okay... well, what don't you understand about how to make a ball?
you are using records. Well done. Let's use a record for our ball:
| code: |
var ball : record x, y, vx, vy : real radius, clr : int end record |
There's your ball.
Now, to apply gravity to it:
| code: |
var ball : record x, y, vx, vy : real radius, clr : int end record ball.x := 10 ball.y := 10 ball.vx := 3 ball.vy := 4 ball.radius := 6 ball.clr := brightblue const gravity := 0.05 setscreen ("offscreenonly") loop ball.vy -= gravity ball.x += ball.vx ball.y += ball.vy cls drawfilloval (round (ball.x), round (ball.y), ball.radius, ball.radius, ball.clr) View.Update delay (10) end loop |
Now, to make it bounce off a wall:
| code: |
if ball.x + ball.radius >= maxx or ball.x - ball.radius <= 0 then ball.vx *= -1 end if |
add that somewhere in the main loop. I suggest just before the bit involving gravity and updating the x and y pos. of the ball.
After that, you need to keep track of where the ball lands.
| code: |
if ball.y - ball.radius <= 0 then if ball.x < maxx div 2 then %ball landed on the left side. Give player 2 a point and reset the players and the ball else %ball landed on the right side. Give player 1 a point and reset the players and the ball end if end if |
add that code in somewhere in the main loop. I suggest after the previous bit about bouncing off the wall.
Next, you need to make the ball bounce off the players, which is by far the hardest thing to do. Visit my Circular Collision Data Tutorial and read up on some of compsci.ca's methods for achieving this. Pick one, or make your own, and try to get it to work.
Best of luck! I spent a long time trying to make a Slime Volleyball program. Know that it can be done.
Feel free to ask any more questions
-Cervantes
. Hover your mouse over it in one of my posts.