[Tilecache] Symbol image transparency problem

[Jez Walters]

Marco,


My sample configuration is a cut-down version of my current 'live' mapfile, which is over 1500 lines long and is split over several files.  I'll see if I can knock up a better example that demonstrates the problem I'm still having.

In the meantime, I tried adding "extension=png" to my tilecache.cfg and adding "format: 'image/png'" to my OpenLayers invocation (as well as flushing the tile cache), but this had no effect.  The comments in the default tilecache.cfg indicate that "extension=png" is the default setting, so I guess adding this wouldn't make a difference anyway?

 
Warm regards,


Jez


-----Original Message-----
From: Marco Nijdam [mailto:marco at west.nl] 
Sent: Tuesday 10 August 2010 13:58
To: Jez Walters
Cc: 'tilecache at openlayers.org'
Subject: RE: [Tilecache] Symbol image transparency problem

Dear Jez,

In your config files, I do not see the underlying topographic layer you
had in your original screen capture.
If you tilecache only the symbols, and the format would not be PNG,
I would expect the background topo layer to be completely hidden.
Since the problem you originally showed was the symbols only to be
non-transparent, but not the room between the symbols,
I'm not sure if we have the complete solution.

Based on the config files you provided, I agree with Jess you need to add
"extension=png" to you tilecache.cfg, in the [ipmap] section.

You also need to request the tiles as PNG, by specifying the format
in the OpenLayers.Layers.WMS constructor, as part of the list of
options in the third argument. So

    layer = new OpenLayers.Layer.WMS("Map",
                                  urls,
                                  {
                                    layers: 'ipmap',
                                    format: 'image/png'
                                  });

Finally you need to remove all existing tiles, to make sure they are
properly generated.

Kind regards,
--
-- Marco Nijdam
--

As quoted from Jez Walters:
> Marco,
>
> It took some work, but I've pared it down to the attached mapfile and
> tilecache.cfg.  For completeness I've enclosed my OpenLayers configuration
> and the image file too, just in case either of these are the culprit.
>
> Any thoughts as to where I'm going wrong - or is it a bug in TileCache?
>
> Jez
>
>
> -----Original Message-----
> From: Marco Nijdam [mailto:marco at west.nl]
> Sent: Monday 9 August 2010 19:56
> To: Jez Walters
> Cc: tilecache at openlayers.org
> Subject: Re: [Tilecache] Symbol image transparency problem
>
> Dear Jez,
>
> Could you please give more information on you setup?
> E.g. mapfile, tilecache.cfg file.
> Are all layers tiled into one tilecache, or are you overlaying multiple
> layers?
>
> Kind regards,
> --
> -- Marco Nijdam
> --
>
> As quoted from Jez Walters:
>>
>> Hello TileCachers,
>>
>> I'm not sure if I posted this question correctly last time, so I'm
>> trying
>> again!  ;-)
>>
>> I'm displaying UK Ordnance Survey MasterMap vector maps using
>> OpenLayers,
>> TileCache and MapServer.  The maps display perfectly when I use just
>> MapServer (
>> http://osgeo-org.1803224.n2.nabble.com/file/n5389483/MapServer.jpg
>> MapServer.jpg  ), as well as when I also use OpenLayers.  However, when
>> I
>> add TileCache to the mix, the various symbol images are no longer
>> transparent (
>> http://osgeo-org.1803224.n2.nabble.com/file/n5389483/TileCache.jpg
>> TileCache.jpg  ).
>>
>> I don't have that much experience of TileCache, so any help/explanation
>> would be most appreciated!
>>
>> Jez
>> --
>> View this message in context:
>> http://osgeo-org.1803224.n2.nabble.com/Symbol-image-transparency-problem-tp5389483p5389483.html
>> Sent from the TileCache mailing list archive at Nabble.com.
>> _______________________________________________
>> Tilecache mailing list
>> Tilecache at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/tilecache



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