Converting Longitude & Latitude to X Y on a map with Calibration points

coordinates, geocoding, gps, latitude-longitude

Solution

Here's what worked for me, without so much bs.

int x =  (int) ((MAP_WIDTH/360.0) * (180 + lon));
int y =  (int) ((MAP_HEIGHT/180.0) * (90 - lat));

The lat,lon coordinates were given to me by Android devices. So they should be in the same standard used by all Google Earth/Map products.

Problem

If i have a jpeg map with size sizeX, sizeY and some calibration points on the map (X, Y, Lon, Lat) What would be the algorithm for calculating the corresponding XY point in the map with a given Longitude / Latitude pair?

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