def test_get_mass(self):
chunk = Chunk()
self.assertEquals(chunk.get_mass(), 0.0, "bad initial mass")
shard1 = Disc(gold, 5)
shard2 = Block(gold, self.unitsquare)
chunk.shards = [shard1, shard2]
self.assertEquals(chunk.get_mass(), (25 * pi + 1) * gold.density,
"bad mass")
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_set_shards_disc(self):
radius = 4
offset = (3, 2)
disc = Disc(gold, radius, offset)
chunk = Chunk()
chunk.set_shards(disc)
self.assertEquals(chunk.shards, (disc,), "bad shards")
shard = chunk.shards[0]
self.assertEquals(shard.get_centroid(), (0, 0))
def test_position_read_from_body(self):
chunk = Chunk()
self.assertNone(chunk.position, "bad initial position")
self.assertNone(chunk.angle, "bad initial angle")
space = Space()
chunk.add_to_space(space, (11, 22), 0.456)
self.assertEquals(chunk.position, Vec2d(11, 22), "bad position")
self.assertAlmostEquals(chunk.angle, 0.456, places=7,
msg="bad angle")
def test_add_chunk(self):
world = World()
chunk = Chunk(Disc(Material.gold, 1))
chunk.add_to_space = Listener()
world.add_chunk(chunk, (1, 2), 0.5)
self.assertEquals(world.chunks, set([chunk]), "chunk not added")
self.assertEquals(
chunk.add_to_space.args,
(world.space, (1, 2), 0.5),
"chunk not added to space")
def test_offset_shards(self):
chunk = Chunk()
shard1 = Disc(gold, 5, (10, 20))
shard2 = Block(gold, self.unitsquare, (30, 40), center=True)
chunk.shards = [shard1, shard2]
chunk._offset_shards((+2, -3))
offset1 = chunk.shards[0].get_centroid()
self.assertEquals(offset1, (12, 17), "bad shard1 offset")
offset2 = chunk.shards[1].get_centroid()
self.assertEquals(offset2, (32, 37), "bad shard2 offset")
def test_set_shards_block(self):
verts = [(0, 0), (0, 1), (1, 1), (1, 0)]
offset = (10, 20)
block = Block(gold, verts, offset)
self.assertEquals(block.get_centroid(), (10.5, 20.5), "bad offset")
chunk = Chunk()
chunk.set_shards(block)
self.assertEquals(chunk.shards, (block,), "bad shards")
shard = chunk.shards[0]
self.assertEquals(shard.get_centroid(), (0, 0), "bad offset")
def test_set_shards_two_discs(self):
disc1 = Disc(gold, 4, (+100, +200))
disc2 = Disc(gold, 2, (+115, +225))
chunk = Chunk()
chunk.set_shards(disc1, disc2)
self.assertEquals(chunk.shards, (disc1, disc2), "bad shards")
shard1offset = chunk.shards[0].get_centroid()
self.assertAlmostEquals(shard1offset[0], -3.0, msg="bad offset1 x")
self.assertAlmostEquals(shard1offset[1], -5.0, msg="bad offset1 y")
shard2offset = chunk.shards[1].get_centroid()
self.assertAlmostEquals(shard2offset[0], +12.0, msg="bad offset2 x")
self.assertAlmostEquals(shard2offset[1], +20.0, msg="bad offset2 y")
def test_add_to_space_discs(self):
disc1 = Disc(gold, 1)
disc2 = Disc(gold, 2)
disc3 = Disc(gold, 3)
space = Space()
chunk = Chunk(disc1, disc2, disc3)
chunk.add_to_space(space, (1, 2), 0.75)
self.assertEquals(type(chunk.body), Body, "didnt create body")
self.assertEquals(chunk.body.position, Vec2d(1, 2), "bad position")
self.assertEquals(chunk.body.angle, 0.75, "bad angle")
self.assertEquals(space.bodies, set([chunk.body]),
"body not added to space")
self.assertEquals(len(space.shapes), 3, "shapes not added to space")
radii = set()
for circle in space.shapes:
self.assertEquals(circle.body, chunk.body, "bad Circle body")
self.assertEquals(circle.friction, 0.5, "bad friction")
self.assertEquals(circle.elasticity, 0.5, "bad elasticity")
radii.add(circle.radius)
self.assertEquals(radii, set([1, 2, 3]), "bad radii")
def DONTtest_add_to_space_blocks(self):
verts1 = [(0, 0), (0, 12), (12, 12), (12, 0)]
block1 = Block(gold, verts1, (0, +12))
verts2 = [(0, 0), (0, 12), (24, 12), (24, 0)]
block2 = Block(gold, verts2)
chunk = Chunk(block1, block2)
space = Space()
chunk.add_to_space((100, 200), 0)
self.assertEquals(chunk.shards, (block1, block2,), "shards not added")
poly1 = chunk.shards[0].shard.get_points()
expected = [
Vec2d(92, 104), Vec2d(92, 116),
Vec2d(104, 116), Vec2d(104, 104)]
self.assertEquals(poly1, expected, "bad poly1 verts")
poly2 = chunk.shards[1].shard.get_points()
expected = [
Vec2d(92, 92), Vec2d(92, 104),
Vec2d(116, 104), Vec2d(116, 92),
]
self.assertEquals(poly2, expected, "bad poly2 verts")
def test_center_of_gravity(self):
chunk = Chunk()
self.assertEquals(chunk._center_of_gravity(), (0, 0), "bad COG0")
shard1 = Disc(gold, 2, (10, 20))
chunk = Chunk()
chunk.shards = (shard1,)
cog = chunk._center_of_gravity()
self.assertAlmostEquals(cog[0], 10, msg="bad COG1 x")
self.assertAlmostEquals(cog[1], 20, msg="bad COG1 y")
verts = [(99, 49), (99, 51), (101, 51), (101, 49)]
shard2 = Block(gold, verts)
chunk.shards = (shard2,)
self.assertEquals(chunk._center_of_gravity(), (100, 50), "bad COG2")
chunk.shards = (shard1, shard2)
totalMass = shard1.mass + shard2.mass
x = (10 * shard1.mass + 100 * shard2.mass) / totalMass
y = (20 * shard1.mass + 50 * shard2.mass) / totalMass
self.assertEquals(chunk._center_of_gravity(), (x, y), "bad COG3")