Search found 14 matches

by olliej
Sun Feb 10, 2019 12:11 am
Forum: General Development
Topic: Performance issues with Wald&havran's nlogn kdtree construction
Replies: 5
Views: 822

Re: Performance issues with Wald&havran's nlogn kdtree construction

I am just doing the naive median split, the problem is doing a median split still requires finding the median element which is an nlogn so you end up with nlog^2n construction. The w&h approach should lead to nlogn construction complexity, but it my implementation is vastly slower (proportionally) t...
by olliej
Fri Feb 08, 2019 8:21 pm
Forum: Visuals, Tools, Demos & Sources
Topic: Glitch Pictures anyone?
Replies: 81
Views: 111834

Re: Glitch Pictures anyone?

Something going very wrong in photon mapping:
Image
by olliej
Thu Feb 07, 2019 8:55 pm
Forum: General Development
Topic: Performance issues with Wald&havran's nlogn kdtree construction
Replies: 5
Views: 822

Performance issues with Wald&havran's nlogn kdtree construction

I've been attempting to implement Wald and Havran's nlogn kdtree construction for a photon map implementation, and it consistently has vastly worse construction perf, and I'm not sure how much is due to splitting semantics. If I implement the naive nlog^2n algorithm using a median split as suggested...
by olliej
Mon Nov 12, 2018 3:13 am
Forum: Visuals, Tools, Demos & Sources
Topic: Glitch Pictures anyone?
Replies: 81
Views: 111834

Re: Glitch Pictures anyone?

Behold the majesty of an exceptionally bug in my BVH construction - a copy/paste error that resulted in completely bogus behavior when merging bounding boxes:
weird iterative bvh results.png
weird iterative bvh results.png (48.63 KiB) Viewed 1001 times