def createShape(self, verticies):
assert len(verticies) >= 2
verticies = self.verticies = map(Vec2d, verticies)
if is_clockwise(verticies): # fix it if it is clockwise
average = sum(verticies) / len(verticies)
verticies.sort(key=lambda v: (average-v).get_angle())
assert not is_clockwise(verticies), 'OMG, my code is wrong! the poly points are still clockwise'
assert is_convex(verticies), 'Shape verticies must be convex!'
if len(verticies) in self.specialPolyTypes:
self.polyType = self.specialPolyTypes[len(verticies)]
else:
self.polyType = pg.GL_POLYGON
self.shape = Poly(self.body, verticies)
# note: collisionLayers and collisionType get created by physics.py
self.shape.layers = self.collisionLayers
self.shape.collision_type = self.collisionType
self.shapes = [self.shape]
bb = self.shape.cache_bb()
self.size = Vec2d(bb.right-bb.left, bb.top-bb.bottom)
def assert_valid(verts):
if len(verts) < 3:
raise TypeError('need 3 or more verts: %s' % (verts,))
if not is_convex(verts):
raise TypeError('not convex: %s' % (verts,))
if area(verts) == 0.0:
raise TypeError("colinear: %s" % (verts,))
# note: pymunk considers y-axis points down, ours points up,
# hence we consider pymunk's 'clockwise' to be anticlockwise
if not is_clockwise(verts):
raise TypeError('anticlockwise winding: %s' % (verts,))