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I want to convert (google sourced) longitude and latitude coordinates to x and y to place points on a SVG map

I can get the longitude converted to X but I can't nail latitude.

http://jsfiddle.net/chrisloughnane/an3BZ/17/

  • red dots = place holders
  • green dot = calculated position from longitude/latitude

I have read so much about Mercator projections and other projection system API's I am now completely confused. I also followed Proj4JS library threads but couldn't find an example that was close to my task.

I attempted to emulate @Raphael Wichmann and @betamax solution, unfortunately I got something wrong.

Could someone please have a look at my jsfiddle and see if it's an obvious mistake?

The second test function secondconvert(latitude, longitude) (bottom of javascript pane) provides me with a reasonably accurate x coordinate i.e. if I manually enter the y coordinate b.ylat change to 265 it covers my left red dot place holder nearly perfectly.

I think I'm close, any help would be really appreciated.

Note: the longitude/latitude bounds I used for my SVG map are best guesstimates, worked surprisingly well for the longitude calculation.

tia.


Original SVG from here.

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1 Answer 1

up vote 0 down vote accepted

This question was answered by @acraig5075 here.

After correcting my mistake and adjusting southern latitude I get: http://jsfiddle.net/chrisloughnane/an3BZ/40/

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@Chris- rather than editing your title to say "solved", please click the "checkmark" next to your answer to mark it as "accepted". Thanks. –  RyanDalton Sep 4 '12 at 14:28
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