import sys, time, math
from pyglet.gl import *
from euclid import *

window = pyglet.window.Window(512,512)

quadric = gluNewQuadric()

GRAV_CONSTANT = 1

class Planet:
    def __init__(self, pos=Vector3(0,0,0), vel=Vector3(0,0,0), mass=1.0, color=[1,1,1]):
        self.pos = pos
        self.vel = vel
        self.mass = mass
        self.color = color
    def draw(self):
        glColor3f(self.color[0], self.color[1], self.color[2])
        glPushMatrix()
        glTranslatef(self.pos[0], self.pos[1], self.pos[2])
        gluDisk(quadric, 0, 1.0, 16, 1)
        glPopMatrix()
    def update(self, dt, planets):
        force = Vector3(0, 0, 0)
        for p in planets:
            if p != self:
                d = p.pos - self.pos
                f = GRAV_CONSTANT * self.mass * p.mass / d.magnitude_squared()
                dir = d.normalized()
                force += dir * f
        acc = force / self.mass
        self.vel += acc * dt
        self.pos += self.vel * dt

planets = []
planets.append(Planet(mass=10000, color=[1,1,0]))
planets.append(Planet(pos=Vector3(10,0,0), vel=Vector3(0,28,0), mass=100.0, color=[0,1,0]))
planets.append(Planet(pos=Vector3(-14,0,0), vel=Vector3(0,-24,0), mass=50.0, color=[0,1,1]))
planets.append(Planet(pos=Vector3(0,-16,0), vel=Vector3(-30,0,0), mass=2.0, color=[1,1,1]))

@window.event
def on_draw():
    glClear(GL_COLOR_BUFFER_BIT)
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    glOrtho(-25,25, -25,25, -25,25)
    glMatrixMode(GL_MODELVIEW)

    for p in planets: p.draw()

def update(dt):
    for p in planets:
        p.update(dt, planets)

pyglet.clock.schedule_interval(update,1/60.0)
pyglet.app.run()