def paint_text(self, parent_offset, surface):
mid = len(self.line.current)/2
midvalues = self.line.current[mid:mid+2]
if len(midvalues) < 2:
# not enough control points to figure out where to put text
return
midsrc, middst = midvalues
angle = ((middst - midsrc).angle() % (2*math.pi))
if 1*(2*math.pi)/4 < angle < 3*(2*math.pi)/4:
angle += math.pi
angle %= 2*math.pi
t = self.rendered_text
text_centering_vector = Point((-t.get_width()/2, -t.get_height()))
text_centering_length = text_centering_vector.norm()
text_centering_angle = text_centering_vector.angle()
rt, coors = rotate_surface(t, angle)
# coors[0] is where the original topleft is in the
# rotated surface:
topleft = coors[0]
desired_topleft = midsrc + from_polar(text_centering_angle+angle,
text_centering_length)
pos = tuple(desired_topleft - topleft + parent_offset)
surface.blit(rt, map(int, pos))
def n_point_regular_polygon(n, radius, center, phase=0):
twopi = 2*math.pi
for i in xrange(n):
angle = twopi/n*i + phase
yield from_polar(angle, radius) + center