[OpenLayers-Users] Pink tiles displayed with firefox 11 even if tiles are correctly fetched from server. Ok with chromium or older firefox.

[Eric Lemoine]

On Thu, Mar 29, 2012 at 8:39 PM, Arnd Wippermann <arnd.wippermann at web.de> wrote:
> To convince FF11 to display the tiles set tileOptions on the OSM layer:
>
> lyrOSM = new OpenLayers.Layer.OSM("CycleMap",
>    "http://a.tile.opencyclemap.org/cycle/${z}/${x}/${y}.png",
>    {tileOptions : {crossOriginKeyword: null}}
>    );
>
> It should solve your problem.
>
> Perhaps someone can explain, why this is necessary for FF11
> and not for other browsers (bug with FF or incorrect behaviour of the
> others).
>
>
> ...\OpenLayers-2.12-rc1\notes\2.12.md
>
> The `OpenLayers.Tile.Image` class now has a method to get a canvas
> context for processing tiles. Since both OSM and Bing set Access-
> Control-Allow-Origin headers for their tiles, it is possible to
> manipulate a canvas that these tiles were rendered to even if the
> tiles come from a remote origin. Especially when working with custom
> OSM tilesets from servers that do not send Access-Control-Allow-Origin
> headers, it is now necessary to configure the layer with
>
>    tileOptions: {crossOriginKeyword: null}
>
>
> ...\OpenLayers-2.12-rc1\lib\OpenLayers\Layer\OSM.js
>
>    /** APIProperty: tileOptions
>     *  {Object} optional configuration options for <OpenLayers.Tile>
> instances
>     *  created by this Layer. Default is
>     *
>     *  (code)
>     *  {crossOriginKeyword: 'anonymous'}
>     *  (end)
>     *
>     *  When using OSM tilesets other than the default ones, it may be
>     *  necessary to set this to
>     *
>     *  (code)
>     *  {crossOriginKeyword: null}
>     *  (end)
>     *
>     *  if the server does not send Access-Control-Allow-Origin headers.
>     */
>    tileOptions: null,


The discussion <http://lists.osgeo.org/pipermail/openlayers-dev/2012-February/008392.html>
might also help understand the issue.



-- 
Eric Lemoine

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