We are going to build on top of the Lesson 11 code, but you still might want to save it as a new program:

> save NEWNAME.lua
cart NEWNAME.lua saved!

In the SETUP portion let's add two variables: a player score and a shark score. We are going to set them to 0 to begin with.

pscore = 0            -- Player score
sscore = 0            -- Shark  score

Let's also print the scores to the screen. We could either keep it at a fixed location like at the top of the screen…:

-- Draw
cls(11)
spr(0,px,py)          -- Player
spr(1,bx,by)          -- Bubble
spr(2,sx,sy)          -- Shark
print(pscore,5,5)
print(sscore,220,5)

Or put the score above the player and shark, so it follows them around as they move:

-- Draw
cls(11)
spr(0,px,py)          -- Player
spr(1,bx,by)          -- Bubble
spr(2,sx,sy)          -- Shark
print(pscore,px,py-8)
print(sscore,sx,sy-8)

Now let's bring in the Distance function again. Remember that this has to go at the very top of the program before everything else!

function getDistance( x1, y1, x2, y2 )
  return math.sqrt( ( x2 - x1 )^2 + ( y2 - y1 )^2 )
end

The 0.5 is the speed of the shark. Use a larger number to make it faster, or a smaller number to make it go slower.

Now the shark moves around on its own chasing the bubble. Perhaps we could make a game where both objects are chasing the bubble…? Hmmm…….

Make sure to press the CTRL+S key, or press ESC to go to the prompt and type save to save your work! If you want to access the folder with your code, type folder.

If you have a USB flash drive, make sure to copy your file over so you don't lose it when the computer resets!

⬅️ Once you're all done, go back to the course homepage!