=(-1,-1,-1))

xaxis = curve(pos=[(0,0,0), (L,0,0)], color=(1.5,0.5,0.5))
yaxis = curve(pos=[(0,0,0), (0,L,0)], color=(0.5,1.5,0.5))
zaxis = curve(pos=[(0,0,0), (0,0,L)], color=(0.5,0.5,0.5))

# Put in the grass at the bottom
mybox = box(pos=(0,0,0), length=distance+100, height=1, width=distance+100, color=color.green)
##
target = sphere(pos=(0,0,0), radius=10, color=color.red)
ball = sphere(pos=(0,0,distance), radius=10, color=color.blue)
ball.trail = curve(pos=[ball.pos], color=color.yellow, radius=1)
ball.velocity = velocity
t = 0
#dt = 0.01
while 1:
    rate(200)
    """ For normal motion use the following:
    ball.pos = ball.pos + ball.velocity*dt
    ball.trail.append(pos=ball.pos)
    ball.velocity = ball.velocity + g*dt
########################################
    t = dt
    ball.pos.x = ball.pos.x + (1/3.) * omega * 9.81 * pow(t,3) * cos(lat) - (omega * ball.velocity.x * pow(t,2) * (cos(lat)-sin(lat)))/sqrt(2)
    print ball.pos.x
    ball.pos.y = ball.pos.y + (ball.velocity.y * t)/sqrt(2) - 0.5 * 9.81 * pow(t,2)
    ball.pos.z = ball.pos.z + (ball.velocity.z * t)/sqrt(2)
    ball.trail.append(pos=ball.pos)
    """

    t = t + 0.005
    ball.pos.x = (1/3.) * omega * g * pow(t,3) * cos(lat) - (omega * speed * pow(t,2) * (cos(lat)-sin(lat)))/sqrt(2)
    #print ball.pos.x
    ball.pos.y = (speed * t)/sqrt(2) - 0.5 * g * pow(t,2)
    ball.pos.z = distance + (-speed * t)/sqrt(2)
    ball.trail.append(pos=ball.pos)
    #ball.velocity = ball.velocity + g*dt    
    if (ball.y <= 0):
        print "Landed at (%f, %f, %f)" % (ball.pos.x, ball.pos.y, ball.pos.z)
        break