def calculatePoints(self):
# Filter the points, first we get the undermost points, and then,
# The point which less angle from z+ vector by y+ vector has.
global epsilon
vertices = [list(p.point().position()) for p in self.prim.vertices()]
lessy = vertices[0][1]
mayPoints = []
for point in vertices:
if((point[1] - epsilon) < lessy):
mayPoints.append(point)
if(point[1] < (lessy - epsilon)):
lessy = point[1]
mayPoints = [point]
# We construct vectors from points to determine which is leftmost, so we delete 'y' component
minAngle = 2 * math.pi + epsilon
for point in mayPoints:
vec = GeoMath.vecNormalize([point[0], 0, point[2]])
angle = GeoMath.angleBetweenPointsByVec([0, 0, 1], vec, [0, 1, 0])
if(angle < minAngle):
minAngle = angle
minPoint = point
index = vertices.index(minPoint)
previousPoint = vertices[index - 1]
pointWhichIsRelative = minPoint
nextPoint = vertices[(index + 1) % len(vertices)]
self.set_previous_point(previousPoint)
self.set_point_which_is_relative(pointWhichIsRelative)
self.set_next_point(nextPoint)
