def test_diff(self):
x1, y1 = 42, 24
x2, y2 = 0.1, -0.3
a = Point(x1, y1)
b = Point(x2, y2)
self.assertEqual((x1 - x2, y1 - y2), a - b)
def test_sum(self):
x1, y1 = 42, 24
x2, y2 = 0.1, -0.3
a = Point(x1, y1)
b = Point(x2, y2)
self.assertEqual((x1 + x2, y1 + y2), a + b)
def reset(self):
super(SpringLayout, self).reset()
# set random initial positions
for vertex in range(len(self._graph.vertices)):
self.set_unlocked_location(
vertex,
Point(self.size.x * random.random(),
self.size.y * random.random()))
self._velocities = dict.fromkeys(
list(range(len(self._graph.vertices))), Point())
def _on_drag(self, event):
if self._click is not None:
if self._click_id is not None:
picked = self._picked_state.get_picked()
if picked:
for vertex in picked:
self._canvas.move_vertex(vertex,
Point(event.x, event.y) - self._click)
self._click = Point(event.x, event.y)
else:
x0, x1 = graph.ordered_pair(self._selection.x, event.x)
y0, y1 = graph.ordered_pair(self._selection.y, event.y)
self._canvas.coords(self._selection_rect, x0, y0, x1, y1)
def step(self, time_step=0.2):
"""Calculates position of vertices after a lapse of `time_step' after
last position.
"""
for vertex in range(len(self._graph.vertices)):
force = Point()
# repulsion between vertices
for other in range(len(self._graph.vertices)):
if other == vertex: continue
force += self._repulsion_force(vertex, other)
# attraction between edges' ends
for other in self._graph.neighbors(vertex):
force += self._attraction_force(vertex, other)
# border contact force
def transform_force(coord, right_border, f):
if coord == 0:
return max(0, f)
if coord == right_border:
return min(0, f)
return f
force = Point(
transform_force(self[vertex].x, self.size.x, force.x),
transform_force(self[vertex].y, self.size.y, force.y))
vel = self._damping * (self._velocities[vertex] +
time_step * force)
vel = Point(transform_force(self[vertex].x, self.size.x, vel.x),
transform_force(self[vertex].y, self.size.y, vel.y))
# here we constrain maximal speed
step_distance_x = math.fabs(vel.x) * time_step
if step_distance_x > self.size.x * 0.1:
vel *= 0.1 * self.size.x / step_distance_x
step_distance_y = math.fabs(vel.y) * time_step
if step_distance_y > self.size.y * 0.1:
vel *= 0.1 * self.size.x / step_distance_y
self._velocities[vertex] = vel
# this is to prevent going behind borders:
fx = lambda a: min(max(0, a), self.size.x)
fy = lambda b: min(max(0, b), self.size.y)
p = self[vertex] + time_step * vel # next position of vertex
self.set_unlocked_location(vertex, Point(fx(p.x), fy(p.y)))
def move_vertex(self, vertex, v):
"""Move `vertex' by vector `v'
"""
id = vertex.shape.id
self.move(id, v.x, v.y)
canvas_location = self._get_shape_center(id)
layout_location = self._convert_canvas_location(canvas_location)
self._layout[self.graph.index(vertex.value)] = layout_location
self._update_vertex_label_location(vertex)
# move edges ends
for edge in vertex.incident:
if vertex is edge.start:
self._move_edge(edge, v, Point())
else:
self._move_edge(edge, Point(), v)
def test_setLocation(self):
self.assertEquals((0.42, 0.42), self.layout[0])
self.layout[1] = Point(1, 1)
self.assertEquals((1, 1), self.layout[1])
self.layout.reset()
self.assertEquals((0.42, 0.42), self.layout[1])
def __getitem__(self, vertex):
if vertex not in self.__locations:
self.set_unlocked_location(
vertex,
Point(self.size.x * random.random(),
self.size.y * random.random()))
return self.__locations[vertex]
def reset(self):
super(CircleLayout, self).reset()
step = 2 * math.pi / len(self.graph.vertices)
r = self._radius
for i in range(len(self._graph.vertices)):
v = Point(math.sin(step * i), math.cos(step * i))
self.set_unlocked_location(i, self._center + r * v)
def test_mult(self):
x, y = 4.2, 2.4
a = Point(x, y)
c = 10
self.assertEqual((float(x) * c, float(y) * c), a * c)
self.assertEqual((float(x) * c, float(y) * c), c * a)
def _on_configure(self):
"""Updates layout space size so that it fits the canvas. Called on
every change of canvas size.
"""
self._layout.size = Point(self.winfo_width() - 2 * self.__margin,
self.winfo_height() - 2 * self.__margin)
if self._caption:
self.coords(self._caption, 10, self.winfo_height() - 10)
def _on_press(self, event):
self._click = Point(event.x, event.y)
self._click_id = None
id = self._canvas.get_object_id_by_location(self._click)
if self._canvas.is_vertex(id):
self._click_id = id
vertex = self._canvas._get_vertex_by_shape_id(id)
if (not self._picked_state.is_picked(vertex)
and not event.state & 1):
self._picked_state.clear()
self._picked_state.pick(vertex)
else:
if not event.state & 1:
self._picked_state.clear()
self._selection = Point(event.x, event.y)
self._selection_rect = self._canvas.create_rectangle(
event.x, event.y, event.x, event.y, **SELECTION_KW)
def get_label_vector(self, vertex):
"""Returns identity vector locating the side of vertex where the
density of edges is the least.
"""
default = Point(0, 1)
edgeVec = lambda neighbor: (self[vertex] - self[neighbor]).identity()
return reduce(lambda x, y: x + y,
list(map(edgeVec, self._graph.neighbors(vertex))),
default).identity()
def __init__(self, canvas, radius, location=Point(), **kw):
super(CircleShape, self).__init__(canvas)
r = radius
self._radius = radius
x, y = location.x, location.y
self._id = canvas.create_oval(x - r,
y - r,
x + r,
y + r,
fill="white",
**kw)
def test_square(self):
a = Point(4, 5)
self.assertEqual(a.x * a.x + a.y * a.y, a.square())
def __init__(self, graph, default_location=Point(), width=400, height=400):
self.size = Point(width, height)
self._locked = set()
self._graph = graph
self.__locations = dict()
self._defaultLocation = default_location
def test_neg(self):
x, y = 1, 2
a = Point(x, y)
self.assertEqual((-x, -y), -a)
def _attraction_force(self, vertex, other):
r = (self[vertex] - self[other]).square()**0.5
if r == 0.0:
return Point()
c = 10 * self._spring_rate * (self._spring_length - r) / r
return (self[vertex] - self[other]) * c
def _repulsion_force(self, vertex, other):
r = (self[vertex] - self[other]).square()
if r == 0.0:
return Point() #random(), random())
c = 10**6 * self._electric_rate / (r**1.5)
return (self[vertex] - self[other]) * c
def test_scalar_product(self):
a = Point(2, 3)
b = Point(0.1, 0.2)
self.assertEqual(a.x * b.x + a.y * b.y, a * b)
def test_div(self):
x, y = 3, 4
a = Point(x, y)
c = 2
self.assertEqual((float(x) / c, float(y) / c), a / c)
def __init__(self, graph, r, center=(50, 50), **kw):
super(CircleLayout, self).__init__(graph, **kw)
self._center = Point(*center)
self._radius = r
self.reset()
def test_square(self):
a = Point(4, 5)
self.assertEqual(a.x * a.x + a.y * a.y, a.square())
def _convert_canvas_location(self, location):
"""Converts canvas coordinates to layout coordinates
"""
x, y = location
margin = self.__margin
return Point(x - margin, y - margin)
def _convert_layout_location(self, location):
"""Converts layout coordinates to canvas coordinates
"""
margin = self.__margin
return Point(margin + location.x, margin + location.y)
def _get_shape_center(self, id):
x, y, x1, y1 = self.coords(id)
return (Point(x, y) + Point(x1, y1)) / 2
def _get_shape_radius(self, id):
x, y, x1, y1 = self.bbox(id)
return (Point(x1, y1) - Point(x, y)).square()**0.5 / 2
def _update_layout_size(self):
"""Updates layout space size so that it fits the canvas. Called on
every change of canvas size.
"""
self._layout.size = Point(self.winfo_width() - 2 * self.__margin,
self.winfo_height() - 2 * self.__margin)
