Fixed bug 3486 - Can't get HINSTANCE of my window

realitix

SDL2 allows to create widow and to get information through SDL_SysWMinfo.
But it misses something, with Vulkan, you need the HWND and HINSTANCE of the window for Win32 system.
Sadly, SDL2 provides only HWND but not HINSTANCE.

In some context, it can be difficult to get the HINSTANCE, indeed, I'm using pySDL2 (Python) and I can only access properties that SDL2 gives me.
I have to use a dirty trick like that to get the HINSTANCE:  (https://raw.githubusercontent.com/bglgwyng/pyVulkan/master/examples/win32misc.py)

include/SDL_syswm.h

@@ -201,6 +201,7 @@ struct SDL_SysWMinfo
         {
             HWND window;                /**< The window handle */
             HDC hdc;                    /**< The window device context */
+            HINSTANCE hinstance;        /**< The instance handle */
         } win;
 #endif
 #if defined(SDL_VIDEO_DRIVER_WINRT)

src/video/windows/SDL_windowswindow.c

@@ -127,6 +127,7 @@ SetupWindowData(_THIS, SDL_Window * window, HWND hwnd, SDL_bool created)
     data->window = window;
     data->hwnd = hwnd;
     data->hdc = GetDC(hwnd);
+    data->hinstance = (HINSTANCE) GetWindowLongPtr(hwnd, GWLP_HINSTANCE);
     data->created = created;
     data->mouse_button_flags = 0;
     data->videodata = videodata;
@@ -706,6 +707,10 @@ WIN_GetWindowWMInfo(_THIS, SDL_Window * window, SDL_SysWMinfo * info)
             info->info.win.hdc = data->hdc;
         }
 
+        if (versionnum >= SDL_VERSIONNUM(2, 0, 5)) {
+            info->info.win.hinstance = data->hinstance;
+        }
+
         return SDL_TRUE;
     } else {
         SDL_SetError("Application not compiled with SDL %d.%d\n",

src/video/windows/SDL_windowswindow.h

@@ -33,6 +33,7 @@ typedef struct
     HWND hwnd;
     HDC hdc;
     HDC mdc;
+    HINSTANCE hinstance;
     HBITMAP hbm;
     WNDPROC wndproc;
     SDL_bool created;