Strange map draw issue

[Steve Hall]

Sorry Ed, I must have forgotten to put that part in my email.

Yes, a simple refresh of the same map will, 9 times ot of 10, get rid of 
the garbage.  But then at a random interval it will reappear (but will 
be different garbage).

It's kind of hard for me to "post" the entire app, or allow access, 
right now i'm afraid so I appreciate it may be hard for anyone to help, 
I as just fishing for ideas really!

Thanks,


Steve


Ed McNierney wrote:

> Steve -
>  
> I actually was asking if the output changed if the SAME map was 
> refreshed - don't zoom in, out, or pan, just refresh the image/reload 
> the page.  Does the same image request always return the same image?
>  
>     - Ed
>
> Ed McNierney
> President and Chief Mapmaker
> TopoZone.com / Maps a la carte, Inc.
> 73 Princeton Street, Suite 305
> North Chelmsford, MA  01863
> ed at topozone.com
> (978) 251-4242
>
>
> ------------------------------------------------------------------------
> *From:* Steve Hall [mailto:steve.hall at mercatorgeosystems.co.uk]
> *Sent:* Thursday, September 14, 2006 10:39 AM
> *To:* Ed McNierney
> *Cc:* MAPSERVER-USERS at LISTS.UMN.EDU
> *Subject:* Re: [UMN_MAPSERVER-USERS] Strange map draw issue
>
> Hi Ed,
>
> Thanks for this.  I may check my label columns in the database for 
> NULLs and replace them with an empty string ('') instead.   It looks 
> like a classic 'null' issue doesn't it?
>
> Yup - zoom in, zoom out, pan etc and the garbage generally just 
> disappears, or changes its 'content'.   Often the angle is the same 
> (suspicious) but sometimes not.....  There aren't any features on the 
> angles so i'm not sure if it's a labelling issue or not.  Plus the 
> problem only occurs about 1 in 20 or so map draws so is kind of hard 
> to get a definite problem case.
>
> Checkout these additional ones :
>
> http://demo.mercatorgeosystems.co.uk/tmp/1158243616324003.png
>
> And just to prove it's not all CA....  ;-)
>
> http://demo.mercatorgeosystems.co.uk/tmp/1158244089248601.png
> http://demo.mercatorgeosystems.co.uk/tmp/1158244147717403.png
>
> Thanks Ed,
> Steve
>
>
> Take a
> Ed McNierney wrote:
>
>> Steve -
>>  
>> Well, just about anything in California is a little odd.....
>>  
>> Are you saying that if you simply refresh the image and re-draw the 
>> exact same map you'll see this line of text change?  That's 
>> puzzling.  I would speculate that it's a (garbage) text label for 
>> some garbage feature - there's some feature that's defective in both 
>> location and label (attributes messed up) and that feature is being 
>> labeled.
>>  
>> The first thing I'd try is to eliminate layers from the image, 
>> testing until the garbage goes away.  That could identify the 
>> offending layer; if there are multiple classes in that layer, use the 
>> same system to identify which class it is.  Then see if that says 
>> anything helpful.
>>  
>>     - Ed
>>
>> Ed McNierney
>> President and Chief Mapmaker
>> TopoZone.com / Maps a la carte, Inc.
>> 73 Princeton Street, Suite 305
>> North Chelmsford, MA  01863
>> ed at topozone.com
>> (978) 251-4242
>>
>>
>> ------------------------------------------------------------------------
>> *From:* UMN MapServer Users List 
>> [mailto:MAPSERVER-USERS at LISTS.UMN.EDU] *On Behalf Of *Steve Hall
>> *Sent:* Thursday, September 14, 2006 9:22 AM
>> *To:* MAPSERVER-USERS at LISTS.UMN.EDU
>> *Subject:* [UMN_MAPSERVER-USERS] Strange map draw issue
>>
>> Hi All,
>>
>> I've been using Mapserver for a while now, in a variety of 
>> situations, but am seeing a slightly strange behaviour in one of my 
>> setups.  Basically i'm getting a line of 'garbage' being drawn across 
>> the generated map image.
>>
>> A sample of what I mean is here :
>>
>> http://demo.mercatorgeosystems.co.uk/tmp/1158239461914994.png
>>
>> There is no road feature or other line that should be there, and if I 
>> redraw the map the line of garbage will either disappear or change in 
>> either length or 'content'.  It doesn't appear all the time, but 
>> certainly enough to be annoying.
>>
>> My MapServer version is 4.8.1, running with Apache 1.3.31 on Fedora 
>> Core 4.  I've got several other MapServer based configurations on 
>> this setup and they're all working fine.   The data source in 
>> question is an Oracle 10g (10.1) database which is also used for 
>> other systems and seems fine.....
>>
>> Weird eh?  Any suggestions much appreciated!
>>
>> Thanks,
>> Steve H
>>