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Now in the last lesson we created these rectangular cars randomly along the Y-

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axis.

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And then we managed to get them to move across to the left side of the screen.

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The next step is to detect when the turtle collides with the car.

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So that way, when the turtle hits one of the cars,

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we can stop the game and prevent further cars from moving. Inside our while

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loop I'm going to detect the collision with the car here.

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So I'm going to get hold of all the cars in the car_manager object and I'm

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going to use a for loop to loop through each of the cars in that list of cars.

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And then we're going to detect whether if the car has a distance to the player

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object that is less than 20.

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Remember that our cars are 20 pixels in height by 40 pixels in width.

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If the player is less than 20 pixels from the center of the car,

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then it probably means that it's collided with the car.

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So if this distance is less than 20,

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then we're going to stop the game.

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And the way that we stopped the game is of course,

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by turning this game_is_on from true to false.

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Let's run our code again and let's see this in action. So we can move our turtle,

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we've got randomly generated cars moving across and let's just park our turtle right

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here. When that car hit our turtle

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it immediately stopped the game. Now,

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if we want to take a look at what's happening

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so for the screen to stay open instead of closing

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once the process is finished, we can tell it to exitonclick.

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So now let's run our code again and notice this time

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if we collide with one of the cars

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you can see that it stops and it waits for further instruction,

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which eventually is going to be just the game over text showing up on screen

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and we also the final level showing up on screen. That's it.

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That's how we detect collision between the car and our player.