## Model 2: Projectile Motion
## Author: M. Haley
from __future__ import division
from visual import *

## CONSTANTS
g = 9.8 ## gravitational acceleration on Earth

## OBJECTS AND INITIAL VALUES
track = box(pos=vector(0,-.05,0), size=(2.0,0.05,.10), color=color.white)
cart = box(pos=vector(-1,0,0), size=(.1,.04,.06), color=color.green)
cart.m = 1
## Initialize with initial speed and angle
v0 = 5
theta = radians(0) ## argument in degrees
## components of initial velocity
v0x = v0*cos(theta)
v0y = v0*sin(theta) 
v0z = 0
## Define initial cart momentum using mass and velocity
#cart.p = 
print 'initial cart momentum =', cart.p
## create object that draws a trail behind cart
trail = curve(color=cart.color)
## Define the initial time and time step size
deltat = .01
t = 0

## CALCULATIONS
#while t < 10:
#    print 'the time is now', t
#    Fnet = vector(0,0,0)
#    ## momentum update
#    #cart.p =
#    ## position update
#    #cart.pos = 
#    ## update trail
#    trail.append(pos=cart.pos)
#    ## advance time
#    t = t + deltat
#    rate(100)
#print 'After the loop. The final time is', t