WEBVTT 0 00:00.150 --> 00:01.080 In the last step, 1 00:01.110 --> 00:06.110 we figured out how to detect when the player turtle hits a car and to stop the 2 00:06.150 --> 00:08.850 while loop which stops the game at that point. 3 00:09.870 --> 00:14.220 Now we're going to figure out how we can detect when the turtle reaches the 4 00:14.220 --> 00:19.220 other side of the screen so that once our turtle makes a successful crossing, 5 00:20.790 --> 00:25.470 then we can return the turtle to the starting position and speed up all the 6 00:25.470 --> 00:29.490 cars. So I'm going to do that right here, 7 00:29.850 --> 00:34.080 and I'm going to detect a successful crossing. 8 00:35.040 --> 00:39.630 So what is a successful crossing? Well, the player turtle has the reach 9 00:39.810 --> 00:41.130 the finish line, right? 10 00:41.430 --> 00:46.430 Which we've defined the Y value for as 280 here in the constant. 11 00:47.850 --> 00:49.710 Now you could do this in a number of ways. 12 00:50.100 --> 00:55.100 You could define a method here or simply just get hold of the player's position 13 00:55.830 --> 01:00.480 and then figure out if it's over 280 inside our main.py. 14 01:01.200 --> 01:03.870 Now I'm going to create a method here instead 15 01:04.500 --> 01:09.060 and I'm going to call the method is_at_finish_line. 16 01:10.680 --> 01:13.050 This method is going to return true 17 01:13.380 --> 01:17.160 if the turtle is at the finish line and false while it's not. 18 01:17.760 --> 01:19.980 So how do we detect this? Well, 19 01:19.980 --> 01:23.400 we can get our self.ycor 20 01:23.940 --> 01:28.650 and we can see if that is greater than 280, 21 01:28.920 --> 01:32.010 which is our finished line Y value. 22 01:32.370 --> 01:36.090 What that means we've pretty much gone over the finish line, right? 23 01:36.510 --> 01:39.570 So if this is the case, then we're going to return true. 24 01:39.930 --> 01:43.650 But while that's not the case, any other time when we check this, 25 01:43.890 --> 01:45.540 we're going to return false. 26 01:46.170 --> 01:49.200 So now coming back to our main.py, 27 01:49.530 --> 01:54.240 we can call our player.is_at_finish_line and we can say, 28 01:54.270 --> 01:57.660 if this is true, well in that case 29 01:58.050 --> 02:01.260 we're going to get the player to go back to the starting position. 30 02:01.920 --> 02:06.660 So inside our player class let's create yet another method which I'm going to 31 02:06.660 --> 02:09.060 call go_to_start. 32 02:09.900 --> 02:14.900 And this just involves getting our player to go to the starting position 33 02:17.430 --> 02:20.190 which we've defined here in a constant. 34 02:20.820 --> 02:23.640 So notice how we've got a little bit of repetition here, 35 02:23.640 --> 02:28.640 so we can actually delete this line and simply call self. 36 02:29.010 --> 02:32.460 go_to_start. Back in our main.py 37 02:32.520 --> 02:37.230 once the player is at the finish line, we're going to get the player to go 38 02:37.230 --> 02:41.640 to the stat.r And if we go ahead and run our code 39 02:41.700 --> 02:42.930 as it is right now, 40 02:43.200 --> 02:47.550 you can see that once the turtle makes it across the road, 41 02:47.630 --> 02:52.630 [inaudible] 42 02:56.930 --> 02:59.240 it goes back to the starting position. 43 03:00.220 --> 03:05.220 Now the very last thing we need to do is to increase the speed of the cars when 44 03:06.310 --> 03:08.050 the player reaches the other side, 45 03:08.260 --> 03:11.380 because effectively they've just gone to the next level. 46 03:12.130 --> 03:17.130 What we can do is when the player reaches the finish line, 47 03:17.710 --> 03:21.970 we can get the car_manager to increase the speed of the cars. 48 03:22.420 --> 03:25.660 Let's create a method inside our CarManager class 49 03:25.690 --> 03:30.160 which we'll call level_up. And in this method, 50 03:30.280 --> 03:35.280 we're going to get the cars' speed to increase by 10 every time. 51 03:35.950 --> 03:40.950 So if we have an attribute called car_speed and we initially set it as the 52 03:43.510 --> 03:45.130 starting move distance, 53 03:45.730 --> 03:50.730 and then we use this car_speed to determine how far it should move backward 54 03:51.250 --> 03:53.950 each time. Well then when we level up, 55 03:53.980 --> 03:58.980 we can say self.car_speed now increases by the increment that we've defined 56 03:59.890 --> 04:02.560 here, which is the move increment. 57 04:03.760 --> 04:08.410 So now when our player reaches the other side at the finish line, 58 04:08.680 --> 04:11.320 then in addition to getting the player to go to the start, 59 04:11.590 --> 04:16.330 we're going to get the car_manager to level up our cars as well. 60 04:16.960 --> 04:21.010 So now when my turtle reaches the other side of the screen, 61 04:21.340 --> 04:24.550 not only does the turtle go back to the original position, 62 04:24.790 --> 04:27.280 but the cars also increase in speed.