(Breaking) renamed/moved ImGuiConfigFlags_DpiEnableScaleFonts -> ioConfigDpiScaleFonts, ImGuiConfigFlags_DpiEnableScaleViewports -> io.ConfigDpiScaleViewports

backends/imgui_impl_win32.cpp

@@ -23,7 +23,7 @@
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
 //  2025-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
-//  2025-06-02: [Docking] WM_DPICHANGED also apply ImGuiConfigFlags_DpiEnableScaleViewports for main viewport instead of letting it be done by application code.
+//  2025-06-02: [Docking] WM_DPICHANGED also apply io.ConfigDpiScaleViewports for main viewport instead of letting it be done by application code.
 //  2025-04-30: Inputs: Fixed an issue where externally losing mouse capture (due to e.g. focus loss) would fail to claim it again the next subsequent click. (#8594)
 //  2025-03-26: [Docking] Viewports: fixed an issue when closing a window from the OS close button (with io.ConfigViewportsNoDecoration = false) while user code was discarding the 'bool* p_open = false' output from Begin(). Because we allowed the Win32 window to close early, Windows destroyed it and our imgui window became not visible even though user code was still submitting it.
 //  2025-03-10: When dealing with OEM keys, use scancodes instead of translated keycodes to choose ImGuiKey values. (#7136, #7201, #7206, #7306, #7670, #7672, #8468)
@@ -907,7 +907,7 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandlerEx(HWND hwnd, UINT msg, WPA
     case WM_DPICHANGED:
     {
         const RECT* suggested_rect = (RECT*)lParam;
-        if (io.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
+        if (io.ConfigDpiScaleViewports)
             ::SetWindowPos(hwnd, nullptr, suggested_rect->left, suggested_rect->top, suggested_rect->right - suggested_rect->left, suggested_rect->bottom - suggested_rect->top, SWP_NOZORDER | SWP_NOACTIVATE);
         return 0;
     }

docs/CHANGELOG.txt

@@ -60,6 +60,9 @@ Breaking changes:
    - Imgui_ImplSDLGPU3_PrepareDrawData() --> ImGui_ImplSDLGPU3_PrepareDrawData()
 - Internals: RenderTextEllipsis() function removed the 'float clip_max_x' parameter directly
   preceding 'float ellipsis_max_x'. Values were identical for a vast majority of users. (#8387)
+- [Docking] renamed/moved ImGuiConfigFlags_DpiEnableScaleFonts     -> bool io.ConfigDpiScaleFonts.
+- [Docking] renamed/moved ImGuiConfigFlags_DpiEnableScaleViewports -> bool io.ConfigDpiScaleViewports.
+  **Neither of those flags are very useful in current code. They will be useful once we merge font changes.**
 
 Other changes:
 

examples/example_win32_directx11/main.cpp

@@ -61,8 +61,6 @@ int main(int, char**)
     //io.ConfigViewportsNoDefaultParent = true;
     //io.ConfigDockingAlwaysTabBar = true;
     //io.ConfigDockingTransparentPayload = true;
-    //io.ConfigFlags |= ImGuiConfigFlags_DpiEnableScaleFonts;     // FIXME-DPI: Experimental. THIS CURRENTLY DOESN'T WORK AS EXPECTED. DON'T USE IN USER APP!
-    //io.ConfigFlags |= ImGuiConfigFlags_DpiEnableScaleViewports; // FIXME-DPI: Experimental.
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();

imgui.cpp

@@ -440,6 +440,8 @@ CODE
                           - likewise io.MousePos and GetMousePos() will use OS coordinates.
                             If you query mouse positions to interact with non-imgui coordinates you will need to offset them, e.g. subtract GetWindowViewport()->Pos.
 
+ - 2025/06/XX (1.92.0) - Renamed/moved ImGuiConfigFlags_DpiEnableScaleFonts -> bool io.ConfigDpiScaleFonts.
+                       - Renamed/moved ImGuiConfigFlags_DpiEnableScaleViewports -> bool io.ConfigDpiScaleViewports. **Neither of those flags are very useful in current code. They will be useful once we merge font changes.**
  - 2025/05/23 (1.92.0) - Fonts: changed ImFont::CalcWordWrapPositionA() to ImFont::CalcWordWrapPosition()
                             - old:  const char* ImFont::CalcWordWrapPositionA(float scale, const char* text, ....);
                             - new:  const char* ImFont::CalcWordWrapPosition (float size,  const char* text, ....);
@@ -7718,7 +7720,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
 
         WindowSelectViewport(window);
         SetCurrentViewport(window, window->Viewport);
-        window->FontDpiScale = (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts) ? window->Viewport->DpiScale : 1.0f;
+        window->FontDpiScale = g.IO.ConfigDpiScaleFonts ? window->Viewport->DpiScale : 1.0f;
         SetCurrentWindow(window);
         flags = window->Flags;
 
@@ -7863,7 +7865,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
                 // FIXME-DPI
                 //IM_ASSERT(old_viewport->DpiScale == window->Viewport->DpiScale); // FIXME-DPI: Something went wrong
                 SetCurrentViewport(window, window->Viewport);
-                window->FontDpiScale = (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts) ? window->Viewport->DpiScale : 1.0f;
+                window->FontDpiScale = g.IO.ConfigDpiScaleViewports ? window->Viewport->DpiScale : 1.0f;
                 SetCurrentWindow(window);
             }
 
@@ -10924,6 +10926,16 @@ static void ImGui::ErrorCheckNewFrameSanityChecks()
         g.IO.ConfigNavCaptureKeyboard = false;
         g.IO.ConfigFlags &= ~ImGuiConfigFlags_NavNoCaptureKeyboard;
     }
+    if (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts)
+    {
+        g.IO.ConfigDpiScaleFonts = false;
+        g.IO.ConfigFlags &= ~ImGuiConfigFlags_DpiEnableScaleFonts;
+    }
+    if (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
+    {
+        g.IO.ConfigDpiScaleViewports = false;
+        g.IO.ConfigFlags &= ~ImGuiConfigFlags_DpiEnableScaleViewports;
+    }
 
     // Remap legacy clipboard handlers (OBSOLETED in 1.91.1, August 2024)
     if (g.IO.GetClipboardTextFn != NULL && (g.PlatformIO.Platform_GetClipboardTextFn == NULL || g.PlatformIO.Platform_GetClipboardTextFn == Platform_GetClipboardTextFn_DefaultImpl))
@@ -16091,7 +16103,7 @@ static void ImGui::UpdateViewportsNewFrame()
         if (viewport->DpiScale != 0.0f && new_dpi_scale != viewport->DpiScale)
         {
             float scale_factor = new_dpi_scale / viewport->DpiScale;
-            if (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
+            if (g.IO.ConfigDpiScaleViewports)
                 ScaleWindowsInViewport(viewport, scale_factor);
             //if (viewport == GetMainViewport())
             //    g.PlatformInterface.SetWindowSize(viewport, viewport->Size * scale_factor);

imgui.h

@@ -1666,8 +1666,6 @@ enum ImGuiConfigFlags_
     // [BETA] Viewports
     // When using viewports it is recommended that your default value for ImGuiCol_WindowBg is opaque (Alpha=1.0) so transition to a viewport won't be noticeable.
     ImGuiConfigFlags_ViewportsEnable        = 1 << 10,  // Viewport enable flags (require both ImGuiBackendFlags_PlatformHasViewports + ImGuiBackendFlags_RendererHasViewports set by the respective backends)
-    ImGuiConfigFlags_DpiEnableScaleViewports= 1 << 14,  // [BETA: Don't use] FIXME-DPI: Reposition and resize imgui and platform windows when the DpiScale of a viewport changed.
-    ImGuiConfigFlags_DpiEnableScaleFonts    = 1 << 15,  // [BETA: Don't use] FIXME-DPI: Request bitmap-scaled fonts to match DpiScale. This is a very low-quality workaround. The correct way to handle DPI is _currently_ to replace the atlas and/or fonts in the Platform_OnChangedViewport callback, but this is all early work in progress.
 
     // User storage (to allow your backend/engine to communicate to code that may be shared between multiple projects. Those flags are NOT used by core Dear ImGui)
     ImGuiConfigFlags_IsSRGB                 = 1 << 20,  // Application is SRGB-aware.
@@ -1676,6 +1674,8 @@ enum ImGuiConfigFlags_
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
     ImGuiConfigFlags_NavEnableSetMousePos   = 1 << 2,   // [moved/renamed in 1.91.4] -> use bool io.ConfigNavMoveSetMousePos
     ImGuiConfigFlags_NavNoCaptureKeyboard   = 1 << 3,   // [moved/renamed in 1.91.4] -> use bool io.ConfigNavCaptureKeyboard
+    ImGuiConfigFlags_DpiEnableScaleFonts    = 1 << 14,  // [moved/renamed in 1.92.0] -> use bool io.ConfigDpiScaleFonts
+    ImGuiConfigFlags_DpiEnableScaleViewports= 1 << 15,  // [moved/renamed in 1.92.0] -> use bool io.ConfigDpiScaleViewports
 #endif
 };
 
@@ -2373,6 +2373,11 @@ struct ImGuiIO
     bool        ConfigViewportsNoDecoration;    // = true           // Disable default OS window decoration flag for secondary viewports. When a viewport doesn't want window decorations, ImGuiViewportFlags_NoDecoration will be set on it. Enabling decoration can create subsequent issues at OS levels (e.g. minimum window size).
     bool        ConfigViewportsNoDefaultParent; // = false          // Disable default OS parenting to main viewport for secondary viewports. By default, viewports are marked with ParentViewportId = <main_viewport>, expecting the platform backend to setup a parent/child relationship between the OS windows (some backend may ignore this). Set to true if you want the default to be 0, then all viewports will be top-level OS windows.
 
+    // DPI/Scaling options
+    // This may keep evolving during 1.92.x releases. Expect some turbulence.
+    bool        ConfigDpiScaleFonts;            // = false          // [EXPERIMENTAL] Request bitmap-scaled fonts to match DpiScale. This is a very low-quality workaround. The correct way to handle DPI is _currently_ to replace the atlas and/or fonts in the Platform_OnChangedViewport callback, but this is all early work in progress.
+    bool        ConfigDpiScaleViewports;        // = false          // [EXPERIMENTAL] Scale Dear ImGui and Platform Windows when Monitor DPI changes.
+
     // Miscellaneous options
     // (you can visualize and interact with all options in 'Demo->Configuration')
     bool        MouseDrawCursor;                // = false          // Request ImGui to draw a mouse cursor for you (if you are on a platform without a mouse cursor). Cannot be easily renamed to 'io.ConfigXXX' because this is frequently used by backend implementations.

imgui_demo.cpp

@@ -556,11 +556,15 @@ void ImGui::ShowDemoWindow(bool* p_open)
                 ImGui::SameLine(); HelpMarker("Toggling this at runtime is normally unsupported (most platform backends won't refresh the decoration right away).");
                 ImGui::Checkbox("io.ConfigViewportsNoDefaultParent", &io.ConfigViewportsNoDefaultParent);
                 ImGui::SameLine(); HelpMarker("Toggling this at runtime is normally unsupported (most platform backends won't refresh the parenting right away).");
-                //ImGui::CheckboxFlags("ImGuiConfigFlags_DpiEnableScaleViewports", &io.ConfigFlags, ImGuiConfigFlags_DpiEnableScaleViewports);
-                //ImGui::CheckboxFlags("ImGuiConfigFlags_DpiEnableScaleFonts", &io.ConfigFlags, ImGuiConfigFlags_DpiEnableScaleFonts);
                 ImGui::Unindent();
             }
 
+            //ImGui::SeparatorText("DPI/Scaling");
+            //ImGui::Checkbox("io.ConfigDpiScaleFonts", &io.ConfigDpiScaleFonts);
+            //ImGui::SameLine(); HelpMarker("Experimental: Automatically update style.FontScaleDpi when Monitor DPI changes. This will scale fonts but NOT style sizes/padding for now.");
+            //ImGui::Checkbox("io.ConfigDpiScaleViewports", &io.ConfigDpiScaleViewports);
+            //ImGui::SameLine(); HelpMarker("Experimental: Scale Dear ImGui and Platform Windows when Monitor DPI changes.");
+
             ImGui::SeparatorText("Windows");
             ImGui::Checkbox("io.ConfigWindowsResizeFromEdges", &io.ConfigWindowsResizeFromEdges);
             ImGui::SameLine(); HelpMarker("Enable resizing of windows from their edges and from the lower-left corner.\nThis requires ImGuiBackendFlags_HasMouseCursors for better mouse cursor feedback.");
@@ -8209,9 +8213,9 @@ void ImGui::ShowAboutWindow(bool* p_open)
         if (io.ConfigFlags & ImGuiConfigFlags_NoKeyboard)               ImGui::Text(" NoKeyboard");
         if (io.ConfigFlags & ImGuiConfigFlags_DockingEnable)            ImGui::Text(" DockingEnable");
         if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)          ImGui::Text(" ViewportsEnable");
-        if (io.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)  ImGui::Text(" DpiEnableScaleViewports");
-        if (io.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts)      ImGui::Text(" DpiEnableScaleFonts");
         if (io.MouseDrawCursor)                                         ImGui::Text("io.MouseDrawCursor");
+        if (io.ConfigDpiScaleFonts)                                     ImGui::Text("io.ConfigDpiScaleFonts");
+        if (io.ConfigDpiScaleViewports)                                 ImGui::Text("io.ConfigDpiScaleViewports");
         if (io.ConfigViewportsNoAutoMerge)                              ImGui::Text("io.ConfigViewportsNoAutoMerge");
         if (io.ConfigViewportsNoTaskBarIcon)                            ImGui::Text("io.ConfigViewportsNoTaskBarIcon");
         if (io.ConfigViewportsNoDecoration)                             ImGui::Text("io.ConfigViewportsNoDecoration");