On Feb 18, 2009, at 15:33, Mark Burton wrote:
Not much too report after spending quite a few hours on this last night.
I am trying to understand why some inter-tile connections are good and a lot are bad. I have tried moving points around and rounding coordinates and stuff like that but with no knowledge gained about from the fact that it appears you can zero the bottom 2 bits of the lat/lon values in the nod3 record and it doesn't stop a good inter-tile connection from working. If you zero 3 bits, that stops it being usable.
I have tried limiting the size of the NOD3 section to 16 entries, it made no difference.
Not sure why I never noticed before, but it seems the NOD3 entries have to be ordered by coordinates! Seems obvious, right? The sample I've just checked seems to have them ordered by increasing longitude, but it doesn't have boundary nodes on all edges, so I'm not quite sure this is right... Combined patch against current trunk attached, feedback welcome. Cheers Robert