win32: fix detection of the "multimonitor aware" HiDPI mode on Window…

…s 8.1 [p=2724812]
cfillion · Oct 24, 2023 · a3b09e1 · a3b09e1
1 parent 220656b
commit a3b09e1
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Showing 2 changed files with 21 additions and 8 deletions.
diff --git a/src/win32_platform.cpp b/src/win32_platform.cpp
@@ -22,6 +22,7 @@
 #include "win32_window.hpp"
 
 #include <imgui/imgui.h>
+#include <shellscalingapi.h> // GetProcessDpiAwareness for Windows 8.1
 
 // Windows 10 Anniversary Update (1607) and newer
 static FuncImport<decltype(SetThreadDpiAwarenessContext)>
@@ -53,19 +54,31 @@ static bool isPerMonitorDpiAware()
  return *result;
 
  // Windows 10 Anniversary Update (1607) and newer
- static FuncImport<decltype(GetThreadDpiAwarenessContext)>
+ FuncImport<decltype(GetThreadDpiAwarenessContext)>
  _GetThreadDpiAwarenessContext
  { L"User32.dll", "GetThreadDpiAwarenessContext" };
- static FuncImport<decltype(GetAwarenessFromDpiAwarenessContext)>
+ FuncImport<decltype(GetAwarenessFromDpiAwarenessContext)>
  _GetAwarenessFromDpiAwarenessContext
  { L"User32.dll", "GetAwarenessFromDpiAwarenessContext" };
+ if(_GetThreadDpiAwarenessContext && _GetAwarenessFromDpiAwarenessContext) {
+ const DPI_AWARENESS_CONTEXT context { _GetThreadDpiAwarenessContext() };
+ const DPI_AWARENESS awareness { _GetAwarenessFromDpiAwarenessContext(context) };
+ result = awareness == DPI_AWARENESS_PER_MONITOR_AWARE;
+ return *result;
+ }
 
- if(!_GetThreadDpiAwarenessContext || !_GetAwarenessFromDpiAwarenessContext)
- return false;
+ // Windows 8.1
+ FuncImport<decltype(GetProcessDpiAwareness)>
+ _GetProcessDpiAwareness { L"Shcore.dll", "GetProcessDpiAwareness" };
+ if(_GetProcessDpiAwareness) {
+ PROCESS_DPI_AWARENESS awareness {};
+ if(FAILED(_GetProcessDpiAwareness(nullptr, &awareness)))
+ return false;
+ result = awareness == PROCESS_PER_MONITOR_DPI_AWARE;
+ return *result;
+ }
 
- const DPI_AWARENESS_CONTEXT context { _GetThreadDpiAwarenessContext() };
- const DPI_AWARENESS awareness { _GetAwarenessFromDpiAwarenessContext(context) };
- result = awareness == DPI_AWARENESS_PER_MONITOR_AWARE;
+ result = false;
  return *result;
 }
 

diff --git a/src/win32_window.cpp b/src/win32_window.cpp
@@ -26,7 +26,7 @@
 #include "win32_unicode.hpp"
 
 #include <reaper_plugin_secrets.h>
-#include <ShellScalingApi.h> // GetDpiForMonitor
+#include <shellscalingapi.h> // GetDpiForMonitor
 #define GetThemeColor Win32_GetThemeColor // solve conflict with REAPER API
 #include <dwmapi.h> // Dwm* functions for compositing
 #undef GetThemeColor