help mapping latitude, longitude in svg
 

this is a general programming question but i'm using java so i'm posting it here...

i am trying to map geographical coordinates in a plane. given are 2 geographical points (latitude longitude), the width and height of the svg in pixels and a third geographical point. given the values, i would like to know what will be the coordinates of the third geographical point in the svg... i am having trouble finding a right formula for this one.. what i did is i subtract lat1 from lat2 and given the difference, i divided it with the width of the svg file. i am thinking that this will give me n decimal per pixel... to be able to map the third geographical point in the svg, i subtracted lat1 from the latitude of the third point and divided it with the n decimal per pixel... i think that my math is right but apparently it's not.. please correct me because the coordinates is way off.. :confused: thanks..

http://i163.photobucket.com/albums/t...lustration.png

please help me!!!

Re: help mapping latitude, longitude in svg
 

OK, based on that drawing, I've come up with this.



This is specialized to those particular coordinates, but you can look at it like this....

If you used the first 2 coordinates to form a rectangle, then it would be:


Basically, just finding a ratio of how far in the 3rd point is in the x direction, how far in the y direction.

Then apply it to the SVG dimensions to find the coordinates.