[MapProxy] New MapProxy 0.8.3rc1 release
olt at omniscale.de
Tue May 25 08:29:52 EDT 2010
there is a new release candidate (RC2) for the upcoming 0.8.3
release of MapProxy.
We missed to make a clear feature freeze since the release of RC1. So
besides some bug fixes it also contains some new features. We'll try
to be more strict on this subject in the future.
Read on for more information.
This release candidate is available at:
To update within your virtualenv:
$ pip install --no-deps --upgrade \
Updated documentation is available at:
You will find a new section for proxy.yaml:
There are a few configuration examples (cookbook-style):
The upcoming 0.8.3 release will contain lots of improvements.
Some of the features of the new release are:
- HTTPS support with certificate verification and HTTP Basic-
- 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.
- 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.
- 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.
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)
More information about the MapProxy