如何使用cython将qwidget的HWND(Wind)从python发送到c++

Question

我用python创建了一个qwidget，由它生成的HWND是sip.voidptr。现在，如果我想发送HWND到一个c++代码(通过cython)创建一个表面在vulkan(与vkCreateWin32SurfaceKHR)我应该怎么做?

下面是一段类似于我的代码…

pyandcpp.pyx

cdef extern from 'AppInit.hpp':
cdef cppclass cpClass:
cpClass(int, HWND)# hinstance, hwnd
cdef class pyClass:
cdef cpClass *thisptr
def __cinit__(self, h, ptr):
#print(str(<HWND> ptr))
self.thisptr = new cpClass( h,<HWND> ptr)#int h, void* ptr
print('Done...')

cppfile.cpp

void cpClass::cpClass(int h, HWND ptr) {
createSurdace(h, ptr);
void cpClass::createSurface(int h, HWND ptr) {
//window.createWindowSurface(instance, &surface_);
VkWin32SurfaceCreateInfoKHR create_info = {};
create_info.sType     = VK_STRUCTURE_TYPE_WIN32_SURFACE_CREATE_INFO_KHR;
create_info.hinstance = GetModuleHandle(nullptr);  //tried 0 also
create_info.hwnd      = ptr; //HWND>
if (vkCreateWin32SurfaceKHR(instance, &create_info, nullptr, &surface_)) {
throw std::runtime_error("failed to create surface!");
} else {
throw std::runtime_error("successfull in create surface!");
}
}

Main.py

class HelloTriangleApplication(QWidget):
def __init__(self, parent):
super(HelloTriangleApplication, self).__init__(parent)

self.parent = parent
pyClass(0, self.winId())

我试过<void*>转换sip。Voidptr到CPP Voidptr，但它不起作用。@user1051003在这里问了同样的问题，但是没有答案。

Answer 1

sip.voidptr有一个__int__方法，允许您将地址表示为Python整数。Python整数可以很容易地(在Cython中)转换为C整数，然后转换为指针类型。

比如

from libc.stdint cimport uintptr_t # unsigned int, big enough to hold a pointer
cdef void* convertSipVoidPtrToCVoid(sipObj):
return <void*><uintptr_t>(int(sipObj))