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Question about video 4.3
http://forum.planetchili.net/viewtopic.php?f=3&t=4189
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Author:  mrselfdestructr [ October 6th, 2017, 12:50 am ]
Post subject:  Question about video 4.3

I just started watching these videos very inexperience with coding but trying my best so go easy on me.

I would like to know when we set the code to stop the instant increase in velocity while holding the key down that this code doesn't work.

So I have (bool StopIncrease = false;)

if (wnd.kbd.KeyIsPressed(VK_UP)) {
if (StopIncrease) { <------from my understanding this doesn't run unless true right?
StopIncrease = false;
}
else <-------- So this runs making StopIncrease = true;
{
vy = vy - 1;
StopIncrease = true;
}
}

So my questions is when it runs

if(StopIncrease) <---this is true now?
{
StopIncrease = false;
}

So why does it not set it to false the next time around?

Author:  cameron [ October 6th, 2017, 1:10 am ]
Post subject:  Re: Question about video 4.3

if statements check to see if what is in the () evaluates to true. Operators such as == < > <= >= ! all return boolean values. If you simply put a variable inside the such as if(var) then it checks to see if var == true.

In summary
if(var) same as if(var == true)
if(!var) same as if(var == false)

Author:  mrselfdestructr [ October 6th, 2017, 1:23 am ]
Post subject:  Re: Question about video 4.3

So when my program runs and StopIncrease = true;
shouldn't this make it false? for the next frame?

if(StopIncrease){
StopIncrease = false;
}

Author:  chili [ October 6th, 2017, 1:31 am ]
Post subject:  Re: Question about video 4.3

Yes, that will make it false. And then the next frame after that it will be made true. It will toggle with a period of 2 frames (frequency of 0.5 frames) ;)

Author:  mrselfdestructr [ October 6th, 2017, 1:40 am ]
Post subject:  Re: Question about video 4.3

if (wnd.kbd.KeyIsPressed(VK_UP)) {
if (StopIncrease) {
}
else {
vy = vy - 1;
StopIncrease = true;
}
}
else
{
StopIncrease = false;
}

So the way you did it Chili does it toggle within (one) frame instead of (two)?

Author:  chili [ October 6th, 2017, 2:00 am ]
Post subject:  Re: Question about video 4.3

It will not toggle at all. It will wait until key has been released before resetting StopIncrease to false.

Author:  mrselfdestructr [ October 6th, 2017, 2:09 am ]
Post subject:  Re: Question about video 4.3

I think I get it, so the way I did won't stop the cursor from getting faster and faster because it doesn't care if my button has been released or not so it keeps adding more and more.

While your way says if the button has not been released don't add anymore.

right?

Author:  chili [ October 6th, 2017, 3:15 am ]
Post subject:  Re: Question about video 4.3

Yup, it remembers if the button has been pressed in a previous frame, and does not add anymore.

Not until it is released, which resets the inhibiting variable and allows a subsequent press to trigger another add.

Author:  mrselfdestructr [ October 6th, 2017, 11:20 pm ]
Post subject:  Re: Question about video 4.3

Thank you for the explanation!

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