Hi,
It would probably be better to create a grid of subdivisions and cut the roads at nodes near the boundary so that there is a lot less overlapping. I've no idea how much, if any, difference it would make though, and it would entail a fairly substantial re-write.
Do you still consider this idea? Cgpsmapper supports parameter "TRESIZE". I assume that this parameter define size of subdivision in TRE. It could be equivalent to definition in file MapSplitter.java: public static final int MAX_DIVISION_SIZE = 0x7fff; Using "TRESIZE" in cgpsmapper directly influence 2 feature of resulting img: file size and processing speed in device. And there are real gains in map redraw speed when using small values for TRESIZE. I usually set it for 511. I have experimenting a bit with MAX_DIVISION_SIZE in mkgmap. I have observed increase in file size, when using small value, but no increase in processing speed. I think this discussion gives some explanations. As I understand, mkgmap doesn't split map objects to fit subdivisions. So there is no gain from using smaller subdivisions, because there is no reduction in processed objects size. I would expect that proper truncating objects to subdivisions could be another big improvement for mkgmap. Please, don't abandon this idea. -- Best regards, Andrzej