def collide(self, obj):
dist = sqrt((self.pos[0]-obj.pos[0])**2 +
(self.pos[1]-obj.pos[1])**2)
d = util.vsub(obj.pos, self.pos)
par = util.vproj(self.vel, d)
orth = util.vsub(self.vel, par)
if util.vdot(self.vel, d) > 0:
self.force = util.vadd(self.force,
util.vmuls(par, -1.5 * self.mass))
overlap = max(((self.size + obj.size) - dist) / 20.0, .1)
self.force = util.vadd(self.force,
util.vmuls(d, -overlap / dist * self.mass))
def update(self):
self.force[1] += -.1 * self.mass
self.compute_wall_force_circle(self.size, .5)
# air resistance
if util.vmag(self.vel) > 1:
vmag = util.vmag(self.vel)
vdir = util.vdivs(self.vel, -.9 * vmag)
self.force = util.vadd(self.force, vdir)
self.integrate_force()
self.vel[0] = util.clamp(self.vel[0], -20, 20)
self.vel[1] = util.clamp(self.vel[1], -20, 20)
