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Determining whether or not a polygon (2D) has its vertices ordered clockwise or counterclockwise(T)

Fri, 2009-11-13 22:49 — leelight

Org link: http://debian.fmi.uni-sofia.bg/~sergei/cgsr/docs/clockwise.htm

 

EPSG:4326(WGS84) WMS in Openlayers and EPSG:900913 Google Map

Tue, 2009-05-12 01:32 — leelight

In SUAS Map Server I used Openlayers to display WMS layers in EPSG:4326 SRS with Google Map, I found the WMS overlays are always be transformed, now i kown the reason. EPSG:4326 != EPSG:900913

Get CellId and other Imformation from mobile phones via J2ME

Mon, 2009-03-30 00:53 — leelight

Without GPS or Network Operator we can still use the Location Based Service, via the help of CellId(Cell ID the location of Cell Identities of GSM-networks). Google has one enormous database of cell ids which are linked to a longitude and latitude position, that why Google Map client know where you are even you have no embedded GPS--it is not open.

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