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#1 2013-05-02 08:35:29
- PERCE-NEIGE
- Scratcher
- Registered: 2009-05-24
- Posts: 9
A parabolic equation
Hi,
I have a character who throw a ball to another one in one of my script, I want the ball to follow a parabolic way. I don't remember what is the equation for a parbolic throw?
Please, give me hints one by one, I'd like to see if I can do it by myself with your hints.
If I'm stuck, I'll ask you for other hints on this same thread.
Thanks!
Frenchie :-)
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#2 2013-05-02 12:29:35
- firedrake969_test
- Scratcher
- Registered: 2012-08-08
- Posts: 500+
Re: A parabolic equation
Here's some pseudocode for you to get an idea:
go to start
set yv to (y velocity whatever you want, about 5-15)
set xv to (x velocity whatever you want, about 15+)
forever
change x by xv
change y by yv
set yv to yv * .98
set xv to xv * .98
change yv by -1
Hope that helped!
Oh, and welcome, Snowdrop!
Last edited by firedrake969_test (2013-05-02 12:56:14)
Alt of Firedrake969.
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#3 2013-05-02 16:01:01
- ErnieParke
- Scratcher
- Registered: 2010-12-03
- Posts: 1000+
Re: A parabolic equation
firedrake969_test wrote:
Here's some pseudocode for you to get an idea:
go to start
set yv to (y velocity whatever you want, about 5-15)
set xv to (x velocity whatever you want, about 15+)
forever
change x by xv
change y by yv
set yv to yv * .98
set xv to xv * .98
change yv by -1
Hope that helped!
Oh, and welcome, Snowdrop!
Ummm... That wouldn't follow a parabolic arch. The y velocity would eventually flatten out to 50, and would never exceed that, making this some weird equation that's not parabolic, which isn't needed here.
To PERCE-NEIGE:
Well, since your asking for the equation and not some code, here are two hints:
-b
___
2a
x^2
I hope that this helps!
With regards,
ErnieParke
Last edited by ErnieParke (2013-05-02 16:02:01)
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#4 2013-05-03 02:30:13
- PERCE-NEIGE
- Scratcher
- Registered: 2009-05-24
- Posts: 9
Re: A parabolic equation
Thank you! Just perfect.
Yes, -b/2a reminds me something! I brainstorm and I come back when I'm free.
Frenchie :-)
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#5 2013-05-03 16:29:10
Re: A parabolic equation
ErnieParke wrote:
firedrake969_test wrote:
Here's some pseudocode for you to get an idea:
go to start
set yv to (y velocity whatever you want, about 5-15)
set xv to (x velocity whatever you want, about 15+)
forever
change x by xv
change y by yv
set yv to yv * .98
set xv to xv * .98
change yv by -1
Hope that helped!
Oh, and welcome, Snowdrop!Ummm... That wouldn't follow a parabolic arch. The y velocity would eventually flatten out to 50, and would never exceed that, making this some weird equation that's not parabolic, which isn't needed here.
I think it's like a version with air resistance, except the formula isn't exactly right (I think the air resistance force was proportional to something like v^2, not v.
Tip of the whatever: Don't post in threads older than 2 weeks unless your post will actually be useful.
It's the last day of 1.4! *cries* (quote from NeilWest, rest by me) by the time you read this it probably will be 2.0
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#6 2013-05-04 08:56:47
- Firedrake969
- Scratcher
- Registered: 2011-11-24
- Posts: 1000+
Re: A parabolic equation
ErnieParke wrote:
firedrake969_test wrote:
Here's some pseudocode for you to get an idea:
go to start
set yv to (y velocity whatever you want, about 5-15)
set xv to (x velocity whatever you want, about 15+)
forever
change x by xv
change y by yv
set yv to yv * .98
set xv to xv * .98
change yv by -1
Hope that helped!
Oh, and welcome, Snowdrop!Ummm... That wouldn't follow a parabolic arch. The y velocity would eventually flatten out to 50, and would never exceed that, making this some weird equation that's not parabolic, which isn't needed here.
To PERCE-NEIGE:
Well, since your asking for the equation and not some code, here are two hints:-b
___
2ax^2
I hope that this helps!
With regards,
ErnieParke
Actually it would...
Even if it theoretically wouldn't work, it works in practice.
EDIT: E-P, if you're reading this, it does work. I'm uploading a proof-of-concept project soon. So yes, it does work, P-N.
Last edited by Firedrake969 (2013-05-05 16:17:39)
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