Character not found, Expected in: flat namespace

Question

I have a huge gl.pxd file with all the definitions of gl.h , glu.h and glut.h For example, it has the following lines:

 cdef extern from '<OpenGL/gl.h>': ctypedef unsigned int GLenum cdef void glBegin( GLenum mode ) 

I have a window.pyx file that looks like this:

 # Import OpenGL definitions # headers of gl, glu and glut from gl cimport * cdef int argcp cdef char **argv cdef void render_scene(): glClear( GL_COLOR_BUFFER_BIT ) glBegin( GL_TRIANGLES ) glVertex2f( -.5, -.5) glVertex2f( .5, 0 ) glVertex2f( 0, -5. ) glEnd() glutSwapBuffers() cpdef main(): # Initialize GLUT and create Window glutInit( &argcp, argv ) glutInitDisplayMode( GLUT_RGBA | GLUT_DOUBLE ) glutInitWindowPosition( 100, 100 ) glutInitWindowSize( 1280, 720 ) glutCreateWindow( 'My Shiny New Window' ) # Register callbacks glutDisplayFunc( render_scene ) # Enter GLUT event processing cycle glutMainLoop() 

I also have setup.py that looks like this:

 from distutils.core import setup from distutils.extension import Extension from Cython.Distutils import build_ext setup( cmdclass = {'build_ext': build_ext}, ext_modules = [Extension('window', ['window.pyx'])] ) 

Which I call with python3 setup.py build_ext --inplace , and it compiles, and the output is as follows:

 running build_ext cythoning window.pyx to window.c building 'window' extension /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -DNDEBUG -g -O3 -arch i386 -arch x86_64 -I/Library/Frameworks/Python.framework/Versions/3.3/include/python3.3m -c window.c -o build/temp.macosx-10.6-intel-3.3/window.o /usr/bin/clang -bundle -undefined dynamic_lookup -arch i386 -arch x86_64 -g build/temp.macosx-10.6-intel-3.3/window.o -o /Users/petervaro/cygl/window.so 

And I have window_test.py that looks like this:

 import window window.main() 

But if I want to run this python fragment, I got this error:

 Traceback (most recent call last): File "/Users/petervaro/cygl/window_test.py", line 3, in <module> import window ImportError: dlopen(/Users/petervaro/cygl/window.so, 2): Symbol not found: _glBegin Referenced from: /Users/petervaro/cygl/window.so Expected in: flat namespace in /Users/petervaro/cygl/window.so 

My problem is very similar to this: What is the point of this ImportError when importing a .so generated Cython file? - although afaik I do not have an external library, I want to use the built-in OpenGL Lib ...

Oh, and I'm on Mac OS X 10.8.5, Cython 19.2, and Python 3.3. Any help would be appreciated!

Thanks in advance!

Answer 1

Although OpenGL and GLUT are on the system (built-in), I need to connect them as frameworks during the compilation process, so setup.py should look like this:

 from distutils.core import setup from distutils.extension import Extension from Cython.Build import cythonize exts = Extension( name='window', sources=['window.pyx'], extra_link_args=['-framework', 'OpenGL', '-framework', 'GLUT']) setup( name='cygl', ext_modules = cythonize( exts ))