libosmscout status update october 2011

Here is a list of recent changes to libosmscout:

  • The style sheet has been tuned regarding what is shown on certain zoom levels. This results in general drawing speed improvements while at the same time the map is more readable. We still miss a style sheet especially for mobile devices, which should bring further speed improvements while rendering is optimized for less details on hires screens.
  • Improved clipping leading to faster rendering
  • Improved multipolygon parsing. The “lookup by name” index does directly profit from it, since boundaries are now far better recognized but also some objects not rendered before are now rendered correctly. We still miss real multipolygon drawing including layered drawing and clipping, but this is now planed to be realized real soon now.
  • Added support for low zoom optimizations. Rendering for low zooms is now faster because of special preprocessing during import. Also memory footprint on low zoom should be reduced.
  • Added support for displaying house numbers. Interpolation is still not supported.
  • The tiler demo should now work correctly for all magnifications. Now more clipping artefacts or disappearing objects.
  • Some optimizations reducing file sizes.
  • Initial version of SVG backend (no text yet). The SVG backend create a local stylesheet that allows to adapt the map via an external style sheet.
  • Moved import code into its own library, thus reducing code size and dependencies of the core library. Splitting of backends into their own library is also planned.
  • Redesigned rendering code. preprocessing of rendering data before drawing should now be simpler,allowing advanced algorithms for label placement and similar. First benefit is that streets are now drawn by style sheet priority.
  • Added some more simple example styles.
  • Added API and example for POI lookup.
  • A number of bug fixes, making thing more stable during import and map drawing. libosmscout now compiles under Visual Studio 2005.


On desktop we now have data fetch rates and rendering times for a 800×480 bitmap always below 200ms (each). For high zoom each is far below 100ms.

Next steps:

  • Create a separate library for each backend.
  • Support full multipolygon drawing.
  • Add support for lane drawing.
  • Move from pixels measures in style sheet to mm.
  • Change style sheet syntax to support different style dependent on magnification.
  • Change to a more CSS like style sheet syntax.

As always some screenshots:

Railway network in NRW, Germany
Railway network in NRW, Germany. Red dots show important cities. Light green dots show halts, darker green dots show stations.
motorways in NRW, Germany

motorways in NRW, Germany. Green dots show service stations, red dots show important cities.

Boundaries in NRW, Germany

Boundaries in NRW, Germany. Red dots mark important cities.


3 Responses to “libosmscout status update october 2011”

  1. nwerensteijn Says:

    “Now more clipping artefacts or disappearing objects.”

    i hope you meant ‘no more….’?

  2. nwerensteijn Says:

    ‘Now more clipping artefacts or disappearing objects.’

    I hope you meant: ‘No more…’?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: