What's wrong with this code?

[sandra]

Hi all of you!

I'm doing a small game using DDraw, it's called CrossBall.
A ball is moving along the horizontal part of a cross. The user has to try and stop it in the middle of the cross. If he succeeds in doing so, another ball will start moving on the vertical part, so he has to stop aver the first one.
The problem is, that when the first ball stops in the middle, the second one appears on the vertical part but doesn't move.

This is the code in general:

'First, the BallType
BallType
    XPosition 'Sets the X-coordinate
    Yposition 'Sets the Y-coordinate
    Xspeed 'A constant added to the X-coordinate simulating the ball's speed in the x direction
    yspeed 'A constant added to the Y-coordinate simulating the ball's speed in the y direction
End Type

CrossBall function()
    setHorizontalBall
    Do
    DoEvents
        MoveHorizontalBall
        If vbKeySpace Then
            'if Ball is in the middle
                ball.Xspeed = 0
                SetVerticalBall
                Do
                DoEvents
                    MoveVerticalBall
                    if vbKeySpace
                        'if bal is over the other one
                            ball.yspeed = 0
                            Exit Do
                    End If
                Loop
        End If
    Loop
End Function

SetVertical and SetHorizontal are sub's that set the balls in theie places and sets their speeds.
MoveHorizontal: ball.Xposition=Ball.Xposition+Ball.Speed
MoveVertical: ball.yposition=ball.yposition+ball.speed

I think that's it.

Thank you all for your help.

[TMTOMH]

I'm pretty new at this stuff, but it looks to me like it may be a problem with the first "if vbKeySpace". Perhaps that is not always true when you are expecting the vertical ball movement to occur. I think You need to do the vertical movement outside of that if statement.



Just my $.02 and overpriced at that.

[Fox]

TMTOMH, that was pseudo-code ^_^

---

If vbKeySpace Then

How do you realize that? Do you have a keys buffer? If so you'd need to clear that buffer after this line, because else Space would still be 'pressed' and the next check for Space would return true.. see?

[sandra]

No Fox actually I have a "buffer" for keys pressed. It's an array holding all the keys.
What hapens is:

sub form_keydown(anykey) (or something like that)
  key(anykey)=true
end sub

sub form_keyup(anykey)
  key(anykey)=false
end sub

[Fox]

Read my posts carefully I said "Do you have a keys buffer? If so you'd need to clear that buffer after this line.."

So after checking if space is true do:

Key( vbKeySpace ) = False

[sandra]

Ok! I'm sorry. Now I got what you mean.

Ok, I'll try it