[Chicago] My mind is not seeing it

[Randy Baxley]

It sounds like you have put me on the right track but I will likely not
have a chance to actually look at it until Friday.  Thank you.


On Wed, Jan 16, 2013 at 12:47 PM, Adam Bain <bainada.iit at gmail.com> wrote:

> Randy,
>
> I don't see the bug exactly as you describe it. What I see is the ball
> speeds up only when hitting the paddles (not when hitting the gutter, I
> tried letting the ball hit the gutter a lot and saw no velocity increase
> until I hit it with a paddle).  This seems to be the intended behavior as
> you increase the horizontal component of the velocity by 10% each time
> theres a paddle hit.
>
> ball_vel[0] = ( -ball_vel[0] ) * 1.0
>
> This horizontal speed does not get reset in magnitude after a point is
> scored but it does get reversed (this doesn;t really affect the bug, but I
> can't really tell if this is intended) :
>
> else:
>             ball_vel[0] = ( -ball_vel[0] )
>
> To get to the meat of the bug though, what is happening is that you are
> multiplying up the magnitude of the horizontal by 1.1 each hit (e.g 4,.4.4,
> 4.84, ~5.32, ~5.86, ~6.44, ~7.09). As you noted this does eventually go
> above 7, but consider what the code does in that situation.
>
> if ( ball_pos[1] <= bottom1 ) and ( ball_pos[1] >= top1 ): # You hit left
> paddle
>     # increase abolute velocity 10 percent but to no more than 7
>             print ' hit paddle '
>             if abs( ball_vel[0] ) < 7:
>                 ball_vel[0] = ( -ball_vel[0] ) * 1.1
>
> This means that when the paddle is lined up for a hit, it will pass the
> first if, print the 'hit paddle' and then fail the second if condition,
> which means the ball never gets reversed.
>
> To the second part of your question, I assume you are asking why this
> eventually gets counted as a point.  This is simply because as the ball
> goes through the paddle, it will eventually no longer satisfy the first if
> condition of being between the two paddle boundaries (especially since ht
> user wont be able to see the ball anymore) and will fall through to the
> else, which will run the 'point scored' code,
>
> There are a couple of simple ways to close this bug (depending on how
> strictly you want to enforce the 7 speed limit), but rather than spelling
> them out for you hopefully, this helps you getting on the right track to
> coming up with a solution. Post back if you're still having trouble.
>
>
> Adam Bain
>
>
> On Wed, Jan 16, 2013 at 11:41 AM, Randy Baxley <randy7771026 at gmail.com>wrote:
>
>>
>> Would someone play this game and tell me why towards the end the ball
>> speed increases when hitting the gutters and fails the test when hitting
>> the paddles and then passes the test?
>>
>> http://www.codeskulptor.org/#user8-paYp6vO6lS-19.py
>>
>> TIA,
>>
>> Randy
>>
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>>
>>
>
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>
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