I emailed prematurely - I thought the problem was solved with this tweak, but it is not. I think that it is an Openlayers problem rather than a Mapserver one. I'll ask my question on the Openlayers list instead.<br><br>
-David<br><br><div class="gmail_quote">On Thu, Jan 26, 2012 at 11:48 AM, David Quinn <span dir="ltr"><<a href="mailto:daithiquinn@gmail.com">daithiquinn@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<span>Just to follow up with the resolution of this problem, even though it seems to be more on the OpenLayers side. I noticed that I was getting the following error message in Firebug: "NetworkError: 404 Not Found - <a href="http://mysite.com/js_libraries/img/blank.gif" target="_blank">http://mysite.com/js_libraries/img/blank.gif</a>"</span><br>
<br>My openlayers javascript is stored in the '<span>js_libraries' folder. I added a folder 'img' with 'blank.gif', and my problem disappeared. Now, only the queried area is displayed onscreen (but I realize that openlayers is sending a larger query, and replacing the results from Mapserver with a blank gif).<span class="HOEnZb"><font color="#888888"><br>
<br>David<br><br><br></font></span></span><div class="HOEnZb"><div class="h5"><br><div class="gmail_quote">On Wed, Jan 25, 2012 at 7:11 PM, Frank Warmerdam <span dir="ltr"><<a href="mailto:warmerdam@pobox.com" target="_blank">warmerdam@pobox.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>On Wed, Jan 25, 2012 at 3:34 PM, David Quinn <<a href="mailto:daithiquinn@gmail.com" target="_blank">daithiquinn@gmail.com</a>> wrote:<br>
> Just to clarify - so non-square results should be returned without doing<br>
> anything special on the mapserver side?<br>
<br>
</div>David,<br>
<br>
That is my understanding in WMS mode.<br>
<div><br>
>><br>
>><br>
>> But if I were you, I'd start by examining that WMS request is actually<br>
>> being generated and sent to MapServer by OpenLayers and determine<br>
>> if it is doing what it ought to.<br>
><br>
><br>
> This is an example of the html that is returned on screen:<br>
><br>
> <img id="OpenLayersDiv119" style="width: 256px; height: 256px; position:<br>
> relative; opacity: 0.5;" class="olTileImage"<br>
> src="<a href="http://mysite.com/mapserv.cgi?map=roads.map&LAYERS=roads&TRANSPARENT=TRUE&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&STYLES=&FORMAT=image%2Fpng&SRS=EPSG%3A900913&BBOX=-8234561,4996137,-8214993,5015705&WIDTH=256&HEIGHT=256" target="_blank">http://mysite.com/mapserv.cgi?map=roads.map&amp;LAYERS=roads&amp;TRANSPARENT=TRUE&amp;SERVICE=WMS&amp;VERSION=1.1.1&amp;REQUEST=GetMap&amp;STYLES=&amp;FORMAT=image%2Fpng&amp;SRS=EPSG%3A900913&amp;BBOX=-8234561,4996137,-8214993,5015705&amp;WIDTH=256&amp;HEIGHT=256</a>"><br>
><br>
> In this case, I set SIZE 64 64 in my mapfile, but it did not make a<br>
> difference, as 256 seems to be used. The polygon bounds calculated in<br>
> browser using openlayers are as follows: -8254128,4976569,-8215574,4996932<br>
><br>
> I can now see that the problem is due to the entire tile being included, and<br>
> not clipped to the upper extent. But this is strange, as the verticals are<br>
> being clipped ok, as is the lower extent.<br>
<br>
</div>I see that the request getting sent to MapServer is 256x256 and<br>
for a BBOX that is 19568m by 19568m so it seems the problem<br>
is with client side request composition.<br>
<br>
Note that the SIZE keyword in your map file has no effect<br>
on anything when using WMS requests. I believe it is the<br>
default image size when using non-WMS map=mode requests<br>
to MapServer without an explicit size in the request.<br>
<br>
Best regards,<br>
<div><div>--<br>
---------------------------------------+--------------------------------------<br>
I set the clouds in motion - turn up | Frank Warmerdam, <a href="mailto:warmerdam@pobox.com" target="_blank">warmerdam@pobox.com</a><br>
light and sound - activate the windows | <a href="http://pobox.com/%7Ewarmerdam" target="_blank">http://pobox.com/~warmerdam</a><br>
and watch the world go round - Rush | Geospatial Software Developer<br>
</div></div></blockquote></div><br>
</div></div></blockquote></div><br>