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#1 2012-02-24 00:26:44
- RedAlertFan
- New Scratcher
- Registered: 2011-01-21
- Posts: 6
Finding smallest distance between several objects
I need to find the object with the smallest distance out of 14 others to one object, but they constantly move, and the script must recalculate the minimum distance constantly. I cannot figure out how.
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#2 2012-02-24 01:05:17
Re: Finding smallest distance between several objects
http://scratch.mit.edu/projects/Magnie/718306, it detects which one is closest to the center.
You can probably put a forever loop around it so it'll continue to detect the closest one.
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#3 2012-02-24 06:27:11
- RedAlertFan
- New Scratcher
- Registered: 2011-01-21
- Posts: 6
Re: Finding smallest distance between several objects
Thanks. Is there a way to use that information to make it point to the closest one?
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#4 2012-02-24 06:48:05
Re: Finding smallest distance between several objects
RedAlertFan wrote:
Thanks. Is there a way to use that information to make it point to the closest one?
Once you know which sprite is closest, you can use the following simple block:
point towards (closest sprite name)or
if <(name) = [a]> point towards[a v] else point towards [b v] enddepending on your needs...
Include it in the forever loop after the closest sprite has been calculated
Last edited by LS97 (2012-02-24 06:49:43)
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#5 2012-02-24 12:55:01
Re: Finding smallest distance between several objects
Pythagoras theorem
c^2 = a^2 + b^2
Put the names of the sprites in a list called sprites (or anything, really) with the exception of the sprite you are comparing to.
Forever set (ShortestDistance) to [1000] set (Counter) to [0] Repeat [13] change (counter) by [1] set (DistanceX) to <[abs v] of <([x position v] of (item (counter) of [Sprites v])) - ([x position v] of [sprite v])>> set (DistanceY) to <[abs v] of <([y position v] of (item (counter) of [Sprites v])) - ([y position v] of [sprite v])>> set (DistanceXSq) to <(DistanceX) * (DistanceX)> set (DistanceYSq) to <(DistanceY) * (DistanceY)> if <[<[sqrt v] of <(DistanceXSq) + (DistanceYSq)>>] < [(ShortestDistance)]> set (ShortestDistance) to <[sqrt v] of <(DistanceXSq) + (DistanceYSq)>> set (ClosestSprite) to (Counter) end endThe text bits are temporary until I can fix em.
EDIT: It works.
Example project here.
Feel free to download it and view the scripts there, they probably will be more understandable and clear. I will add comments shortly.
Also feel free to use the script if you want to.
Last edited by Smozzick (2012-02-24 13:14:24)
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