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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have had a question last year related to performance when
using transparency. Steve mentioned that there are plans to support
feature-level transparency. Do we have any progress at that issue? When can I
count on that feature?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>/Johan<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>___________________________________<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>Johan Hallgren<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>Logica<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>Pelle Bergs backe 3<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>Box 1938, 791 19 Falun<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>Tel (och mobil): 023-547 46 (int: +46-2354746)<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>johan.hallgren@logica.com<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'>http://www.logica.se<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span lang=SV
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>-----Original Message-----<br>
From: UMN MapServer Developers List [mailto:MAPSERVER-DEV@LISTS.UMN.EDU] On
Behalf Of Steve Lime<br>
Sent: den 19 december 2007 20:31<br>
To: MAPSERVER-DEV@LISTS.UMN.EDU<br>
Subject: Re: [UMN_MAPSERVER-DEV] Performance transparency</span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>Hi Johan: I've never quantified the performance hit but it is certainly
expected. Layer-level transparency works like this:<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'> - a temporary image is created to render the transparent layer into,
it is initialized to be completely transparent<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'> - rendering proceeds as normal in the temp image<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'> - the temp image is then "merged" into the base image, so
for every non-transparent pixel in the temp image alpha blending is done and
the base image pixel is modified<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'> - the temporary image is discarded<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>So, the processing time will increase with 1) image size and 2) vector
layer density.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>There are plans to support feature-level transparency but it won't work
in all cases so layer level transparency will remain an option.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>So, the results you are seeing are expected although I can't say if
double is too much or not.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>Steve<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>>>> On 12/19/2007 at 8:49 AM, in message<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'><D93CFEAA72FA764885CC1FDA94A1D89C035462F2@WMRI000166.corp.wmdata.net>,
Hallgren<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>Johan E <jhhal@WMDATA.COM> wrote:<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Hello Friends<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> I a question regarding performance when using a transparent
vectorlayer<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> on top of a rasterlayer. The output is quite large (1400 * 1000
px) and<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> vectordata is a shapefile with polygons. <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> When turning the transparency on the vector layer the performance
goes<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> down quite much. It takes maybe double as long time to produce the
map.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Is there any knowledge about that?<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> /Johan<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> ___________________________________<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Johan Hallgren<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> WM-data, Logica CMG<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Pelle Bergs backe 3<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Box 1938, 791 19 Falun<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> Tel (och mobil): 023-547 46 (int: +46-2354746)<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> johan.e.hallgren@wmdata.com <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <blocked::mailto:johan.e.hallgren@wmdata.com> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> http://www.wmdata.se <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>>
<blocked::https://webaccess.wmdata.com/exchweb/bin/redir.asp?URL=http://<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> www.wmdata.se/> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=3 face="Courier New"><span style='font-size:
12.0pt'>> <o:p></o:p></span></font></p>
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