// System.out.println(cart.getClass().getSimpleName() + ": " + cart.entityId + " collided with " + other.getClass().getSimpleName() + ": " + other.entityId);
Vec2D cartPos = new Vec2D(cart.posX, cart.posZ);
Vec2D otherPos = new Vec2D(other.posX, other.posZ);
Vec2D unit = Vec2D.subtract(otherPos, cartPos);
unit.normalize();
double distance = cart.getDistanceToEntity(other);
double depth = distance - OPTIMAL_DISTANCE;
double forceX = 0;