Hi Howard,
Here's the list of the shape files we're loading onto the ServerLayerOverlay as individual ShapeFileFeatureLayers. Except for the country, all the other files are for one state only.
Shape file
Size (MB)
Country
0.15
Major highways
5.9
Secondary highways
19.75
Streets
88.7
Water bodies
25.7
Rail roads
1.6
Parks
8.6
Cities (Points)
0.13
TOTAL
150.53
I built a little caching utility and used your sample code to generate the cache images for the map data above.
ZoomLevelSet levelSet = new ZoomLevelSet();
RectangleShape cacheExtent = new RectangleShape(110, -10, 155, -45); serverLayerOverlay.GenerateCacheImages(levelSet.ZoomLevel01.Scale, cacheExtent, GeographyUnit.DecimalDegree, 256, 256);
//...
//...
serverLayerOverlay.GenerateCacheImages(levelSet.ZoomLevel20.Scale, cacheExtent, GeographyUnit.DecimalDegree, 256, 256);
I started the caching process on Friday afternoon and let it run over the weekend and until this morning (Tuesday). It finished caching upto zoom level 13 this morning and I had to stop it while it was caching zoom level 14. I collected the following stats for the process. The red ones are predicted based on the time taken for zoom level 13. If I had let it continue, it would've finished caching zoom level 20 in the year 2018!
Zoom Level
Start
End
Duration
1
30/10/2009 14:49
30/10/2009 14:49
0:00:00
2
30/10/2009 14:49
30/10/2009 14:49
0:00:00
3
30/10/2009 14:49
30/10/2009 14:49
0:00:00
4
30/10/2009 14:49
30/10/2009 14:49
0:00:00
5
30/10/2009 14:49
30/10/2009 14:49
0:00:00
6
30/10/2009 14:49
30/10/2009 14:50
0:01:00
7
30/10/2009 14:50
30/10/2009 14:51
0:01:00
8
30/10/2009 14:51
30/10/2009 14:54
0:03:00
9
30/10/2009 14:54
30/10/2009 14:59
0:05:00
10
30/10/2009 14:59
30/10/2009 15:23
0:24:00
11
30/10/2009 15:23
30/10/2009 18:09
2:46:00
12
30/10/2009 18:09
31/10/2009 18:26
24:17:00
13
31/10/2009 18:26
3/11/2009 8:53
62:27:00
14
3/11/2009 8:53
10/11/2009 1:29
160:36:15
15
10/11/2009 1:29
27/11/2009 6:31
413:01:45
16
27/11/2009 6:31
10/01/2010 12:42
1062:11:47
17
10/01/2010 12:42
4/05/2010 8:23
2731:40:30
18
4/05/2010 8:23
21/02/2011 1:29
7025:06:37
19
21/02/2011 1:29
14/03/2013 20:08
18066:38:09
20
14/03/2013 20:08
2/07/2018 18:30
46462:22:40
TOTAL
76011:41:43
Red Cells = Predicted
We haven't had to handle such large map data before. We used to work with ECW files in the Desktop Edition. So we're pretty new to the optimisation of shape file loading / caching in the Silverlight Edition. We would appreciate any help / suggestions from you with regards to implementing an efficient client-server Silverlight mapping solution with large map data.
Thanks,
Nirish