Moving two balls at once

[SunsFan13]

Hello there, I've been fighting with this for sometime now, and I've got no idea where I've gone wrong..
Basically, I'm only able to move the green ball (process ball2) using WASD.
I'm supposed to be able to move black ball (process ball1) using the arrow keys AND the green ball at the same time.
I can move the black ball without the green ball code, and I can move the green ball without the black ball code.

ANY help is greatly appreciated

code:

put "Use the arrow keys to move the ball around, press any other key to stop." delay (2000) cls  % Clear Screen process ball1     setscreen ("graphics")     var key : string (1)     var x, y, r : int     x := maxx div 2 % Start at center     y := maxy div 2 % Start at center     r := 10 % Ball radius     loop         % Draw circle         drawfilloval (x, y, r, r, black)         getch (key)         % Move Left         if key = (KEY_LEFT_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             x := x - r             % Move Right         elsif key = (KEY_RIGHT_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             x := x + r             % Move Up         elsif key = (KEY_UP_ARROW) then             %elsif ord (key) = 200 then             drawfilloval (x, y, r, r, white)             % or use cls             y := y + r             % Move Down         elsif key = (KEY_DOWN_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             y := y - r             % If any other key is pressed, clear screen and exit             %else             %cls             %exit         end if     end loop end ball1 %End process ball1 process ball2 %Begin process ball2     %setscreen ("graphics")     var key : string (1)     var x, y, r : int     x := maxx div 3     y := maxy div 3     r := 10 % Ball radius     loop         % Draw circle         drawfilloval (x, y, r, r, green)         getch (key)         % Move Left         if key = ('a') then             drawfilloval (x, y, r, r, white)             % or use cls             x := x - r             % Move Right         elsif key = ('d') then             drawfilloval (x, y, r, r, white)             % or use cls             x := x + r             % Move Up         elsif key = ('w') then             drawfilloval (x, y, r, r, white)             % or use cls             y := y + r             % Move Down         elsif key = ('s') then             drawfilloval (x, y, r, r, white)             % or use cls             y := y - r             %If any other key is pressed, clear screen and exit             %else             %cls             %exit         end if     end loop end ball2 fork ball1 fork ball2

[/quote]

Thanks in advance.
-Chris

[andrew.]

Well, first you don't ever want to use fork especially for this kind of thing. The only thing fork should be used for is maybe background music in a game. Second, get a pen and paper and organize your code. Group each set of code in a logical order and put it in one main loop. This is a great way to solve any programming problem. I would give you a little more help but I can't really run the code because I'm on my Linux machine. Just try my suggestion and then post it here or PM it and I'll help you with it.

[Tony]

andrew is completely right. To illustrate an example:

Lets say you press KEY_LEFT_ARROW.

getch (key) is called from ball2 (try pick more descriptive names).

The said block of code doesn't know what to do with this particular key.

------

Also, getch reads one character at a time, from the buffer. Which is clearly now what you are trying to do in your program. Look into Input.KeyDown() instead.

[SunsFan13]

Thanks for the advice Andrew, unfortunately "forking it" is how my teacher wants it to be done..
Another kid in the class has his working VERY similar to mine, I think I'm just missing something little, or have something that doesn't need to be there, that kind of thing. The teach wants them organized in procedures, then to use fork in the end to call them.

[SunsFan13]

Alright Tony, tried your way

code:

put "Use the arrow keys to move the ball around, press any other key to stop." delay (2000) cls  % Clear Screen process ball1     setscreen ("graphics")     var key : array char of boolean     var x, y, r : int     x := maxx div 2 % Start at center     y := maxy div 2 % Start at center     r := 10 % Ball radius     loop         % Draw circle         drawfilloval (x, y, r, r, black)         Input.KeyDown (key)         % Move Left         if key (KEY_LEFT_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             x := x - r             % Move Right         elsif key  (KEY_RIGHT_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             x := x + r             % Move Up         elsif key  (KEY_UP_ARROW) then             %elsif ord (key) = 200 then             drawfilloval (x, y, r, r, white)             % or use cls             y := y + r             % Move Down         elsif key (KEY_DOWN_ARROW) then             drawfilloval (x, y, r, r, white)             % or use cls             y := y - r             % If any other key is pressed, clear screen and exit             %else             %cls             %exit         end if     end loop end ball1 %End process ball1 process ball2 %Begin process ball2     %setscreen ("graphics")     var key :array char of boolean     var x, y, r : int     x := maxx div 3     y := maxy div 3     r := 10 % Ball radius     loop         % Draw circle         drawfilloval (x, y, r, r, green)         Input.KeyDown (key)         % Move Left         if key  ('a') then             drawfilloval (x, y, r, r, white)             % or use cls             x := x - r             % Move Right         elsif key  ('d') then             drawfilloval (x, y, r, r, white)             % or use cls             x := x + r             % Move Up         elsif key  ('w') then             drawfilloval (x, y, r, r, white)             % or use cls             y := y + r             % Move Down         elsif key  ('s') then             drawfilloval (x, y, r, r, white)             % or use cls             y := y - r             %If any other key is pressed, clear screen and exit             %else             %cls             %exit         end if     end loop end ball2 fork ball1 fork ball2

The ball however just disappears, this is probably because I've got it drawing a white circle when I press said key.
How do I get it to redraw its self in the new position?

[SunsFan13]

You guys can delete this thread if need be.
I've figured it out.
I needed to add a delay after each key stroke.

[Civik]

Why erase it? Someone else might find this useful later.

[Prince Pwn]

andrew: Turing and Ready run under emulation in Linux, but the fonts are a bit cut off so you have to mess with them.