Antwort: [UMN_MAPSERVER-USERS] Mapserver crash with gd and antialiasing?

[Justin Schoeman]

Thanks for the help - I see it is a problem in libgd - the clipping must 
be broken as it is trying to renderr off the bottom of the image...

Thanks again,
Justin


Jürgen Link wrote:
> Justin,
> you may want to invoke mapserver on the command line:
> 
>       mapserv "QUERY_STRING=<parameter_list>"
> 
> Replace <parameter_list> by your actual query string from your actual URL
> (i.e. the stuff behind the question mark).
> Output goes to stdout and you'll maybe see some hints.
> You may also want to set the "DEBUG ON" option in your map file to make
> output verbose.
> 
> Jürgen
> --
> Dr. Jürgen Link
> BGS Systemplanung AG
> http://www.bgs-ag.de
> E-Mail juergen.link at bgs-ag.de
> Phone: 02241 166-530
> Fax:   02241 166-680
> Mobile: 0160 97262616
> 
> 
> |---------+------------------------------->
> |         |           Justin Schoeman     |
> |         |           <justin at EXPERTRON.CO|
> |         |           .ZA>                |
> |         |           Gesendet von: UMN   |
> |         |           MapServer Users List|
> |         |           <MAPSERVER-USERS at LIS|
> |         |           TS.UMN.EDU>         |
> |         |                               |
> |         |                               |
> |         |           21.04.2005 15:24    |
> |         |           Bitte antworten an  |
> |         |           Justin Schoeman     |
> |         |                               |
> |---------+------------------------------->
>   >---------------------------------------------------------------------------------------------------------------------------------------------|
>   |                                                                                                                                             |
>   |        An:      MAPSERVER-USERS at LISTS.UMN.EDU                                                                                               |
>   |        Kopie:                                                                                                                               |
>   |        Thema:   [UMN_MAPSERVER-USERS] Mapserver crash with gd and antialiasing?                                                             |
>   >---------------------------------------------------------------------------------------------------------------------------------------------|
> 
> 
> 
> Hi everybody,
> 
> I am trying to use mapserver to render maps.  The basic rendering works
> great, but antialiasing is giving me a lot of trouble.
> 
> After finally figuring out to use TrueColour visuals (RGB instead of PC256)
> for PNG output in libgd (libgd 2.0.33), antialiasing started working
> _but_...
> 
> Some lines cause mapserv (cgi interface) to die (probably a segfault, only
> 'Premature end of script headers: /var/www/cgi-bin/mapserv' gets logged).
> I
> have experienced this with CARTOLINE and ELIPSE styles.  Without
> antialiasing everything works fine.  With antialiasing it sometimes just
> dies...
> 
> I am not sure exactly what lines trigger the problem though.  I know that
> enabling antialiasing on some layers will cause mapserver to die at some
> scale factors... If anybody has any ideas on how to track further, please
> let me know ;-).
> 
> This problem has been verified on mapserver version 4.4.1 and 4.4.2.
> 
> Any help would be greatly appreciated.
> 
> Thanks,
> Justin
>