[mkgmap-dev] [Patch v3] LocationHook with new Quadtree

Thu Jan 12 21:26:50 GMT 2012

Hi Gerd,

some ideas and questions:

* BoundaryQuadTree.Node.add always performs a costly intersect of the 
area, also if the area is completely within the bbox. Maybe it's better 
first to check if the bbox contains the area (or area.getBounds()).

* I don't understand the following part in Node.add:
---
// optimization: don't add equal areas, only add the tags
// we test only against the last element because that is likely
// to match
if (numNodes > 0 && a.equals(nodes.get(numNodes-1))){
   addMissingTags(nodes.get(numNodes-1).tags, bTags);
   return;
}
---
a is an area and nodes.get returns a NodeElem so equals will always be 
false.
I think you want to compare to nodes.get(..).area but I do not 
understand that either. Why should two areas be equal?

* LocationHook.mkgmapTagsArray starts with an empty string element. I 
don't like that.

* for (int i = 12; i >= 1; --i){
	if (elem.getTag(mkgmapTagsArray[i] ) != null)
		res |= (1 << i);
}

=>

for (int i = 0; i mkgmapTagsArray.length; i++) {
	if (elem.getTag(mkgmapTagsArray[i] ) != null)
		res |= (1 << i);
}

Counting down is quite unusual and should only be done if there is a 
real reason for it.

* I don't understand why you need a merge() method. Could you explain 
what you are doing in this method and why it's required?

WanMil

> Hi,
>
> now complete and based on r2167.
>
> Gerd
>
> http://gis.638310.n2.nabble.com/file/n7181669/locationHook_speedup_v3.patch
> locationHook_speedup_v3.patch
>
> --
> View this message in context: http://gis.638310.n2.nabble.com/Patch-v3-LocationHook-with-new-Quadtree-tp7181669p7181669.html
> Sent from the Mkgmap Development mailing list archive at Nabble.com.
> _______________________________________________
> mkgmap-dev mailing list
> mkgmap-dev at lists.mkgmap.org.uk
> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev