def accelerate(self, n):
force = (0.0, 0.0)
# attraction
for m in n.adj:
if n == m:
continue
delta = vec.sub(n.pos, m.pos)
force = vec.sub(force, vec.mul(delta, ATTRACTION))
# repulsion
for m in self.nodes:
if n == m:
continue
delta = vec.sub(n.pos, m.pos)
dist = vec.norm(delta)
if dist <= KICK_DIST and id(n) < id(m):
angle = random.uniform(0, 2 * math.pi)
kick = vec.rotate2d((KICK_SIZE, 0), angle)
n.vel = vec.add(n.vel, kick)
m.vel = vec.sub(m.vel, kick)
dist = max(dist, MIN_CLOSENESS)
delta = vec.mul(delta, REPULSION / (dist ** 3))
force = vec.add(force, delta)
n.force = force
def draw_edge(self, n, m, thickness, colour):
z1 = self.project(n.pos)
z2 = self.project(m.pos)
if thickness <= 1:
pygame.draw.aaline(self.screen, colour, z1, z2, 1)
else:
angle = math.atan2(z2[1] - z1[1], z2[0] - z1[0])
delta = vec.rotate2d((thickness / 2.0, 0), angle)
delta = (-delta[0], delta[1])
p1 = vec.add(z1, delta)
p2 = vec.sub(z1, delta)
p3 = vec.sub(z2, delta)
p4 = vec.add(z2, delta)
pygame.gfxdraw.aapolygon(self.screen, (p1, p2, p3, p4), colour)
pygame.gfxdraw.filled_polygon(self.screen, (p1, p2, p3, p4),
colour)
def mouse_moved(self, event):
if not self.mouse_down:
return
mouse_pos = pygame.mouse.get_pos()
if self.selected_node == None:
mouse_pos = vec.mul(mouse_pos, self.viewport.scale)
self.viewport.pos = vec.sub(self.pan_grab_pos, mouse_pos)
else:
self.selected_node.pos = self.unproject(mouse_pos)
def find_node_at(self, pos):
self.lock.acquire()
try:
for n in self.graph.nodes:
if vec.norm(vec.sub(
n.pos,
pos)) <= n.style.value.radius * self.viewport.scale:
return n
return None
finally:
self.lock.release()
def project(self, v):
viewport_pos = vec.sub(v, self.viewport.pos)
return vec.int_round(vec.mul(viewport_pos, 1.0 / self.viewport.scale))