Random Image
Site Visitor Trivia

Visits today:1
Visits yesterday:5
Visits in this month:53
Visits in previous month:27
Visits in this year:330
Visits in previous year:66
Visits total:169693
Max.daily visits:748
Day of max visits:2013-06-12
Max.monthly visits:4565
Month of max visits:2018-03
Impressions today:9
Impressions yesterday:8
Impressions this month:364
Impressions total:667974
Bots today:8
Date since:2010-08-27
Visitors By Country
Top 5:
Unknown flag 44%Unknown (74219)
United States flag 10%United States (16384)
China flag 5%China (8748)
Germany flag 5%Germany (7750)
Russian Federation flag 4%Russian Federation (7524)
169693 visits from 183 countries

Projects

I began writing MathGeoLib some time around the summer of 2011. The library has come a long way since and it now contains a range of common geometry types and different operations related to them. One of the recurring issues has been the problem of computing minimal enclosing shapes for 3D meshes for culling and collision detection. Code for generating minimum enclosing axis-aligned bounding boxes (AABB) was included in MathGeoLib right from the start, and finding minimum enclosing spheres was added almost immediately in November 2011. Convex hull computation was added in 2012. These covered three very common geometric collision shapes, but for oriented bounding boxes (OBB), another very common collision primitive, MathGeoLib did not have anything to offer for a long time. This was due to the fact that there did not really exist any good algorithms for finding minimum enclosing OBBs, and brute force or principal component analysis (PCA) were the most common approaches. This means a choice of getting either practically the optimal result extremely slowly, or possibly an arbitrarily bad result very quickly. A number of intelligent numerical optimization algorithms have been crafted to help this issue, but since those are not able to give any guarantees either, and I could not find any reproducible implementations, they did not feel right.

Last Updated (Friday, 05 June 2015 13:08)

Read more...

 
More Articles...