It is currently 27 Jul 2017, 18:51

All times are UTC + 1 hour [ DST ]




Post new topic Reply to topic  [ 23 posts ]  Go to page Previous  1, 2, 3
Author Message
 Post subject: Re: Challenge: Make the fastest island selection compound
PostPosted: 10 Nov 2012, 02:52 
Offline
Moderator
User avatar

Joined: 26 Sep 2009, 15:51
Posts: 1296
Location: Bonn, Germany
some compounds here I made recently, work reasonably fast, based of Guillaume's method, but simplified
#1: "Initialize Island Lookups"
#2: "Get Island Locations": per point, fetches array of locations of all island points for subsequent attribute lookups, requires Compound 1 executed

Don't know how much this is already covered in this thread, just needed some quick search&paste place to post this in :)


Attachments:
island.zip [3.54 KiB]
Downloaded 144 times

_________________
Image rray.de, a resource site for softimage, updated Oct 15th 2016
Top
 Profile  
 
 Post subject: Re: Challenge: Make the fastest island selection compound
PostPosted: 11 Nov 2012, 14:19 
Offline

Joined: 27 Apr 2010, 16:10
Posts: 9
I never seemed to have any problems with Oleg's compound so I'm not sure this variant will work on other machines but in the attached scene I've used the same basic technique as Oleg (i.e. growing outwards from the initial vertices attached to the target poly) but tried to filter the search vertices so that you're not iterating over the same points. I set up a variant of the test scene with highly subdivided topology and my tree executes in about 1.75s and Oleg's in about 7.5s (on my machine).

http://www.exch.demon.co.uk/xsi/files/islDetectionChallenge_JJ.rar

Let me know if this a) works and b) if my timings are grossly wrong! On the surface it seems to do the job. The scene is 2013 SP1.


Top
 Profile  
 
 Post subject: Re: Challenge: Make the fastest island selection compound
PostPosted: 12 Nov 2012, 15:32 
Offline

Joined: 27 Apr 2010, 16:10
Posts: 9
For completeness, just updated the scene to include a comparison of the two basic techniques a) iterating outwards as Oleg does and b) identifying all the polygon islands first and then deriving the island-to-be-actioned from the polygon index (similar to Reinhard's compounds above). The former is always about 30% quicker but the latter does give you the polygon island indices as a bonus.

http://www.exch.demon.co.uk/xsi/files/index_to_island.rar


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 23 posts ]  Go to page Previous  1, 2, 3

All times are UTC + 1 hour [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group