class Universe(object):
def __init__(self):
self.sky = SurroundingSky()
sun = Sun((0, 0, 0), (0, 0, 0))
earth = Earth(sun.offset(79262956, -128906582, -13927363), (24.85, 15.34, 2.499))
# Some interesting values:
# Distant orbit
#self.userSpaceship = UserSpaceship(earth.offset(0, 0, 19999), earth.relativeVelocity(-4.4667, 0, 0))
# Roughly as high as the ISS
self.userSpaceship = UserSpaceship(earth.offset(0, 0, earth.radius + 340), earth.relativeVelocity(-7.73, 0, 0))
# GEO
# self.userSpaceship = UserSpaceship(earth.offset(0, 0, 42164), earth.relativeVelocity(-3.07, 0, 0))
# Here's a good resource for finding velocity for a circular orbit at a given altitude,
# though you need to remember that it's altitude and not distance from the centre of the
# Earth: <http://home.att.net/~ntdoug/UCM2.html>
spaceStation = SpaceStation(earth.offset(1, 1, earth.radius + 335), earth.relativeVelocity(-7.73, 0, 0))
self.objects = []
self.objects.append(sun)
self.objects.append(earth)
self.objects.append(self.userSpaceship)
self.objects.append(spaceStation)
self.initialDashboardRelativeTo = earth
def draw(self):
# Draw the sky separately...
if self.sky:
self.sky.draw()
# In a normal OpenGL scene, we'd now do something like this:
# glTranslatef(-cX, -cY, -cZ)
# and then tell all of our objects to draw themselves at their
# world location. However, this leads to weird jiggling effects
# because of rounding. For example, if the universe has the Sun
# at (0, 0, 0) and then the user's spaceship is at (0, 0, 93000000)
# and all objects are posistioned with a fixed number of significant
# figures, then the Sun is positioned precisely in the right place
# but the spaceship might be misplaced by a meter or so -- so it
# starts jiggling around. It's better to have objects that are
# close to the camera close to the origin so that nearby objects
# are positioned accurately, and distant ones can be out.
cX, cY, cZ = self.userSpaceship.location
for obj in self.objects:
obj.positionAndDraw(-cX, -cY, -cZ)
def accelerateAndMove(self, time):
for objectToMove in self.objects:
objectToMove.accelerateAndMove(self.objects, time)
def __init__(self):
self.sky = SurroundingSky()
sun = Sun((0, 0, 0), (0, 0, 0))
earth = Earth(sun.offset(79262956, -128906582, -13927363), (24.85, 15.34, 2.499))
# Some interesting values:
# Distant orbit
#self.userSpaceship = UserSpaceship(earth.offset(0, 0, 19999), earth.relativeVelocity(-4.4667, 0, 0))
# Roughly as high as the ISS
self.userSpaceship = UserSpaceship(earth.offset(0, 0, earth.radius + 340), earth.relativeVelocity(-7.73, 0, 0))
# GEO
# self.userSpaceship = UserSpaceship(earth.offset(0, 0, 42164), earth.relativeVelocity(-3.07, 0, 0))
# Here's a good resource for finding velocity for a circular orbit at a given altitude,
# though you need to remember that it's altitude and not distance from the centre of the
# Earth: <http://home.att.net/~ntdoug/UCM2.html>
spaceStation = SpaceStation(earth.offset(1, 1, earth.radius + 335), earth.relativeVelocity(-7.73, 0, 0))
self.objects = []
self.objects.append(sun)
self.objects.append(earth)
self.objects.append(self.userSpaceship)
self.objects.append(spaceStation)
self.initialDashboardRelativeTo = earth
