[OpenLayers-Users] Re: weird zoom behavior mouse wheel vs double click

[Alessandro Ferrucci]

DOH!

I've figured it out.... I had duplicate controls added to the map.
Here is the code that works fine with the extra controls removed.

Should have looked closer at the code before writing the question...
Thank you very much,
Alessandro Ferrucci

 var map;
            var projectionWGS84 = new OpenLayers.Projection("EPSG:4326");
            var projectionMercator = new OpenLayers.Projection("EPSG:900913");
            // Avoid pink error tiles
            OpenLayers.IMAGE_RELOAD_ATTEMPTS = 3;
            OpenLayers.Util.onImageLoadErrorColor = "transparent";

            function init(){

                var options = {
                    projection: new OpenLayers.Projection("EPSG:900913"),
                    displayProjection: new OpenLayers.Projection("EPSG:4326"),
                    units: "m",
                    numZoomLevels: 20,
                    maxResolution: 156543.0339,
                    maxExtent: new OpenLayers.Bounds(-20037508,
-20037508,20037508, 20037508),
                    controls:[
                            new OpenLayers.Control.Navigation(),
                            new OpenLayers.Control.ArgParser(),
                            new OpenLayers.Control.Attribution(),
                            new OpenLayers.Control.PanZoomBar({
position: new OpenLayers.Pixel(2, 15) }),
                        //    new OpenLayers.Control.Navigation(),
                            new OpenLayers.Control.Scale($('scale')),
                            new OpenLayers.Control.LayerSwitcher(),
                            new OpenLayers.Control.MousePosition(),
                            new OpenLayers.Control.Permalink()
                        ]

            };

                map = new OpenLayers.Map('map',options);
                var googleStreetLayer = new
OpenLayers.Layer.Google("Google Street", {'sphericalMercator':true} );
                map.addLayers([googleStreetLayer]);
           //     map.addControl(new OpenLayers.Control.LayerSwitcher());
//                map.addControl(new OpenLayers.Control.MousePosition());
                var USABounds=new
OpenLayers.Bounds(-124.731,24.956,-66.97,49.372);
                USABounds.transform(projectionWGS84,map.getProjectionObject());
              //  map.zoomToMaxExtent();
                map.zoomToExtent(USABounds);
            }

On Sun, Jul 24, 2011 at 1:06 PM, Alessandro Ferrucci
<alessandroferrucci at gmail.com> wrote:
> Hello,
> I have the following very simple map initialization code for
> OpenLayers with google maps:
>
>  var map;
>            var projectionWGS84 = new OpenLayers.Projection("EPSG:4326");
>            var projectionMercator = new OpenLayers.Projection("EPSG:900913");
>            // Avoid pink error tiles
>            OpenLayers.IMAGE_RELOAD_ATTEMPTS = 3;
>            OpenLayers.Util.onImageLoadErrorColor = "transparent";
>
>            function init(){
>
>                var options = {
>                    projection: new OpenLayers.Projection("EPSG:900913"),
>                    displayProjection: new OpenLayers.Projection("EPSG:4326"),
>                    units: "m",
>                    numZoomLevels: 20,
>                    maxResolution: 156543.0339,
>                    maxExtent: new OpenLayers.Bounds(-20037508,
> -20037508,20037508, 20037508),
>                    controls:[
>                            new OpenLayers.Control.Navigation(),
>                            new OpenLayers.Control.ArgParser(),
>                            new OpenLayers.Control.Attribution(),
>                            new OpenLayers.Control.PanZoomBar({
> position: new OpenLayers.Pixel(2, 15) }),
>                            new OpenLayers.Control.Navigation(),
>                            new OpenLayers.Control.Scale($('scale')),
>                            new OpenLayers.Control.LayerSwitcher(),
>                            new OpenLayers.Control.MousePosition(),
>                            new OpenLayers.Control.Permalink()
>                        ]
>
>            };
>
>                map = new OpenLayers.Map('map',options);
>                var googleStreetLayer = new
> OpenLayers.Layer.Google("Google Street", {'sphericalMercator':true} );
>                map.addLayers([googleStreetLayer]);
>                map.addControl(new OpenLayers.Control.LayerSwitcher());
>                map.addControl(new OpenLayers.Control.MousePosition());
>                var USABounds=new
> OpenLayers.Bounds(-124.731,24.956,-66.97,49.372);
>                USABounds.transform(projectionWGS84,map.getProjectionObject());
>              //  map.zoomToMaxExtent();
>                map.zoomToExtent(USABounds);
>            }
>
> This works fine however, the zoom behavior is weird when I zoom in and
> out using the mouse wheel.
> When I double click on the map the map zooms in 1 tick mark fine,
> however when I use the mouse wheel to zoom in and out, it zooms 2
> ticks at a time.
>
> Has anyone ever encountered this behavior?  Any hints as to why it
> would work as such?
>
> I am using the following OpenLayers
>
> <script src="http://openlayers.org/api/OpenLayers.js"
> type="text/javascript"></script>
>
> Thank you,
> Alessandro Ferrucci
>



-- 
Signed,
Alessandro Ferrucci