http://blogs.msdn.com/isaac/archive/2008/03/01/basic-multi-level-grids.aspxHi Folks, Last time , we highlighted several problems with a simple grid index. If you don't recall---and since it's been a while, that wouldn't be a surprise---you may want to review them. In this post I'll start to describe how we get around them. Inen-USCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/isaac/archive/2008/03/01/basic-multi-level-grids.aspx#8369563Tue, 08 Apr 2008 21:17:39 GMT91d46819-8472-40ad-a661-2c78acb4018c:8369563Isaac @ MSDN<p>Hi Folks, In my last indexing post , I filled in most of the details about our multi-level grid index.</p> http://blogs.msdn.com/isaac/archive/2008/03/01/basic-multi-level-grids.aspx#9125792Wed, 19 Nov 2008 23:17:55 GMT91d46819-8472-40ad-a661-2c78acb4018c:9125792tanoshimi<p>My understanding is that the grid cells added to an index specify a coverage mask as to whether they are touched, partially covered, or interior to the geometry in question...</p> <p>Based on that first coverage mask, &quot;touched&quot;, shouldn't the large top-level cell in the top-left corner of the grid be included in the index as well? On my fuzzy monitor, it certainly looks like it 'touches' the geometry at the very corner (or is there a bit of whitespace between them that I can't see?!)</p> http://blogs.msdn.com/isaac/archive/2008/03/01/basic-multi-level-grids.aspx#9441561Mon, 23 Feb 2009 20:41:35 GMT91d46819-8472-40ad-a661-2c78acb4018c:9441561winzo<p>why did not you choose to make a r-tree instead of, which should be faster ?</p>