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mapnik/plugins/input/python/build.py

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python: a new plugin to use arbitrary Python as a data source This plugin allows you to write data sources in the Python programming language. This is useful if you want to rapidly prototype a plugin, perform some custom manipulation on data or if you want to bind mapnik to a datasource which is most conveniently accessed through Python. The plugin may be used from the existing mapnik Python bindings or it can embed the Python interpreter directly allowing it to be used from C++, XML or even JavaScript. Mapnik already has excellent Python bindings but they only directly support calling *into* mapnik *from* Python. This forces mapnik and its input plugins to be the lowest layer of the stack. The role of this plugin is to allow mapnik to call *into* Python itself. This allows mapnik to sit as rendering middleware between a custom Python frontend and a custom Python datasource. This increases the utility of mapnik as a component in a larger system. There already exists MemoryDatasource which can be used to dynamically create geometry in Python. It suffers from the problem that it does not allow generating only the geometry which is seen by a particular query. Similarly the entire geometry must exist in memory before rendering can progress. By using a custom iterator object or by using generator expressions this plugin allows geometry to be created on demand and to be destroyed after use. This can have a great impact on memory efficiency. Since geometry is generated on-demand as rendering progresses there can be arbitrarily complex 'cleverness' optimising the geometry generated for a particular query. Obvious examples of this would be generating only geometry within the query bounding box and generating geometry with an appropriate level of detail for the output resolution.
2012-07-19 18:06:44 +00:00
#!/usr/bin/env python
import os
PLUGIN_NAME = 'python'
Import ('plugin_base')
Import ('env')
install_dest = env['MAPNIK_INPUT_PLUGINS_DEST']
plugin_env = plugin_base.Clone()
plugin_sources = Split(
"""
%(PLUGIN_NAME)s_datasource.cpp
%(PLUGIN_NAME)s_featureset.cpp
""" % locals()
)
simplify linking logic in python plugin fixing os x install (where we do not want to link the plugin explicitly to python)
2012-08-06 12:32:41 +00:00
boost_system = 'boost_system%s' % env['BOOST_APPEND']
libraries = ['mapnik',env['BOOST_PYTHON_LIB'],boost_system,env['ICU_LIB_NAME']]
python: a new plugin to use arbitrary Python as a data source This plugin allows you to write data sources in the Python programming language. This is useful if you want to rapidly prototype a plugin, perform some custom manipulation on data or if you want to bind mapnik to a datasource which is most conveniently accessed through Python. The plugin may be used from the existing mapnik Python bindings or it can embed the Python interpreter directly allowing it to be used from C++, XML or even JavaScript. Mapnik already has excellent Python bindings but they only directly support calling *into* mapnik *from* Python. This forces mapnik and its input plugins to be the lowest layer of the stack. The role of this plugin is to allow mapnik to call *into* Python itself. This allows mapnik to sit as rendering middleware between a custom Python frontend and a custom Python datasource. This increases the utility of mapnik as a component in a larger system. There already exists MemoryDatasource which can be used to dynamically create geometry in Python. It suffers from the problem that it does not allow generating only the geometry which is seen by a particular query. Similarly the entire geometry must exist in memory before rendering can progress. By using a custom iterator object or by using generator expressions this plugin allows geometry to be created on demand and to be destroyed after use. This can have a great impact on memory efficiency. Since geometry is generated on-demand as rendering progresses there can be arbitrarily complex 'cleverness' optimising the geometry generated for a particular query. Obvious examples of this would be generating only geometry within the query bounding box and generating geometry with an appropriate level of detail for the output resolution.
2012-07-19 18:06:44 +00:00
link the python plugin to libpython by default
2012-08-22 17:39:49 +00:00
# NOTE: explicit linking to libpython is uneeded on most linux version if the
# python plugin is used by a app in python using mapnik's python bindings
# we explicitly link to libpython here so that this plugin
# can be used from a pure C++ calling application or a different binding language
python_link_flag = '-lpython%s' % env['PYTHON_VERSION']
python: a new plugin to use arbitrary Python as a data source This plugin allows you to write data sources in the Python programming language. This is useful if you want to rapidly prototype a plugin, perform some custom manipulation on data or if you want to bind mapnik to a datasource which is most conveniently accessed through Python. The plugin may be used from the existing mapnik Python bindings or it can embed the Python interpreter directly allowing it to be used from C++, XML or even JavaScript. Mapnik already has excellent Python bindings but they only directly support calling *into* mapnik *from* Python. This forces mapnik and its input plugins to be the lowest layer of the stack. The role of this plugin is to allow mapnik to call *into* Python itself. This allows mapnik to sit as rendering middleware between a custom Python frontend and a custom Python datasource. This increases the utility of mapnik as a component in a larger system. There already exists MemoryDatasource which can be used to dynamically create geometry in Python. It suffers from the problem that it does not allow generating only the geometry which is seen by a particular query. Similarly the entire geometry must exist in memory before rendering can progress. By using a custom iterator object or by using generator expressions this plugin allows geometry to be created on demand and to be destroyed after use. This can have a great impact on memory efficiency. Since geometry is generated on-demand as rendering progresses there can be arbitrarily complex 'cleverness' optimising the geometry generated for a particular query. Obvious examples of this would be generating only geometry within the query bounding box and generating geometry with an appropriate level of detail for the output resolution.
2012-07-19 18:06:44 +00:00
if env['PLATFORM'] == 'Darwin':
if env['PYTHON_DYNAMIC_LOOKUP']:
python_link_flag = '-undefined dynamic_lookup'
elif env['FRAMEWORK_PYTHON']:
if env['FRAMEWORK_SEARCH_PATH']:
python_link_flag = '-F%s -framework Python -Z' % env['FRAMEWORK_SEARCH_PATH']
else:
link_prefix = env['PYTHON_SYS_PREFIX']
if '.framework' in link_prefix:
python_link_flag = '-F%s -framework Python -Z' % os.path.dirname(link_prefix.split('.')[0])
elif '/System' in link_prefix:
python_link_flag = '-F/System/Library/Frameworks/ -framework Python -Z'
else:
python_link_flag = '-F/ -framework Python'
if env['CUSTOM_LDFLAGS']:
linkflags = '%s %s' % (env['CUSTOM_LDFLAGS'], python_link_flag)
else:
linkflags = python_link_flag
plugin_env.Append(CPPPATH = env['PYTHON_INCLUDES'])
TARGET = plugin_env.SharedLibrary(
# the name of the target to build, eg 'sqlite.input'
'../%s' % PLUGIN_NAME,
# prefix - normally none used
SHLIBPREFIX='',
# extension, mapnik expects '.input'
SHLIBSUFFIX='.input',
# list of source files to compile
source=plugin_sources,
# libraries to link to
LIBS=libraries,
# any custom linkflags, eg. LDFLAGS
# in this case CUSTOM_LDFLAGS comes
# from Mapnik's main SConstruct file
# and can be removed here if you do
# not need it
simplify linking logic in python plugin fixing os x install (where we do not want to link the plugin explicitly to python)
2012-08-06 12:32:41 +00:00
LINKFLAGS=linkflags
python: a new plugin to use arbitrary Python as a data source This plugin allows you to write data sources in the Python programming language. This is useful if you want to rapidly prototype a plugin, perform some custom manipulation on data or if you want to bind mapnik to a datasource which is most conveniently accessed through Python. The plugin may be used from the existing mapnik Python bindings or it can embed the Python interpreter directly allowing it to be used from C++, XML or even JavaScript. Mapnik already has excellent Python bindings but they only directly support calling *into* mapnik *from* Python. This forces mapnik and its input plugins to be the lowest layer of the stack. The role of this plugin is to allow mapnik to call *into* Python itself. This allows mapnik to sit as rendering middleware between a custom Python frontend and a custom Python datasource. This increases the utility of mapnik as a component in a larger system. There already exists MemoryDatasource which can be used to dynamically create geometry in Python. It suffers from the problem that it does not allow generating only the geometry which is seen by a particular query. Similarly the entire geometry must exist in memory before rendering can progress. By using a custom iterator object or by using generator expressions this plugin allows geometry to be created on demand and to be destroyed after use. This can have a great impact on memory efficiency. Since geometry is generated on-demand as rendering progresses there can be arbitrarily complex 'cleverness' optimising the geometry generated for a particular query. Obvious examples of this would be generating only geometry within the query bounding box and generating geometry with an appropriate level of detail for the output resolution.
2012-07-19 18:06:44 +00:00
)
# if 'uninstall' is not passed on the command line
# then we actually create the install targets that
# scons will install if 'install' is passed as an arg
if 'uninstall' not in COMMAND_LINE_TARGETS:
env.Install(install_dest, TARGET)
env.Alias('install', install_dest)
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