def test_get_moment(self):
chunk = Chunk()
self.assertEquals(chunk.get_moment(), 0.0, "bad initial moment")
shard1 = Disc(gold, 2, (10, 20))
shard2 = Block(gold, self.unitsquare, (100, 200))
chunk.shards = [shard1, shard2]
expected = shard1.get_moment() + shard2.get_moment()
self.assertEquals(chunk.get_moment(), expected, "bad moment")
def test_add_to_body(self):
disc = Disc(gold, 5, (1, 2))
body = Body(0, 0)
space = Space()
space.add(body)
disc.add_to_body(space, body)
self.assertNotNone(disc.shape, "didnt create shape")
self.assertEquals(disc.shape.body, body, "didnt add shape to body")
self.assertEquals(disc.shape.radius, 5.0, "bad radius")
self.assertEquals(disc.shape.center, Vec2d(1.0, 2.0), "bad center")
self.assertAlmostEquals(disc.shape.friction, gold.friction,
msg="bad friction")
self.assertAlmostEquals(disc.shape.elasticity, gold.elasticity,
msg="bad elasticity")
self.assertEquals(space.shapes, [disc.shape],
"didn't add shape to space")
def test_offset(self):
disc = Disc(gold, 10, (11, 22))
disc.offset((100, 200))
self.assertEquals(disc.get_centroid(), (111, 222), "didnt apply offset")
def test_get_centroid(self):
disc = Disc(gold, 10, (111, 222))
self.assertEquals(disc.get_centroid(), (111, 222), "bad offset")
def test_get_moment(self):
radius = 5
offset = (1, 2)
disc = Disc(gold, radius, offset)
expected = moment_for_circle(disc.mass, 0, radius, offset)
self.assertEquals(disc.get_moment(), expected, "bad moment")