Set Windows DPI awareness to best possible setting.

QuLogic · QuLogic · commit 8c5b462f69ae · 2021-04-22T23:10:57.000-04:00
diff --git a/src/_c_internal_utils.c b/src/_c_internal_utils.c
@@ -128,7 +128,39 @@ static PyObject*
 mpl_SetDpiAwareness(PyObject* module)
 {
 #ifdef _WIN32
-    SetProcessDPIAware();
+#ifdef _DPI_AWARENESS_CONTEXTS_
+    // These functions and options were added in later Windows 10 updates, so
+    // must be loaded dynamically.
+    typedef BOOL (WINAPI *IsValidDpiAwarenessContext_t)(DPI_AWARENESS_CONTEXT);
+    typedef BOOL (WINAPI *SetProcessDpiAwarenessContext_t)(DPI_AWARENESS_CONTEXT);
+
+    HMODULE user32 = LoadLibrary("user32.dll");
+    IsValidDpiAwarenessContext_t IsValidDpiAwarenessContextPtr =
+        (IsValidDpiAwarenessContext_t)GetProcAddress(
+            user32, "IsValidDpiAwarenessContext");
+    SetProcessDpiAwarenessContext_t SetProcessDpiAwarenessContextPtr =
+        (SetProcessDpiAwarenessContext_t)GetProcAddress(
+            user32, "SetProcessDpiAwarenessContext");
+    if (IsValidDpiAwarenessContextPtr != NULL && SetProcessDpiAwarenessContextPtr != NULL) {
+        if (IsValidDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2)) {
+            // Added in Creators Update of Windows 10.
+            SetProcessDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
+        } else if (IsValidDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE)) {
+            // Added in Windows 10.
+            SetProcessDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE);
+        } else if (IsValidDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_SYSTEM_AWARE)) {
+            // Added in Windows 10.
+            SetProcessDpiAwarenessContextPtr(DPI_AWARENESS_CONTEXT_SYSTEM_AWARE);
+        }
+        FreeLibrary(user32);
+    } else {
+        FreeLibrary(user32);
+#else
+    {
+#endif
+        // Added in Windows Vista.
+        SetProcessDPIAware();
+    }
 #endif
     Py_RETURN_NONE;
 }
@@ -163,8 +195,8 @@ static PyMethodDef functions[] = {
     {"Win32_SetDpiAwareness",
      (PyCFunction)mpl_SetDpiAwareness, METH_NOARGS,
      "Win32_SetDpiAwareness()\n--\n\n"
-     "Set Windows' process DPI awareness to be enabled. On non-Windows\n"
-     "platforms, does nothing."},
+     "Set Windows' process DPI awareness to best option available.\n"
+     "On non-Windows platforms, does nothing."},
     {NULL, NULL}};  // sentinel.
 static PyModuleDef util_module = {
     PyModuleDef_HEAD_INIT, "_c_internal_utils", "", 0, functions, NULL, NULL, NULL, NULL};
