def redraw_link(self, instance=None, value=None):
root = App.get_running_app().root
if root is not None:
root.canvas.after.remove_group(str(self.uid))
if self.linked_to_object is not None:
# find out the vectors for the keyboard (in objects (its) co-ordinates)
a = Vector(*self.center)
b = Vector(a[0], a[1]+10)
v = b-a
vup = v.rotate(self.rotation)
#vl = vup.rotate(90) # rotation is anti-clockwise
#vr = vup.rotate(-90) # rotation is anti-clockwise
vup = vup.normalize()
#vl = vl.normalize()
#vr = vr.normalize()
center = a
up_half = vup*self.size[1]/2*self.scale
#left_half = vl*self.size[0]/2*self.scale
#right_half = -left_half
# positions representing the object, have to use vectors, as otherwise pos, etc. gives back the bounding box instead
top_center = center + up_half
#top_left = center + left_half + up_half
#top_right = center + right_half + up_half
#bottom_left = center + left_half - up_half
#bottom_right = center + right_half - up_half
# figure out the vectors for the linked object (in object co-ordinates)
la = Vector(*self.linked_to_object.center)
lb = Vector(la[0], la[1]+10)
lv = lb-la
lvup = lv.rotate(self.linked_to_object.rotation)
lvl = lvup.rotate(90) # rotation is anti-clockwise
#lvr = lvup.rotate(-90) # rotation is anti-clockwise
lvup = lvup.normalize()
lvl = lvl.normalize()
#lvr = lvr.normalize()
lcenter = la
lup_half = lvup*self.linked_to_object.size[1]/2*self.linked_to_object.scale
lleft_half = lvl*self.linked_to_object.size[0]/2*self.linked_to_object.scale
lright_half = -lleft_half
# positions representing the object, have to use vectors, as otherwise pos, etc. gives back the bounding box instead
#ltop_center = lcenter + lup_half
#lbottom_center = lcenter - lup_half
#lleft_center = lcenter + lleft_half
#lright_center = lcenter + lright_half
ltop_left = lcenter + lleft_half + lup_half
ltop_right = lcenter + lright_half + lup_half
lbottom_left = lcenter + lleft_half - lup_half
lbottom_right = lcenter + lright_half - lup_half
wk_top_center = self.to_window(*top_center)
wl_center = self.linked_to_object.to_window(*lcenter)
# this is where you can do the code for the intersection testing
wl_top_left = self.linked_to_object.to_window(*ltop_left)
wl_top_right = self.linked_to_object.to_window(*ltop_right)
wl_bottom_left = self.linked_to_object.to_window(*lbottom_left)
wl_bottom_right = self.linked_to_object.to_window(*lbottom_right)
# quit when we find the first intersection, else quit when at the end
shouldDraw = False
while True:
# bottom line
intersects, collinear, position = Vector.line_segment_intersection(wk_top_center, wl_center, wl_bottom_left, wl_bottom_right)
if intersects and collinear=="not-collinear":
x2, y2 = position
shouldDraw = True
break
# top line
intersects, collinear, position = Vector.line_segment_intersection(wk_top_center, wl_center, wl_top_left, wl_top_right)
if intersects and collinear=="not-collinear":
x2, y2 = position
shouldDraw = True
break
# right side
intersects, collinear, position = Vector.line_segment_intersection(wk_top_center, wl_center, wl_bottom_right, wl_top_right)
if intersects and collinear=="not-collinear":
x2, y2 = position
shouldDraw = True
break
# left side
intersects, collinear, position = Vector.line_segment_intersection(wk_top_center, wl_center, wl_bottom_left, wl_top_left)
if intersects and collinear=="not-collinear":
x2, y2 = position
shouldDraw = True
break
# default get out of the loop
break
# only draw, if we have a point to draw to
if shouldDraw is True:
x1, y1 = wk_top_center
if self.draw_arrow_head_on_link is False:
with root.canvas.after:
Color(*self.link_colour)
# main line
Line(points=(x1, y1, x2, y2),
width=self.link_width,
group=str(self.uid))
Color(1,1,1,.1)
# main line
Line(points=(x1, y1, x2, y2),
width=self.link_width/3.0,
group=str(self.uid))
else:
_a = Vector(x1, y1)
_b = Vector(x2, y2)
_v = _b-_a
_vl = _v.rotate(140)
_vl = _vl.normalize()
_vr = _v.rotate(-140)
_vr = _vr.normalize()
end_point_left = _b+_vl*20
end_point_right = _b+_vr*20
with root.canvas.after:
Color(*self.link_colour)
# main line
Line(points=(x1, y1, x2, y2),
width=self.link_width,
group=str(self.uid))
# left end point
Line(points=(end_point_left.x, end_point_left.y, x2, y2),
width=self.link_width,
group=str(self.uid))
# right end point
Line(points=(end_point_right.x, end_point_right.y, x2, y2),
width=self.link_width,
group=str(self.uid))
Color(1,1,1,.1)
# main line
Line(points=(x1, y1, x2, y2),
width=self.link_width/3.0,
group=str(self.uid))
# left end point
Line(points=(end_point_left.x, end_point_left.y, x2, y2),
width=self.link_width/3.0,
group=str(self.uid))
# right end point
Line(points=(end_point_right.x, end_point_right.y, x2, y2),
width=self.link_width/3.0,
group=str(self.uid))
# refresh the scene, which adds the line disconnect button
self.refresh()
