Monthly Archives: July 2011

Spatio-temporal Event Processing with StreamInsight, SQL Server Denali, and Bing Maps – Part 1

Following a recent conversation with Isaac Kunen from the StreamInsight team, I decided that I should find out more about Microsoft’s complex event processing engine. Technology moves so fast that there are probably a hundred topics that I wish I’d … Continue reading

Posted in SQL Server | Tagged , , | 2 Comments

sp_help_spatial_geography_histogram and Indexing geography data in SQL Server Denali

Working with spatial data involves many dark arts, and performance tuning spatial indexes is perhaps the blackest of all of them. Although there are only a few parameters to configure: GRIDS, CELLS_PER_OBJECT, and BOUNDING_BOX, the number of different index combinations … Continue reading

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CaSe-SEnsItIvtY when Handling Multiple Spatial Columns in Safe FME Transformations

Some spatial data formats can store only a single logical set of features. Any given ESRI shapefile, for example, can store only POINTs, LINESTRINGs, or POLYGONs – not a mixture of each type of geometry. What’s more, all of those … Continue reading

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Determining the Geographic Extent of Spatial Features in a SQL Server Table

I’ve been using the SQL Server Denali CTP(s) for just over 6 months now. As a result, I’ve become accustomed to some of the new features and forget that they aren’t generally available in production environments yet… it always comes … Continue reading

Posted in SQL Server | Tagged , , | 4 Comments

Deleting Blank Tiles. In a Dangerous Way.

Creating raster tilesets almost invariably leads to the creation of some blank tiles – covering those areas of space where no features were present in the underlying dataset. Depending on the image format you use for your tiles, and the … Continue reading

Posted in Bing Maps, Spatial | Tagged , , , | 1 Comment

Creating Hill Shaded Tile Overlays

The default Bing Maps road style uses a “hillshade” effect to give an impression of underlying terrain. It’s a relatively subtle, but surprisingly powerful technique to enhance the appearance of map layers, as demonstrated by comparing the following two tiles: … Continue reading

Posted in Bing Maps, Spatial | Tagged , , , , | 4 Comments

Rendering Text Labels with Custom Fonts in Mapnik

The default font family used for rendering text labels on maps created by Mapnik (and the one shipped with it) is Deja Vu. Deja Vu Sans Book is a pretty nice font, and can be seen, for example, in all … Continue reading

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