[OpenLayers-Users] Ka-Map layer - kaOrigin?

[Jeff Dege]

Among the things I've been trying, to see if I could get acceptable
performance with the map data I've been working with, is to try the
Ka-Map layer, hoping that the tile caches would make a difference.

I've been unable to get the Ka-Map layer to work, and I've been digging
into why.

I'm working with the release-1.0 code.

I'm declaring the layer as:

	var baseLayer = new OpenLayers.Layer.KaMap("Cities",
			"http://localhost:8080/kamap/tile.php?",
			{ 'map': 'gmap', 'g': 'all', 'i': 'png' },
			'degrees', 
			72 );

and as far as I can see, that's correct.  At least it matches the
instructions at:

 
http://mailman-viper.python-hosting.com/pipermail/users/2006-June/000058
.html

The problem is in KaMap.js - the initialize function takes four
arguments:

    initialize: function(name, url, params, origin) {
        this.kaOrigin = origin;
        var newArguments = new Array();
        newArguments.push(name, url, params);
        OpenLayers.Layer.Grid.prototype.initialize.apply(this,
newArguments);
        this.params = (params ? params : {});
        if (arguments.length > 0 && params) {
            OpenLayers.Util.applyDefaults(
                           this.params, 
                           this.DEFAULT_PARAMS
                           );
        }
    },
When I stick in an alert to print the values, 'name' = "Cities", 'url' =
"http://localhost:8080/kamap/tile.php?", and 'origin' = "degrees".

You can see that 'this.kaOrigin' is assigned "degrees".

But in the next function, 'this.kaOrigin' is referenced as if it had lat
and long member variables:

    addTile:function(bounds,position) {
        var zoom = this.map.getZoom();
        var resolution = this.map.getResolution();
        var scale = 128000000 / Math.pow(2, zoom);
        // 1280000 is an empirical value for a specific tile server, not
yet figured out the
           right way to do this in general.
        // This will probably be based on map.maxResolution.
        var cellSize = new OpenLayers.Size(resolution*this.tileSize.w,
resolution*this.tileSize.h);
        var pX = Math.floor(((bounds.left + this.kaOrigin.lon) /
cellSize.w) * this.tileSize.w);
        var pY = -Math.floor(((bounds.top+this.kaOrigin.lat) /
cellSize.h) * this.tileSize.h);
        var url = this.getFullRequestString(
                      { t: pY, 
                        l: pX,
                        s: scale
                      });

The result is that pX and pY are both assigned values of NaN, and the
URL returned by getFullRequestString() contains "t=NaN&l=NaN", which
results in the KaMap server-side scripts drawing and returning empty
tiles.

>From what I can see, kaOrigin is only referenced in these two locations
- there isn't any other code, anywhere else, that is changing it so that
it contains lat and lon member values.