Moving the ball in Brick Breaker.

[miller6]

What is it you are trying to achieve?
I am trying to move the ball (in this case a snowflake) just like the ball in breakbreaker. Where it bounces off the side of the wall when it hits it.

What is the problem you are having?
Moving the ball all around the screen and showing the movement of it.


Describe what you have tried to solve this problem
Alot. I have tried different ways of moving it, but still have problems.


Post any relevant code (You may choose to attach the file instead of posting the code if it is too long)
This is the main part of moving the ball. Not entire program posted.

Turing:

var x_s, y_s : int := 1  % sflake coordinates var width_s : int := 59 % sflake width var sflake : int := Pic.FileNew ("sflake.gif") loop x_s := Rand.Int (1, maxx) y_s := Rand.Int (1, maxy) Pic.Draw (sflake, x_s, y_s, picMerge) if (x_s + width_s) >= (maxx - 1) then         x_s := x_s * -1     elsif (y_s + width_s) >= (maxy - 1) then         y_s := y_s * -1     elsif (x_s - width_s) <= 1 then         x_s := 2     elsif (y_s - width_s) <= 1 then         y_s := 2      end if delay (500) end loop

Please specify what version of Turing you are using
4.1.1

[miller6]

sorry for the double attachment.

[Turing_Gamer]

Have 2 separate variables: speed and direction. Then do the following...

Turing:

loop     x := x + xdir     y := y + ydir     if x >= maxx then         xdir := xdir * 1     elsif x <= 0 then         xdir := xdir * 1     end if     % Repeat for y coordinate end loop

Puting how fast and what direction is easy. Use either boolean or if statements.

[TheGuardian001]

Turing_Gamer @ Tue Jan 19, 2010 5:34 pm wrote:

Have 2 separate variables: speed and direction. Then do the following...

Turing:

loop     x := x + xdir     y := y + ydir     if x >= maxx then         xdir := xdir * 1     elsif x <= 0 then         xdir := xdir * 1     end if     % Repeat for y coordinate end loop

Puting how fast and what direction is easy. Use either boolean or if statements.

I think you probably meant

code:

xdir = -xdir %invert the x velocity

since multiplying by 1 won't do anything...

[andrew.]

Or you can multiply by -1 (which was probably his intention).

Turing:

xdir *= -1 % invert the x component

[miller6]

okay, so it is still doing the same thing, its just popping up in random places. It is not travelling from each position to each position. This is the changed code:

Turing:

var x_s, y_s : int := 1  % sflake coordinates var xdir_s, ydir_s : int := 1 var width_s : int := 59 % sflake width var sflake : int := Pic.FileNew ("sflake.gif") loop     x_s := Rand.Int (1, maxx)     y_s := Rand.Int (1, maxy)     x_s := x_s + xdir_s     y_s := y_s + ydir_s     Pic.Draw (sflake, x_s, y_s, picMerge)         if (x_s + width_s) >= (maxx - 1) then         xdir_s := xdir_s * -1     elsif (y_s + width_s) >= (maxy - 1) then         ydir_s := ydir_s * -1     elsif (x_s - width_s) <= 1 then         xdir_s := xdir_s * -1     elsif (y_s - width_s) <= 1 then         ydir_s := ydir_s * -1     end if     delay (500) end loop

[miller6]

Okay, so now i changed it for it to bounce off the side at a different angle each time but still am having trouble getting it to move in one continious motion.

Here is the new coding:

Turing:

var WinId : int var x_s, y_s : int := 1  % sflake coordinates var width_s : int := 59 % sflake width var x_angle, y_angle, x_angle2, y_angle2, x_angle3, y_angle3 : int := 1 var sflake : int := Pic.FileNew ("sflake.gif") WinId := Window.Open ("position:centre;centre,graphics:1010;695") loop     x_s := Rand.Int (1, maxx)     y_s := Rand.Int (1, maxy)     x_angle := Rand.Int (-3, -1)     y_angle := Rand.Int (-3, 3)     x_angle2 := Rand.Int (-3, 3)     y_angle2 := Rand.Int (-3, -1)     x_angle3 := Rand.Int (1, 3)     y_angle3 := Rand.Int (1, 3)     if (x_s + width_s) >= (maxx - 1) then          y_s := y_s + y_angle     elsif (y_s + width_s) >= (maxy - 1) then         y_s := y_s + y_angle2         x_s := x_s + x_angle2         elsif (x_s + width_s) <= 1 then         x_s := x_s + x_angle3         y_s := y_s + y_angle     elsif (y_s + width_s) <= 1 then         y_s := y_s + y_angle3         x_s := x_s + x_angle     end if         Pic.Draw (sflake, x_s, y_s, picMerge)     delay (500) end loop

[miller6]

sorry, i missed part of it.

Turing:

var WinId : int var x_s, y_s : int := 1  % sflake coordinates var width_s : int := 59 % sflake width var x_angle, y_angle, x_angle2, y_angle2, x_angle3, y_angle3 : int := 1 var sflake : int := Pic.FileNew ("sflake.gif") WinId := Window.Open ("position:centre;centre,graphics:1010;695") loop     x_s := Rand.Int (1, maxx)     y_s := Rand.Int (1, maxy)     x_angle := Rand.Int (-3, -1)     y_angle := Rand.Int (-3, 3)     x_angle2 := Rand.Int (-3, 3)     y_angle2 := Rand.Int (-3, -1)     x_angle3 := Rand.Int (1, 3)     y_angle3 := Rand.Int (1, 3)     if (x_s + width_s) >= (maxx - 1) then          x_s := x_s + x_angle         y_s := y_s + y_angle     elsif (y_s + width_s) >= (maxy - 1) then         y_s := y_s + y_angle2         x_s := x_s + x_angle2     elsif (x_s + width_s) <= 1 then         x_s := x_s + x_angle3         y_s := y_s + y_angle     elsif (y_s + width_s) <= 1 then         y_s := y_s + y_angle3         x_s := x_s + x_angle     end if     Pic.Draw (sflake, x_s, y_s, picMerge)     delay (500) end loop

[Insectoid]

code:

x_angle := Rand.Int (-3, -1)     y_angle := Rand.Int (-3, 3)     x_angle2 := Rand.Int (-3, 3)     y_angle2 := Rand.Int (-3, -1)     x_angle3 := Rand.Int (1, 3)     y_angle3 := Rand.Int (1, 3)

This part should not be in the loop. You are selecting a random direction every time the loop iterates, which makes your ball fuffle around aimlessly.