def generateNeighborDict(self, time):
"""Generate dict of neighbors. A neighbor is any object
within the bounding box of an objects trajectory during time.
Objects must be able to collide to be considered neighbors"""
#first, calculate bounding box for each object
boundDict = {}
for i in range(len(self.objectList)):
p1 = self.objectList[i].pos
p2 = self.objectList[i].getPosInTime(time)
shape = self.objectList[i].shape
#Get bounding boxes at the 2 positions
box1 = shape.getBoundingBox().translate(p1)
box2 = shape.getBoundingBox().translate(p2)
#generate the union between them and store it
bbox = Rect.union(box1, box2)
boundDict[i] = bbox
d = {}
#TODO: improve, this is O(n^2) for testing
#TODO: is this only necessary for objects that can stop each other?
for i in range(len(self.objectList)):
iObj = self.objectList[i]
iRect = boundDict[i]
#Check nearby tiles
tl = [int(floor(iRect.x1/32)), int(floor(iRect.y1/32))] #top left tile indices
br = [int(ceil(iRect.x2/32)), int(ceil(iRect.y2/32))] #bottom right tile indices
for x in range(tl[0], br[0]+1):
for y in range(tl[1], br[1]+1):
jObj = self.tileGrid[x][y]
#Following Code copied from below
#this is only applicable for objects which can create
# collision events
if not CollisionFilter.canCollide(iObj,jObj):
continue
#iRect = boundDict[i]
jRect = jObj.shape.getBoundingBox().translate(jObj.pos)
if Rect.touches(iRect, jRect):
if iObj in d:
d[iObj].add(jObj)
else:
d[iObj] = set([jObj])
if jObj in d:
d[jObj].add(iObj)
else:
d[jObj] = set([iObj])
#End of copied code
#Check other objects
for j in range(i+1, len(self.objectList)):
#iObj = self.objectList[i]
jObj = self.objectList[j]
#this is only applicable for objects which can create
# collision events
if not CollisionFilter.canCollide(iObj,jObj):
continue
#iRect = boundDict[i]
jRect = boundDict[j]
if Rect.touches(iRect, jRect):
if iObj in d:
d[iObj].add(jObj)
else:
d[iObj] = set([jObj])
if jObj in d:
d[jObj].add(iObj)
else:
d[jObj] = set([iObj])
return d
