Should I create an issue ticket in the official bug tracker?
http://code.google.com/p/gmaps-api-issues/

On Mar 10, 6:46 pm, Ben Appleton <[email protected]> wrote:
> Thanks, that's very helpful.  This certainly looks like an API bug; we'll
> look into it.
>
>
>
> On Thu, Mar 11, 2010 at 3:34 AM, Brak <[email protected]> wrote:
> > I've got my simple example ready and here's what it does. The map
> > initializes and sets the default map type to "Tile #s" (CoordMapType)
> > which uses the Euclidean projection, specified earlier, yet draws
> > using the Mercator projection. When you switch to Satellite or Map
> > type, then back to "Tile #s" (CoordMaptType) the projection is drawn
> > properly.
>
> >http://library.ucf.edu/testing/Systems/Library_Maps_Google/Projection...
>
> > Does this look like a my-code problem or a more general API issue?
> > Dun dun dunnnnn!
>
> > On Mar 10, 8:02 am, Brak <[email protected]> wrote:
> > > Thanks Ben. I think I'm starting to think with Portals finally. I
> > > reread the whole discussion along with your new post and am now
> > > understanding the whole issue along with my options. What would you
> > > suggest as a good upscale ratio? Right now, the flat map's coordinates
> > > range from -180 west to 180 east and 90 north to -90 south. Maybe
> > > scale it up to -10 west to 10 east and 10 north to -10 south? What
> > > would make most sense?
>
> > > Sadly I don't presently have a simplified version available at the
> > > moment, but that doesn't mean I can't build one soon. My Maps.js file
> > > really only looks enormous because of all the abandoned commented-out
> > > code. When developing I usually leave old code in for a while, and
> > > delete it when I'm more satisfied with the final product. I'll pull
> > > together a simple(r) version with the custom map, the custom
> > > projection, some example lines, and a built-in alternate map.
>
> > > On Mar 10, 2:59 am, Ben Appleton <[email protected]> wrote:
>
> > > > Wrapping is fundamental to the Maps API, since afterall the world
> > wraps.
> > > >  But you can hide that wrapping by using a small longitudinal range and
> > > > zooming in, so that the wrapping is hidden way offscreen to the
> > left/right.
>
> > > > But I see the issue you describe: your custom projection does not seem
> > to
> > > > take effect until the map type changes away and back again.  Do you
> > have a
> > > > simpler example page that demonstrates this issue?
>
> > > > On Wed, Mar 10, 2010 at 9:17 AM, Brak <[email protected]> wrote:
> > > > > After spending a week and a half scratching my head with various
> > > > > examples I scrapped it and found a new one to work from.
> > > > > Coincidentally it was written by this board's very own Ben Appleton!
>
> > > > > It properly maps the original 256x256 starting tile to top letf:
> > > > > 90,-180 by bottom right: -90,180 lat/lng coordinates. It also
> > provides
> > > > > a way to alter the scale if you so desire. Thanks so much Mr.
> > > > > Appleton! Code included below.
>
> > > > > So now I've got a new problem, now that all my coordinates are mapped
> > > > > and all is good in the projection world. My map (
>
> >http://library.ucf.edu/Administration/Maps/Default_unpublished.asp?de...
> > > > > ) initializes with one of my custom map types, which has been setup
> > to
> > > > > use the custom projection. However, when the map draws for the first
> > > > > time it's still using the default mercator projection. Switching from
> > > > > and back to one of the custom map types invokes the new Euclidean
> > > > > projection, as well as any subsequent time, the way it's supposed to.
> > > > > (Maps JS file:http://library.ucf.edu/Web/Js/Maps.js)
> > > > > It feels like I need to move some of my code around so the map knows
> > > > > to use the new projection instead of the default, but I'm not sure
> > > > > which code needs to move. I've tried moving the relevant code, but it
> > > > > didn't seem to have any effect. (Relevant code being anything that
> > > > > refers to a LatLng() coordinate on the custom maps.)
>
> > > > > I feel like I'm so close to getting it right. I just need a little
> > > > > guidance in the right direction.
>
> > > > > In a separate issue, I don't really understand how to tell the
> > > > > polygons and markers to not wrap, and just stay on the original map
> > > > > region.
>
> > > > > P.S. The computer status polygons on the floormaps have not been
> > > > > remapped since the new flat projection was finished.
>
> > > > > function EuclideanProjection() {
> > > > >        var EUCLIDEAN_RANGE = 256;
> > > > >        this.pixelOrigin_ = new google.maps.Point(EUCLIDEAN_RANGE / 2,
> > > > > EUCLIDEAN_RANGE / 2);
> > > > >        this.pixelsPerLonDegree_ = EUCLIDEAN_RANGE / 360;
> > > > >        this.pixelsPerLonRadian_ = EUCLIDEAN_RANGE / (2 * Math.PI);
> > > > >        this.scaleLat = 2;      // Height - multiplication scale
> > factor
> > > > >        this.scaleLng = 1;      // Width - multiplication scale factor
> > > > >        this.offsetLat = 0;     // Height - direct offset +/-
> > > > >        this.offsetLng = 0;     // Width - direct offset +/-
> > > > > };
>
> > > > > EuclideanProjection.prototype.fromLatLngToPoint = function(latLng,
> > > > > opt_point) {
> > > > >        var point = opt_point || new google.maps.Point(0, 0);
>
> > > > >        var origin = this.pixelOrigin_;
> > > > >        point.x = (origin.x + (latLng.lng() + this.offsetLng ) *
> > > > > this.scaleLng * this.pixelsPerLonDegree_);
> > > > >        // NOTE(appleton): Truncating to 0.9999 effectively limits
> > latitude
> > > > > to
> > > > >        // 89.189.  This is about a third of a tile past the edge of
> > the
> > > > > world tile.
> > > > >        point.y = (origin.y + (-1 * latLng.lat() + this.offsetLat ) *
> > > > > this.scaleLat * this.pixelsPerLonDegree_);
> > > > >        return point;
> > > > > };
>
> > > > > EuclideanProjection.prototype.fromPointToLatLng = function(point) {
> > > > >        var me = this;
>
> > > > >        var origin = me.pixelOrigin_;
> > > > >        var lng = (((point.x - origin.x) / me.pixelsPerLonDegree_) /
> > > > > this.scaleLng) - this.offsetLng;
> > > > >        var lat = ((-1 *( point.y - origin.y) /
> > me.pixelsPerLonDegree_) /
> > > > > this.scaleLat) - this.offsetLat;
> > > > >        return new google.maps.LatLng(lat , lng, true);
> > > > > };
>
> > > > > // Apply it with this
> > > > > myCustomMapType.prototype.projection = new EuclideanProjection();
>
> > > > > On Feb 23, 11:58 am, Brak <[email protected]> wrote:
> > > > > > I too am interested in this functionality for my custom maps. I
> > would
> > > > > > love to build a custom projection for my custom maps that is just
> > 1:1,
> > > > > > but I could live with the LatLng system. My only problem with that
> > > > > > system is that, using the mercator projection, the world wraps and
> > I
> > > > > > need to find a way for my polygons, polylines, markers and
> > infoboxes
> > > > > > to not appear in empty space when zoomed out. I'm assuming that a
> > 1:1
> > > > > > could be a solution to this, but all I can do is guess at this
> > point.
>
> > > > > > I tried fiddling with your example code using it as a basis and I
> > > > > > couldn't get it into a state that Google Maps could make any sense
> > of.
> > > > > > Without any documentation on how the projections are supposed to be
> > > > > > formulated I'm sort of at a loss.
>
> > > > > > Alternatively, can you think of any way to simply disable tiling
> > and
> > > > > > subsequently drawing the overlays outside of the "home tile" (tile
> > 0,0
> > > > > > at zoom level 0)?. I also have a "Center Map" Control button that
> > is
> > > > > > supposed to center the map, but it's expecting a wrapping world too
> > > > > > and will center on a non-existent adjacent tile if the map is
> > scooted
> > > > > > too far left or right.
>
> > > > > > evilC: Did you ever get your projection to work? How is your map
> > > > > > system coming along?
>
> > > > > > On Jan 25, 6:08 pm, Ben Appleton <[email protected]> wrote:
>
> > > > > > > On Tue, Jan 26, 2010 at 9:15 AM, evilC <[email protected]> wrote:
> > > > > > > > I have a reasonable amount of experience with the Google Maps
> > API,
> > > > > but
> > > > > > > > none so far with custom map types and I have been asked to help
> > to
> > > > > > > > make a map of an online game world (http://navemap.com).
>
> > > > > > > > Now from my research, it seems that the smart move would be to
> > > > > > > > properly integrate the game's coordinate system into the map so
> > that
> > > > > > > > things are all accurate. AFAIK, the game world is in effect
> > flat. I
> > > > > am
> > > > > > > > not yet sure on wrapping, there may be e/w wrapping (So it may
> > in
> > > > > > > > effect be a cylinder). I think the origin is in the centre of
> > the
> > > > > map,
> > > > > > > > with negative values for west and north of the origin.
>
> > > > > > > OK.  The Maps API uses latitude/longitude coordinates, which are
> > > > > > > cylindrical.  That is, there is e/w wrapping but no n/s wrapping.
> >  If
> > > > > your
> > > > > > > game coordinates do not wrap e/w, then you can either:
> > > > > > > 1 - Avoid the +/- 180 longitude line by placing your game map
> > from -90
> > > > > to
> > > > > > > +90 longitude.  No-one is likely to pan so far offscreen that
> > they
> > > > > notice
> > > > > > > the world wraps.
> > > > > > > 2 - Or, listen for Map event "center_changed" and if the map pans
> > > > > outside
> > > > > > > -90 to +90 longitude just setCenter() to the nearest point back
> > inside
> > > > > these
> > > > > > > bounds.
>
> > > > > > > So from reading the API documentation, it seems to me that I do
> > not
>
> > > > > > > > want to use a projection? Or if the map insists on one, a plain
> > 1:1
> > > > > > > > conversion from world coordinates to map coordinates?
>
> > > > > > > Yes, a plain 1:1 conversion would do.  So I suggest using
> > > > > > > ImageMapType<
>
> >http://code.google.com/apis/maps/documentation/v3/reference.html#Imag...>
> > > > > > > to
> > > > > > > download your map tiles, and attach a .projection object like:
>
> > > > > > > var myMapType = new ImageMapType(...);
>
> > > > > > > var myProjection = {};
> > > > > > > myProjection.fromLatLngToPoint = function(latLng) {
> > > > > > >   return new
>
> ...
>
> read more »

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