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diff --git a/doc/build_systems/scons-dev.txt b/doc/build_systems/scons-dev.txt deleted file mode 100644 index 9ca072c38c5..00000000000 --- a/doc/build_systems/scons-dev.txt +++ /dev/null @@ -1,193 +0,0 @@ - - Internals of Blenders SCons scripts - =================================== - - Scope - ------ - This document describes the architecture of the SCons scripts for - Blender. An overview of available functionality and how to modify, - extend and maintain the system. - - Audience - -------- - This document is for developers who need to modify the system, - ie. add or remove new libraries, add new arguments for SCons, etc. - - Files and their meaning - ----------------------- - - The main entry point for the build system is the SConstruct-file in - $BLENDERHOME. This file creates the first BlenderEnvironment to work - with, reads in options, and sets up some directory structures. Further - it defines some targets. - - Platform-specific configurations are in $BLENDERHOME/config. The - filenames have the form (platform)-config.py, where platform one of: - - * darwin - * linux - * win32-mingw - * win32-vc - - The user can override options by creating a file - $BLENDERHOME/user-config.py. It can have any option from - (platform)-config.py. Options in this file will override the platform - defaults. - - Much of the actual functionality can be found in the python scripts - in the directory $BLENDERHOME/build_files/scons/tools, with - Blender.py defining the bulk of the functionality. btools.py has some - helper functions, and bcolors.py is for the terminal - colors. mstoolkit.py and crossmingw.py are modules which set up SCons - for the MS VC++ 2003 toolkit and the cross-compile toolset for - compiling Windows binaries on Linux respectively. Note: the - cross-compile doesn't work yet for Blender, but is added in - preparation for having it work in the distant future. - - BlenderEnvironment - ------------------ - - The module Blender.py implements a BlenderEnvironment class, derived - from the SConsEnvironment of SCons. This is done to wrap some often - used functionality. The BlenderEnvironment offers two important - wrappers: BlenderProg() and BlenderLib(). The first one is used to - specify a binary to be built, the second one is used to specify what - static library is built from given sources. - - Build a static library called "somelib". The system handles library - pre- and suffixes automatically, you don't need to bother yourself - with these details: - - env = BlenderEnvironment(ENV = os.environ) # create an environment - env.BlenderLib(libname="somelib", sources=['list.c','with.c','sources.c'], - includes=['/list/with/include/paths', '.', '..'], - defines=['LIST_WITH', 'CPP_DEFINES', 'TO_USE'], - libtype=['blender', 'common'] # this is a list with libtypes. Normally you don't - # need to specify this, but if you encounter linking - # problems you may need this - priority=[10, 20] # Priorities, list as long as libtype, priority per type - compileflags=['/O2'] # List of compile flags needed for this particular library. - # used only in rare cases, like SOLID, qhull and Bullet - ) - - There should be no need to ever add an extra BlenderProg to the - existing ones in SConstruct, see that file for its use, and Blender.py - for its implementation. - - The new system works so that using these wrappers, has all libraries - (and programs) register with a central repository. This means that - adding a new library is as easy as just creating the new SConscript - and making sure that it gets called properly. Linking and such will - then be handled automatically. - - If you want that adding new source files for a certain library - is handled automatically, you can use the Glob() function from - the BlenderEnvironment to create lists of needed files. See - $BLENDERHOME/source/blender/src/SConscript for an example. Keep in - mind that this will add any new file that complies to the rule given - to the Glob() function. There are a few (external) libraries with - which this can't be used, because it'd take files that shouldn't be - compiled, and create subsequentially problems during the linking stage - (like SOLID, qhull, Bullet). - - Linking order and priorities - ---------------------------- - - As shown above, you can give a library a priority in a certain - group. If you need to make sure that a Blender library is linked - before or after another one, you can give it a priority. To debug - the priorities us BF_PRIORITYLIST=1 on the command-line while running - a build. - - % scons BF_PRIORITYLIST=1 - - This will give a list with values suggested by the system. Make - changes to all SConscripts in question to reflect or change the - values given by this command. ALWAYS check this after adding a new - internal, external library or core library, and make sure there are - sane values. You can use large and negative numbers to test with, - but after you've got a working linking order, do change the system - to reflect BF_PRIORITYLIST values. - - Also, if you find that a library needs to be given multiple times to - the linker, you can do that by giving a python list with the names - of the available library types. They are currently: - - B.possible_types = ['core', 'common', 'blender', 'intern', - 'international', 'game', 'game2', - 'player', 'player2', 'system'] - - More groups can be added, but that should be carefully considered, - as it may lead to large-scale changes. The current amount of libraries - should suffice. - - The central repository is utilised in the SConstruct in two - ways. Firstly, it is used to determine the order of all static - libraries to link into the main Blender executable. Secondly, it - is used to keep track of all built binaries and their location, - so that they can be properly copied to BF_INSTALLDIR. - - The libraries can be fetched in their priority order with - create_blender_liblist from Blender.py, see the SConstruct on how - it is used. - - The program repository is the global list program_list from - Blender.py. See SConstruct for its usage. - - - Adding a new option and libraries - --------------------------------- - - Lets say we want to add WITH_BF_NEWLIB, which will - enable or disable a new feature library with sources in - $BLENDERHOME/source/blender/newlib. This 'newlib' needs external - headers from a 3rd party library '3rdparty'. For this we want to - add a set of options BF_3RDPARTY, BF_3RDPARTY_INC, BF_3RDPARTY_LIB, - BF_3RDPARTY_LIBPATH: - - 1) Add all mentiond options to all (platform)-config.py - files. WITH_BF_NEWLIB is a boolean option ('true', 'false'), - the rest are strings with paths and library names. See the - OpenEXR options for example. - - 2) Add all options to the argument checking function - validate_arguments() in btools.py. See again OpenEXR options - for example. - - 3) Add all options to the option reading function read_opts() - in btools.py. See again OpenEXR options for example. All default - values can be empty, as the actual default values are in the - (platform)-config.py files. - - 4) Add BF_3RDPARTY_LIB to the function setup_syslibs() - and BF_3RDPARTY_LIBPATH to the function setup_staticlibs() - in Blender.py - - At this stage we have prepared all option setting and linking needs, - but we still need to add in the compiling of the 'newlib'. - - 5) Create a SConscript in $BLENDERHOME/source/blender/newlib. Look - at ie. $BLENDERHOME/source/blender/src/SConscript for - template. The new SConscript will register the new library - like so: - - env.BlenderLib(libname='newlib', sources=sourcefiles, includes=incs) # the rest of the arguments get defaults = empty lists and values - - 6) Edit $BLENDERHOME/source/blender/SConscript with the following - addition: - - if env['WITH_BF_NEWLIB'] == 1: - SConscript(['newlib/SConscript']) - - After this you can see if this works by trying to build: - - % scons WITH_BF_NEWLIB=1 # build with newlib - % scons WITH_BF_NEWLIB=0 # disable newlib - - This is all what should be needed. Changing the library name doesn't - need changes elsewhere in the system, as it is handled automatically - with the central library repository. - - Enjoy the new system!! - - /Nathan Letwory (jesterKing) |