--- /dev/null
+Nano-X port
+===========
+
+What is it?
+===========
+
+The Nano-X port is based on the wxX11 code, and therefore shares
+almost all of wxX11's code, including the use of the wxUniversal
+widget set. Nano-X is the X-like API of the overall Microwindows
+project, which also has a WIN32 API.
+
+The Microwindows web site is at
+
+ http://microwindows.org/
+
+Nano-X is intended to work on devices with very small amounts
+of memory. wxWindows is quite a large library, so if your
+memory is measured in KB instead of MB you will need to use
+an alternative library, such as FLTK. However, with memory
+capacity increasing all the time, wxWindows could become
+an appropriate embedded GUI solution for many projects.
+Also, it's possible to think of ways to cut wxWindows
+further down to size, such as disabling advanced controls
+or rewriting utility functions. See the section on code size
+below.
+
+An alternative to using Nano-X is to use the standard
+wxX11 port with Tiny-X, which (as I understand it)
+maintains the Xlib API while being sufficiently cut
+down to run on small devices, such as the iPAQ.
+The Familiar Linux Distribution contains Tiny-X. See:
+
+ http://handhelds.org/mailman/listinfo/familiar
+
+Building wxNano-X
+=================
+
+Building is as per the instructions for wxX11 (see readme.txt,
+install.txt) but passing --enable-nanox to configure. You also need
+to export the MICROWIN variable, setting it to the top-level of the
+Microwindows hierarchy. Remember that MICROWIN needs to be defined
+both at configuration time and at subsequent make time, so you
+may find it convenient to put it in your .bash_profile or similar
+file.
+
+Typically, various features in wxWindows will be switched off to
+conserve space. The sample script below calls configure with typical
+options for Nano-X.
+
+Before compiling wxNano-X, you will also need to edit your
+Microwindows 'config' file to match the values hard-coded into
+configure:
+
+ ERASEMOVE=N (otherwise moving windows will look messy)
+ X11=Y
+ OPTIMIZE=N
+ DEBUG=Y
+ VERBOSE=Y
+
+Compile Microwindows by typing 'make' from within the Microwindows src
+directory.
+
+Port notes
+==========
+
+Nano-X has a different API from Xlib, although there
+are many similarities. Instead of changing the wxWindows
+code to reflect Nano-X conventions, a compatibility
+layer has been added, in the form of these files:
+
+include/wx/x11/nanox/X11/Xlib.h ; Xlib compatibility
+include/wx/x11/privx.h ; Useful macros
+src/x11/nanox.c ; Xlib compatibility
+
+There is also an XtoNX.h compatibility header file
+in Microwindows, which we augment with our Xlib.h
+and nanox.c.
+
+Unfortunately it is not always possible, or economical,
+to provide a complete Xlib emulation, so there are
+still wxUSE_NANOX preprocessor directives in the code
+for awkward cases. It may be possible to eliminate
+some, but probably not all, of these in future.
+
+Port Status
+===========
+
+The port is in a very early stage: so far it links
+and a window pops up, but that's about it. (The
+wxX11 port using straight X11 is much more advanced.)
+
+Things to do:
+
+- implement some incomplete compatibility functions
+ in src/x11/nanox.c
+- implement the colour database
+- add mask capability, without which controls won't
+ display properly
+- add further configuration options for disabling
+ code not normally needed in an embedded device
+- optimization and code size reduction
+- figuring out why libstdc++-libc is linked to
+ binaries -- is this done for any C++ program?
+
+Code Size
+=========
+
+Allow about 2.5 MB for a shared wxWindows library, with the
+dynamically linked minimal sample taking about 24KB. If statically
+linked, minimal takes up just over 1MB when stripped. This 1MB
+includes all of wxWindows used in the minimal sample including some of
+the wxUniversal widgets. As application complexity increases,
+the amount of wxWindows code pulled into statically linked
+executables increases, but for large applications, the overhead
+of wxWindows becomes less significant.
+
+Sample sizes:
+-------------
+
+Statically-linked minimal (release): 1,024,272 bytes
+Statically-linked widgets (release): 1,171,568 bytes
+
+Shared lib, stripped (debug): 2,486,716 bytes
+Shared-lib minimal (debug), stripped: 23,896 bytes
+
+Shared lib, stripped (release): 2,315,5004 bytes
+Shared-lib minimal (release), stripped: 23,896 bytes
+(note: the -O flag was not passed to the minimal
+makefile, for some reason)
+
+Strategies for reducing code size
+---------------------------------
+
+- Look at the .o files compiled in a build and check
+ for particularly large files, or files you wouldn't
+ expect to be there in an embedded build.
+- Disable options for features that aren't necessary,
+ for example: image handlers (BMP, JPEG etc.),
+ wxVariant, wxWizard, wxListCtrl, src/univ/themes/gtk.c.
+- Add options to configure.in/setup.h where necessary,
+ for finer-grained configuration.
+- Rewrite functions or classes for alternative stripped-down
+ functionality.
+- Remove unnecessary functionality or obsolete code from
+ wxWindows.
+- Factor out wxWindows code to reduce repetition.
+- Add inlining, remove unnecessary empty functions.
+- Separate code out into individual files so that all of
+ a .o file doesn't get pulled in, just because an app
+ references something else in that file. For example,
+ advanced event types could be separated out.
+ This assumes that the linker isn't clever enough to
+ eliminate redundant functions. The fact that the
+ minimal and widgets samples are very close in size
+ is evidence that gcc is not doing a good job here.
+- Experiment with compiler options.
+- Commercially supported compilers may have better
+ code generation and/or linker optimisation than the
+ one you're currently using.
+
+Sample script for building wxNano-X
+===================================
+
+This script assumes that you will invoke it
+from a build directory under the wxWindows
+top level. So you might type:
+
+% cd wx2
+% mkdir nano-x
+% cd nano-x
+% makewxnanox
+
+If you need to restart compilation without
+reconfiguring, just type 'make' from the same
+directory.
+
+-----------------------------:x----------------------
+
+#!/bin/sh
+# makewxnanox
+
+export MICROWIN=/home/julians/microwindows/microwindows-0.89pre8
+
+#DEBUGFLAGS="--enable-debug --enable-debug_cntxt --disable-optimise"
+DEBUGFLAGS="--disable-debug --disable-debug_cntxt --enable-optimise"
+
+export CONFIGCMD="./configure $DEBUGFLAGS --enable-shared --enable-gui --with-x11 --enable-nanox --enable-log --with-threads --without-sockets --without-odbc --without-libjpeg --without-libtiff --without-png --without-regex --enable-no_exceptions --disable-protocols --disable-ipc --disable-dialupman --disable-apple_ieee --disable-fraction --disable-dynlib --disable-dynamicloader --disable-geometry --disable-fontmap --disable-std_iostreams --disable-filesystem --disable-fs_inet --disable-fs_zip --disable-zipstream --disable-snglinst --disable-mimetype --disable-url --disable-html --disable-constraints --disable-printarch --disable-mdi --disable-postscript --disable-PS-normalized --disable-afmfonts --disable-prologio --disable-resources --disable-dnd --disable-metafile --disable-treelayout --disable-grid --disable-propsheet --disable-splines --disable-joystick --disable-pcx --disable-iff --disable-pnm --disable-tabdialog --disable-newgrid"
+
+echo $CONFIGCMD
+if [ ! -f ./configure ]; then
+ CONFIGCMD=".$CONFIGCMD"
+fi
+
+echo Invoking $CONFIGCMD
+
+rm -f *.cache
+$CONFIGCMD
+
+make
+
+-----------------------------:x----------------------
projects / wxWidgets.git / commitdiff
