Here's another link for you:

http://econym.org.uk/gmap/customflat.htm

It uses version 2 of the API so not entirely useful to you, but it
does show the theory of creating a cartesian projection.

Note that a cartesian projection will draw your cartesian coordinates
exactly where they should be, using the API's built in Mercator
projection could cause problems as it will assume your game's surface
is a sphere and make appropriate corrections.

Martin.


On May 29, 5:48 am, Martin™ <[email protected]> wrote:
> Have you seen this page:
>
> http://code.google.com/apis/maps/documentation/javascript/maptypes.ht...
>
> You say that you have many (cartesian?) coordinates already - what is
> the range of these coordinates?
> Could you normalise all your coordinates so X and Y values range from
> 0 to 256?
> If you could do that then your coordinates would essentially be what
> Google call 'World Coordinates'.
> With world coordinates you can then use built in API methods to
> convert world coordinates to and from both pixel coordinates and
> geographical (lat, lng) coordinates.
>
> Your google.maps.Map object has a getProjection() method:
>
> http://code.google.com/apis/maps/documentation/javascript/reference.h...
>
> That returns the map's projection, the projection has two methods:
> fromLatLngToPoint() and fromPointToLatLng() that will do these
> conversions for you:
>
> http://code.google.com/apis/maps/documentation/javascript/reference.h...
>
> If your knowledge of javascript is advanced you might even consider
> writing your own 'cartesian projection'.
> The cartesian projection would work directly with cartesian (x, y)
> coordinates with no need to convert to geographical (lat, lng)
> coordinates:
>
> https://groups.google.com/group/google-maps-js-api-v3/search?hl=en&gr...
>
> Martin.
>
> On May 29, 12:26 am, Jason Kaczmarsky <[email protected]> wrote:
>
>
>
>
>
>
>
> > I think I'm on the right track. In the getTile function it creates all
> > the tiles for the map and returns each of them. Obviously each tile is
> > placed accordingly on the page. My idea was to fetch this position in
> > the getTile function and when I view a tile DIV it does show the
> > position on the page. However, the div does not get created in getTile
> > so it has no position yet, it returns it to another function so I
> > cannot access the position. What does getTile return to? I think if I
> > try to access the position from there, I can get it all working.
>
> > On May 28, 7:00 pm, Jason Kaczmarsky <[email protected]> wrote:
>
> > > Alright I got something figured out. I found out how to calculate the
> > > tile at which a certain point it located based on the zoom level. I
> > > still don't understand how I can translate the tile/point position to
> > > workable coordinates.
>
> > > I believe if I can get a particular tile's position relative to the
> > > window position, I can then get the difference and draw a marker based
> > > on that.
>
> > > Don't know if it's obvious, but I'm working in JavaScript and I would
> > > like to draw a div at each point. If I can get the relative position
> > > of a tile to the window, I can absolutely position a div relative to
> > > the tile's X/Y values in the window.
>
> > > On May 28, 6:05 am, John Coryat <[email protected]> wrote:
>
> > > > You can convert a pixel coordinate into a latitude and longitude fairly
> > > > easy. One thing you need to consider. All pixel coordinates are based 
> > > > on a
> > > > particular zoom level. If all your pixel coordinates are assuming one 
> > > > static
> > > > layer, you'll have to figure out what corresponding zoom that 
> > > > represents and
> > > > calculate latitude and longitude based on that.
>
> > > > Here's a Perl module with the tile math.
>
> > > >http://www.usnaviguide.com/google-tiles.htm
>
> > > > Hope that helps.
>
> > > > -John Coryat
>
> > > >http://maps.huge.info
>
> > > >http://www.usnaviguide.com
>
> > > >http://www.zipmaps.net

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