for maryrosecook and pistol slut

bouncegrenades.py

def DetectCollision(grenade, obj):
    hgw = grenade.width / 2  # half grenade width
    hgh = grenade.height / 2
    aug_obj = Rectangle(obj.x1 - hgw, obj.y1 - hgh,
                        obj.x2 + hgw, obj.y2 + hgh)
    if aug_obj.contains(grenade.center):
        BounceGrenade(grenade, aug_obj)

def BounceGrenade(grenade, aug_obj):
    vsegs = [Segment(aug_obj.x1, aug_obj.y1, aug_obj.x1, aug_obj.y2),
             Segment(aug_obj.x2, aug_obj.y1, aug_obj.x2, aug_obj.y2)]
    hsegs = [Segment(aug_obj.x1, aug_obj.y1, aug_obj.x2, aug_obj.y1),
             Segment(aug_obj.x1, aug_obj.y2, aug_obj.x2, aug_obj.y2)]
    trajectory = Segment(grenade.last_center, grenade.center)
    for seg in vsegs:
        if trajectory.intersect(seg):
            distance_into_obj = grenade.center - seg.x1
            grenade.center -= Vector(2 * distance_into_obj, 0)
            return
    for seg in hsegs:
        if trajectory.intersect(seg):
            distance_into_obj = grenade.center - seg.y1
            grenade.center -= Vector(0, 2 * distance_into_obj)
            return