[MapProxy] New MapProxy 0.8.3 release

[Oliver Tonnhofer]

Hi,

we are proud to announce the release of MapProxy 0.8.3. Read on for
more information.

The latest release is available at:

http://pypi.python.org/pypi/MapProxy

To update within you virtualenv:

$ pip install --no-deps --upgrade MapProxy


Updated documentation is available at:

   http://mapproxy.org/docs/0.8.3/

You will find a new section for proxy.yaml:
http://mapproxy.org/docs/0.8.3/configuration.html#proxy-yaml

There are a few configuration examples (cookbook-style):
http://mapproxy.org/docs/0.8.3/configuration_examples.html

Release information
-------------------

The upcoming 0.8.3 release contains lots of improvements.

Some of the features of the new release are:

Since RC2:
~~~~~~~~~~

- Some bug fixes regarding feature info

- The configured resolutions are sorted

Since RC1:
~~~~~~~~~~

- HTTPS support with certificate verification and HTTP Basic-
  Authentication.

- New `use_direct_from_level` and `use_direct_from_res` options to
  disable caching for high resolutions.

- New `cache_tiles` source for more flexible tile-based sources
  Supports url templates like '/tiles?x=%(x)s&y=%(y)s&level=%(z)s'
  and Quadkeys as used by Bing-Maps. (as suggested by Pascal)

- You can limit the SRS of a source WMS with the `supported_srs`
  option. MapProxy will reproject between cached/requested SRS and
  the supported. This also works with direct layers, i.e. you can
  reproject WMS on-the-fly.

Since 0.8.2
~~~~~~~~~~~

- There is a new seed tool that is far more advanced than existing
  tools. See below for more information.

- There is a new link_single_color_images option for layers. If
  enabled MapProxy will not store tiles that only contain a single
  color as a separate file. With the new option MapProxy stores these
  tiles only once and uses links to this file for every occurrence.
  This can reduce the size of your tile cache if you have larger
  areas with no data (e.g. water areas, areas with no roads, etc.).
  This feature is only available on Unix since Windows has no support
  for symbolic links.

- We have added some performance improvements for servers with
  multiple layers and layers with smaller BBOXs.

- You can configure you own proj4 definition files. For example, if
  you need to tweak some projection parameters.


More information about the new seeding tool:

- Fine control of the seeding area. You are not restricted to BBOX
  anymore and can now load polygons that define the area you want to
  seed. You can load the geometries from text files (WKT) and any
  data source that is supported by OGR (Shapefile, PostGIS, etc.).
  This can reduce the number of tiles to seed dramatically.
  http://mapproxy.org/docs/0.8.3.dev-20100525/seed.html#geographical-extend

- Uses multiple processes for the whole seeding chain (request
  images, split, process, encode and store tiles) for better
  performance on multi-core systems. A new --concurrency option lets
  you define the number of processes.

- New sophisticated seeding strategy. The existing tools (MapProxy,
  TileCache, GeoWebCache) seed from top level to bottom level, from
  north to south, from east to west. This simple strategy works
  against the caches of your operating system and database and
  results in unneeded IO load and thus slower seeding performance. If
  you have large datasets your database will have to drop cached data
  when your seeding area moves to the south. When one level is seeded
  and the seeding tool starts in the north of the next level all data
  cached by you database and operating system is gone and needs to be
  loaded from hard disk again.

  The new seeding tool starts the seeding at the bottom and groups
  the tiles to benefit from the caches of the database and operating
  system. The figure below shows a simple tile pyramid with 3 levels.
  The numbers show the seeding order of every tile.

   level  simple strategy        new strategy

    0            1                    21

    1          2  3                  5 10
               4  5                 15 20

    2        6  7  8  9            1  2  6  7
            10 11 12 13            3  4  8  9
            14 15 16 17           11 12 16 17
            18 19 20 21           13 14 18 19



We hope you will enjoy the new features.
Any comments are welcomed.

Regards,
Oliver

-- 
Oliver Tonnhofer <olt at omniscale.de>
Omniscale - Dominik Helle, Oliver Tonnhofer GbR
Nadorster Str. 60, 26123 Oldenburg
Tel: +49(0)441/9392774-2 (Fax: 9)