[postgis-devel] Re: [HACKERS] GiST -- making my index faster makes is slower

[David Blasby]

I tracked the problem down to the "penalty" function used to build the 
tree.   Basically, it compares the area of the bounding boxes.

There wasnt enough precision in the area calculations - instead of 
giving 0.0 it would give numbers in the[+-]10^-6 range.  This really 
screwed up how the tree was being built.

I cast the float to doubles when calculating area, and it all works well 
now.

dave