关于C++与Python扩展的困惑：如何获取C++值对应的Python值

Question

我想把一些Python代码转换成C++，这样可以提高速度，但这并不是简单地创建一个C++函数然后调用几次那么简单。我不知道怎么把Python中的整数对象转换成C++中的整数。我有一个整数，它是一个对象的属性，我想用这个整数。另外，我还有一些整数，它们在这个对象的一个列表里，我也需要用到。

我想测试用这个函数来创建一个C++扩展：

def setup_framebuffer(surface,flip=False):
   #Create texture if not done already
   if surface.texture is None:
      create_texture(surface)
   #Render child to parent
   if surface.frame_buffer is None:
      surface.frame_buffer = glGenFramebuffersEXT(1)
   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, c_uint(int(surface.frame_buffer)))
   glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, surface.texture, 0)
   glPushAttrib(GL_VIEWPORT_BIT)
   glViewport(0,0,surface._scale[0],surface._scale[1])
   glMatrixMode(GL_PROJECTION)
   glLoadIdentity() #Load the projection matrix
   if flip:
      gluOrtho2D(0,surface._scale[0],surface._scale[1],0)
   else:
      gluOrtho2D(0,surface._scale[0],0,surface._scale[1])

这个函数会调用create_texture，所以我需要把这个函数传递给C++函数，我会通过第三个参数来实现这一点。这是我到目前为止的进展，我在尽量按照Python文档上的信息来做：

#include <Python.h>
#include <GL/gl.h>
static PyMethodDef SpamMethods[] = {
   ...
   {"setup_framebuffer",  setup_framebuffer, METH_VARARGS,"Loads a texture from a Surface object to the OpenGL framebuffer."},
   ...
   {NULL, NULL, 0, NULL}        /* Sentinel */
};
static PyObject * setup_framebuffer(PyObject *self, PyObject *args){
   bool flip;
   PyObject *create_texture, *arg_list,*pyflip,*frame_buffer_id;
   if (!PyArg_ParseTuple(args, "OOO", &surface,&pyflip,&create_texture)){
      return NULL;
   }
   if (PyObject_IsTrue(pyflip) == 1){
      flip = true;
   }else{
      flip = false;
   }
   Py_XINCREF(create_texture);
   //Create texture if not done already
   if(texture == NULL){
      arglist = Py_BuildValue("(O)", surface)
      result = PyEval_CallObject(create_texture, arglist);
      Py_DECREF(arglist);
      if (result == NULL){
         return NULL;
      }
      Py_DECREF(result);
   }
   Py_XDECREF(create_texture);
   //Render child to parent
   frame_buffer_id = PyObject_GetAttr(surface, Py_BuildValue("s","frame_buffer"))
   if(surface.frame_buffer == NULL){
      glGenFramebuffersEXT(1,frame_buffer_id);
   }
   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, surface.frame_buffer));
   glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, surface.texture, 0);
   glPushAttrib(GL_VIEWPORT_BIT);
   glViewport(0,0,surface._scale[0],surface._scale[1]);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity(); //Load the projection matrix
   if (flip){
      gluOrtho2D(0,surface._scale[0],surface._scale[1],0);
   }else{
      gluOrtho2D(0,surface._scale[0],0,surface._scale[1]);
   }
   Py_INCREF(Py_None);
   return Py_None;
}
PyMODINIT_FUNC initcscalelib(void){
   PyObject *module;
   module = Py_InitModule("cscalelib", Methods);
   if (m == NULL){
      return;
   }
}
int main(int argc, char *argv[]){
   /* Pass argv[0] to the Python interpreter */
   Py_SetProgramName(argv[0]);
   /* Initialize the Python interpreter.  Required. */
   Py_Initialize();
   /* Add a static module */
   initscalelib();
}

c# performance optimization data type conversion programming challenges texture creation python extension function calling object properties

关于C++与Python扩展的困惑：如何获取C++值对应的Python值

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