[Tutorial] SketchUp Ruby C Extension
-
@unknownuser said:
I have chosen STL C++ Library template ... which produces a C++ dynamic shared library
Wait, are you making a C++ extension instead of C?
I've seen some people making Ruby extensions in C++, but you need to perform some extra steps. Something like
extern "C"
.http://rice.rubyforge.org/
http://www.ruby-forum.com/topic/128668
https://www.google.com/search?hl=en&client=firefox-a&hs=LXd&rls=org.mozilla:en-US:official&q=+site:ruby-forum.com+ruby+c+extension+c%2B%2B&sa=X&ei=7zJXUK62LvLV4QTAvIGgCQ&ved=0CFMQrQIwAw&biw=1600&bih=1096 -
@unknownuser said:
I have chosen STL C++ Library template ... which produces a C++ dynamic shared library (.dylib). I guess it is right type. Unfortunately it does not load with
require "extension"
. Something is still missing.It should according to the description of
Kernel.require()
(1) Try the whole filename:
require("extension.dylib")
(2) Try specifying
Kernel.require("extension_name")
instead of the copy ofrequire()
that is inherited by Object. (Some naughty plugin could have changed it.)(3) Be aware that
require
has undergone changes over the years, to both fix some bugs (early on it pushed filepaths into$LOADED_FEATURES
before it was determined if the files loaded successfully,) and to change the iteration of paths in$LOAD_PATH
(it used to iterate the$LOAD_PATH
array multiple times for each filtype {.rb
,.so
,.o
,.dll
, ...etc.} This was changed later on so it only iterates each directory once.) One of the major SNAFUs with dealing with different Ruby versions for different SketchUp platforms and versions.(4)
require()
has ALWAYS first checked to see if the argument resolves to a valid absolute filepath, and loads that valid file, instead of iterating through the$LOAD_PATH
array. -
@thomthom said:
Wait, are you making a C++ extension instead of C?
Yes. I have finally made it. What a nightmare
Xcode
New Project
Template > "Command Line Tool"!
Enter product name "SX_HelloWorld.bundle"
Type "C++"
The *.c file renamed to *.cpp.
Init_SX_HelloWorld( void ) has to be enclosed in extern "C"extern "C" { // The init function here }
The last line of the code should read:
rb_define_module_function( mSUExtTest, "knock_knock", RUBY_METHOD_FUNC(rb_knock), 0 );
Now the important thing
Build Settings\Linking\Other Linker Flags > -dynamic -bundle -undefined suppress -flat_namespace
Build Settings\Search Paths\Header Search Path > has to point to Ruby headers
Build Settings\Search Paths\Library Search Path > has to point to Ruby compiled libraryI have compiled the extension with LLVM GCC 4.2
-
Where does this macro come from?
RUBY_METHOD_FUNC
-
@thomthom said:
Where does this macro come from?
RUBY_METHOD_FUNC
This sits in ruby.h. Without getting a proper pointer type the code will not compile, since it is C++ now.
#define RUBY_METHOD_FUNC(func) ((VALUE (*)(ANYARGS))func)
-
@dan rathbun said:
Is v4.4 too new to work with such an old Ruby version as 1.8.5-p0 ??
I have compiled the sample extension using dynamic library. My Lion has Ruby 1.8.7 present and this simple example worked just fine.
I am trying to compile Ruby 1.8.5 as a static library now and it looks that with Xcode 4.4, it is next to impossible to get things right. I wish I had Snow Leopard with Xcode 3.2.
-
When recompiling Win32::API under own namespace, do not use -Ox flag.
The -Ox flag from [Compiler Options](http://msdn.microsoft.com/en-US/library/19z1t1wy(v), which creates maximum optimization causes SketchUp to produce a bugsplat right after completion of callback function enumeration.Example:
module My;;CallbackTest EnumWindows = My;;Win32;;API.new('EnumWindows', 'KP', 'I', 'User32') EnumWindowsProc = My;;Win32;;API;;Callback.new('IP', 'I'){ |hwnd, lParam| puts hwnd 1 # continue process } def self.listWindowHandles EnumWindows.call(EnumWindowsProc, nil) # With Compiled $CFLAGS = '-MT -Ox -W4' # SU crashes right after enumation through all parent handles. # With Compiled $CFLAGS = '-MT -W4' # SU works fine, although the size looks ~1.5 KB greater than with the -Ox flag. end end
When compiling Win32::API, I have $CFLAGS = '-MT -W4'
...just sharing some Win32::API compilation experiments
-
Good to know!
I should add some warning about the -Ox flag that it might cause problems - since it's very aggressive optimization.
-
Call for information
I´ve only used a Mac Mini PPC with 10.4 and a Mac Mini Intel with 105 when compiling C Extensions under OSX.
I´m getting all sorts of warning that 10.5 isn´t supported anymore, from Apple and the software. Fair enough.
But what I´d like to know is:
If I update to Montain Lion - what would I need to get SketchUp Ruby C Extensions running?
I take it that the OS Ruby versions is much newer now - and I´d have to link the build to something other than the OS Ruby?Also, when compiling a C Extension under Mountain Lion - how backwards compatible will it be?
-
@thomthom said:
I take it that the OS Ruby versions is much newer now - and I´d have to link the build to something other than the OS Ruby?
No, a Plugin resolves the symbols on load.
@thomthom said:
Also, when compiling a C Extension under Mountain Lion - how backwards compatible will it be?
As much as you ask for it to be: eg -mmacosx-version-min=10.4 will ensure it runs on 10.4 and up.
@thomthom said:
I should add some warning about the -Ox flag that it might cause problems - since it's very aggressive optimization.
Just to correct this. The optimization does not produce 'wrong code' per se. Its that it commonly will remove leaf function stack frames to increase performance, meaning Ruby's GC can't find a reference to a Object and it gets marked for collection. So ensure you keep references and you'll be fine.
-
@adamb said:
No, a Plugin resolves the symbols on load.
Really? But if the OS Ruby is 1.9, and I compile without doing anything. Won't it be compiled for 1.9 only then? Isn't there completely different functions between 1.8 and 1.9?
@adamb said:
As much as you ask for it to be: eg -mmacosx-version-min=10.4 will ensure it runs on 10.4 and up.
Where does this flag go in the compile process? In the MAKEFILE? In the arguments of the make command?
(I'm very green to this.)@adamb said:
Just to correct this. The optimization does not produce 'wrong code' per se. Its that it commonly will remove leaf function stack frames to increase performance, meaning Ruby's GC can't find a reference to a Object and it gets marked for collection. So ensure you keep references and you'll be fine.
Thanks for the clarification.
-
@designingcrime said:
Hey guys, so I finally got a Ruby C extension to compile on both os x and windows and link curllib. I got a lot of help from Luis at the RubyInstaller group and ended up using RubyInstaller and DevKit to link curl and build using the gcc compiler included with devkit.
Here is the extension. Its a modified version of Dana's sketchup downloader, but also included uploading, basic http authentication and ssl certificate checking(all through curl). I provided instructions on how to build on both os x and windows.https://github.com/sunglass/SunglassPlugins/tree/master/SG-SketchupHook/src/Connection%20Manager
Thanks for all your help guys.
Dana - Lets get your Sketchup downloader plugin working.
Link is dead.
-
Just wanted to thank Thomas and everyone else for the contributions in this thread. I tried to get Thomas' Hello World extension working and had no problems at all, thanks to his clear documentation.
My next experiment will be to incorporate SketchUp SDK calls into the Ruby Extension. Has anyone done this? Is it relatively straightforward? Any 'gotchas' that you could warn me about? Thanks
-
Problems already...
I have the SDK .h files installed in the same folder as 'SX_HelloWorld.c'. I'm not sure what to do with the binary files provided with the SDK.I tried to include just one header <slapi/model/model.h> file from the SDK and this was the result.
Feeling clueless...
-
We're actually working on a Hello World example for Visual Studio and Xcode for compiling Ruby C/C++ Extensions for SketchUp. We can expand that (create a work or extra branch) with SLAPI configured as well.
By the way can you post a Gist of your code? You got some syntax errors there that appear to not be related to linking to the correct headers.
-
@tt_su said:
We're actually working on a Hello World example for Visual Studio and Xcode for compiling Ruby C/C++ Extensions for SketchUp. We can expand that (create a work or extra branch) with SLAPI configured as well.
By the way can you post a Gist of your code? You got some syntax errors there that appear to not be related to linking to the correct headers.
Interesting, I was just now doing some research into 'extconf.rb' and I'm starting to think my problem is related to not configuring the location of the .lib and .h files inside of 'extconf.rb' using the 'dir_config' and 'have_library' commands.
BTW, the only difference between my code and your 'hello world' code on bitbucket is that I #included one the SLAPI .h files at the top.
I had assumed (or hoped) that it would be properly linked since I put the files in the same location as the .c file that I was trying to compile.
It goes without saying that I am a complete noob at this.
-
Hi Dale
I looked into this and found that you cannot use Visual Studio's nmake for this as it's C89 - and the SLAPI is written in C99.
It would work if you install the DevKit at Ruby Windows Installer - though I'm still working out some minor quirks. We're preparing some Hello World examples to get started with Ruby C Extensions. Can you hang in there a little bit more?
-
@tt_su said:
Hi Dale
I looked into this and found that you cannot use Visual Studio's nmake for this as it's C89 - and the SLAPI is written in C99.
It would work if you install the DevKit at Ruby Windows Installer - though I'm still working out some minor quirks. We're preparing some Hello World examples to get started with Ruby C Extensions. Can you hang in there a little bit more?
No problem. Thanks for looking into this. I am excited to see the new examples...
-
Good news is that I got the SLAPI example compiling under OSX. I need to test on Windows and clean up the extconf.rb file a little.
-
@tt_su said:
Good news is that I got the SLAPI example compiling under OSX. I need to test on Windows and clean up the extconf.rb file a little.
Cool!
Advertisement