(Breaking) Move ImGuiWindowFlags_NavFlattened to ImGuiChildFlags_NavFlattened. (#7687)

docs/CHANGELOG.txt

@@ -43,6 +43,11 @@ Breaking changes:
 
 - Removed old nested structure: renaming ImGuiStorage::ImGuiStoragePair type to
   ImGuiStoragePair (simpler for many languages). No significant nested type left.
+- BeginChild: added ImGuiChildFlags_NavFlattened as a replacement for the window
+  flag ImGuiWindowFlags_NavFlattened: the feature only ever made sense for
+  BeginChild() calls anyhow. (#7687) [@cfillion]
+   - old: BeginChild("Name", size, 0, ImGuiWindowFlags_NavFlattened);
+   - new: BeginChild("Name", size, ImGuiChildFlags_NavFlattened, 0)
 - Style: renamed tab colors for clarity and consistency with other changes: (#261, #351)
   - ImGuiCol_TabActive          -> ImGuiCol_TabSelected
   - ImGuiCol_TabUnfocused       -> ImGuiCol_TabDimmed

imgui.cpp

@@ -430,6 +430,9 @@ CODE
  When you are not sure about an old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2024/06/21 (1.90.9) - BeginChild: added ImGuiChildFlags_NavFlattened as a replacement for the window flag ImGuiWindowFlags_NavFlattened: the feature only ever made sense for BeginChild() anyhow.
+                            - old: BeginChild("Name", size, 0, ImGuiWindowFlags_NavFlattened);
+                            - new: BeginChild("Name", size, ImGuiChildFlags_NavFlattened, 0);
  - 2024/06/21 (1.90.9) - io: ClearInputKeys() (first exposed in 1.89.8) doesn't clear mouse data, newly added ClearInputMouse() does.
  - 2024/06/20 (1.90.9) - renamed ImGuiDragDropFlags_SourceAutoExpirePayload to ImGuiDragDropFlags_PayloadAutoExpire.
  - 2024/06/18 (1.90.9) - style: renamed ImGuiCol_TabActive -> ImGuiCol_TabSelected, ImGuiCol_TabUnfocused -> ImGuiCol_TabDimmed, ImGuiCol_TabUnfocusedActive -> ImGuiCol_TabDimmedSelected.
@@ -5533,7 +5536,7 @@ bool ImGui::BeginChildEx(const char* name, ImGuiID id, const ImVec2& size_arg, I
     IM_ASSERT(id != 0);
 
     // Sanity check as it is likely that some user will accidentally pass ImGuiWindowFlags into the ImGuiChildFlags argument.
-    const ImGuiChildFlags ImGuiChildFlags_SupportedMask_ = ImGuiChildFlags_Border | ImGuiChildFlags_AlwaysUseWindowPadding | ImGuiChildFlags_ResizeX | ImGuiChildFlags_ResizeY | ImGuiChildFlags_AutoResizeX | ImGuiChildFlags_AutoResizeY | ImGuiChildFlags_AlwaysAutoResize | ImGuiChildFlags_FrameStyle;
+    const ImGuiChildFlags ImGuiChildFlags_SupportedMask_ = ImGuiChildFlags_Border | ImGuiChildFlags_AlwaysUseWindowPadding | ImGuiChildFlags_ResizeX | ImGuiChildFlags_ResizeY | ImGuiChildFlags_AutoResizeX | ImGuiChildFlags_AutoResizeY | ImGuiChildFlags_AlwaysAutoResize | ImGuiChildFlags_FrameStyle | ImGuiChildFlags_NavFlattened;
     IM_UNUSED(ImGuiChildFlags_SupportedMask_);
     IM_ASSERT((child_flags & ~ImGuiChildFlags_SupportedMask_) == 0 && "Illegal ImGuiChildFlags value. Did you pass ImGuiWindowFlags values instead of ImGuiChildFlags?");
     IM_ASSERT((window_flags & ImGuiWindowFlags_AlwaysAutoResize) == 0 && "Cannot specify ImGuiWindowFlags_AlwaysAutoResize for BeginChild(). Use ImGuiChildFlags_AlwaysAutoResize!");
@@ -5545,6 +5548,8 @@ bool ImGui::BeginChildEx(const char* name, ImGuiID id, const ImVec2& size_arg, I
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
     if (window_flags & ImGuiWindowFlags_AlwaysUseWindowPadding)
         child_flags |= ImGuiChildFlags_AlwaysUseWindowPadding;
+    if (window_flags & ImGuiWindowFlags_NavFlattened)
+        child_flags |= ImGuiChildFlags_NavFlattened;
 #endif
     if (child_flags & ImGuiChildFlags_AutoResizeX)
         child_flags &= ~ImGuiChildFlags_ResizeX;
@@ -5623,7 +5628,7 @@ bool ImGui::BeginChildEx(const char* name, ImGuiID id, const ImVec2& size_arg, I
     const ImGuiID temp_id_for_activation = ImHashStr("##Child", 0, id);
     if (g.ActiveId == temp_id_for_activation)
         ClearActiveID();
-    if (g.NavActivateId == id && !(window_flags & ImGuiWindowFlags_NavFlattened) && (child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY))
+    if (g.NavActivateId == id && !(child_flags & ImGuiChildFlags_NavFlattened) && (child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY))
     {
         FocusWindow(child_window);
         NavInitWindow(child_window, false);
@@ -5649,7 +5654,8 @@ void ImGui::EndChild()
         ImGuiWindow* parent_window = g.CurrentWindow;
         ImRect bb(parent_window->DC.CursorPos, parent_window->DC.CursorPos + child_size);
         ItemSize(child_size);
-        if ((child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY) && !(child_window->Flags & ImGuiWindowFlags_NavFlattened))
+        const bool nav_flattened = (child_window->ChildFlags & ImGuiChildFlags_NavFlattened) != 0;
+        if ((child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY) && !nav_flattened)
         {
             ItemAdd(bb, child_window->ChildId);
             RenderNavHighlight(bb, child_window->ChildId);
@@ -5666,7 +5672,7 @@ void ImGui::EndChild()
             ItemAdd(bb, child_window->ChildId, NULL, ImGuiItemFlags_NoNav);
 
             // But when flattened we directly reach items, adjust active layer mask accordingly
-            if (child_window->Flags & ImGuiWindowFlags_NavFlattened)
+            if (nav_flattened)
                 parent_window->DC.NavLayersActiveMaskNext |= child_window->DC.NavLayersActiveMaskNext;
         }
         if (g.HoveredWindow == child_window)
@@ -6440,7 +6446,7 @@ void ImGui::UpdateWindowParentAndRootLinks(ImGuiWindow* window, ImGuiWindowFlags
         window->RootWindowPopupTree = parent_window->RootWindowPopupTree;
     if (parent_window && !(flags & ImGuiWindowFlags_Modal) && (flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_Popup)))
         window->RootWindowForTitleBarHighlight = parent_window->RootWindowForTitleBarHighlight;
-    while (window->RootWindowForNav->Flags & ImGuiWindowFlags_NavFlattened)
+    while (window->RootWindowForNav->ChildFlags & ImGuiChildFlags_NavFlattened)
     {
         IM_ASSERT(window->RootWindowForNav->ParentWindow != NULL);
         window->RootWindowForNav = window->RootWindowForNav->ParentWindow;
@@ -6536,9 +6542,6 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
     if ((flags & ImGuiWindowFlags_NoInputs) == ImGuiWindowFlags_NoInputs)
         flags |= ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize;
 
-    if (flags & ImGuiWindowFlags_NavFlattened)
-        IM_ASSERT(flags & ImGuiWindowFlags_ChildWindow);
-
     const int current_frame = g.FrameCount;
     const bool first_begin_of_the_frame = (window->LastFrameActive != current_frame);
     window->IsFallbackWindow = (g.CurrentWindowStack.Size == 0 && g.WithinFrameScopeWithImplicitWindow);
@@ -6603,7 +6606,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
     }
 
     // Add to focus scope stack
-    PushFocusScope((flags & ImGuiWindowFlags_NavFlattened) ? g.CurrentFocusScopeId : window->ID);
+    PushFocusScope((window->ChildFlags & ImGuiChildFlags_NavFlattened) ? g.CurrentFocusScopeId : window->ID);
     window->NavRootFocusScopeId = g.CurrentFocusScopeId;
 
     // Add to popup stacks: update OpenPopupStack[] data, push to BeginPopupStack[]
@@ -7199,7 +7202,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             // Child window can be out of sight and have "negative" clip windows.
             // Mark them as collapsed so commands are skipped earlier (we can't manually collapse them because they have no title bar).
             IM_ASSERT((flags & ImGuiWindowFlags_NoTitleBar) != 0);
-            const bool nav_request = (flags & ImGuiWindowFlags_NavFlattened) && (g.NavAnyRequest && g.NavWindow && g.NavWindow->RootWindowForNav == window->RootWindowForNav);
+            const bool nav_request = (window->ChildFlags & ImGuiChildFlags_NavFlattened) && (g.NavAnyRequest && g.NavWindow && g.NavWindow->RootWindowForNav == window->RootWindowForNav);
             if (!g.LogEnabled && !nav_request)
                 if (window->OuterRectClipped.Min.x >= window->OuterRectClipped.Max.x || window->OuterRectClipped.Min.y >= window->OuterRectClipped.Max.y)
                 {
@@ -10189,7 +10192,7 @@ bool ImGui::ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb_arg, ImGu
             window->DC.NavLayersActiveMaskNext |= (1 << window->DC.NavLayerCurrent);
             if (g.NavId == id || g.NavAnyRequest)
                 if (g.NavWindow->RootWindowForNav == window->RootWindowForNav)
-                    if (window == g.NavWindow || ((window->Flags | g.NavWindow->Flags) & ImGuiWindowFlags_NavFlattened))
+                    if (window == g.NavWindow || ((window->ChildFlags | g.NavWindow->ChildFlags) & ImGuiChildFlags_NavFlattened))
                         NavProcessItem();
         }
 
@@ -11678,7 +11681,7 @@ static bool ImGui::NavScoreItem(ImGuiNavItemData* result)
     // When entering through a NavFlattened border, we consider child window items as fully clipped for scoring
     if (window->ParentWindow == g.NavWindow)
     {
-        IM_ASSERT((window->Flags | g.NavWindow->Flags) & ImGuiWindowFlags_NavFlattened);
+        IM_ASSERT((window->ChildFlags | g.NavWindow->ChildFlags) & ImGuiChildFlags_NavFlattened);
         if (!window->ClipRect.Overlaps(cand))
             return false;
         cand.ClipWithFull(window->ClipRect); // This allows the scored item to not overlap other candidates in the parent window

imgui.h

@@ -1044,7 +1044,6 @@ enum ImGuiWindowFlags_
     ImGuiWindowFlags_NoInputs               = ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs | ImGuiWindowFlags_NoNavFocus,
 
     // [Internal]
-    ImGuiWindowFlags_NavFlattened           = 1 << 23,  // [BETA] On child window: share focus scope, allow gamepad/keyboard navigation to cross over parent border to this child or between sibling child windows.
     ImGuiWindowFlags_ChildWindow            = 1 << 24,  // Don't use! For internal use by BeginChild()
     ImGuiWindowFlags_Tooltip                = 1 << 25,  // Don't use! For internal use by BeginTooltip()
     ImGuiWindowFlags_Popup                  = 1 << 26,  // Don't use! For internal use by BeginPopup()
@@ -1054,6 +1053,7 @@ enum ImGuiWindowFlags_
     // Obsolete names
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
     ImGuiWindowFlags_AlwaysUseWindowPadding = 1 << 30,  // Obsoleted in 1.90: Use ImGuiChildFlags_AlwaysUseWindowPadding in BeginChild() call.
+    ImGuiWindowFlags_NavFlattened           = 1 << 31,  // Obsoleted in 1.90.9: Use ImGuiChildFlags_NavFlattened in BeginChild() call.
 #endif
 };
 
@@ -1077,6 +1077,7 @@ enum ImGuiChildFlags_
     ImGuiChildFlags_AutoResizeY             = 1 << 5,   // Enable auto-resizing height. Read "IMPORTANT: Size measurement" details above.
     ImGuiChildFlags_AlwaysAutoResize        = 1 << 6,   // Combined with AutoResizeX/AutoResizeY. Always measure size even when child is hidden, always return true, always disable clipping optimization! NOT RECOMMENDED.
     ImGuiChildFlags_FrameStyle              = 1 << 7,   // Style the child window like a framed item: use FrameBg, FrameRounding, FrameBorderSize, FramePadding instead of ChildBg, ChildRounding, ChildBorderSize, WindowPadding.
+    ImGuiChildFlags_NavFlattened            = 1 << 8,   // Share focus scope, allow gamepad/keyboard navigation to cross over parent border to this child or between sibling child windows.
 };
 
 // Flags for ImGui::InputText()

imgui_demo.cpp

@@ -6851,7 +6851,7 @@ void ImGui::ShowStyleEditor(ImGuiStyle* ref)
                 "Right-click to open edit options menu.");
 
             ImGui::SetNextWindowSizeConstraints(ImVec2(0.0f, ImGui::GetTextLineHeightWithSpacing() * 10), ImVec2(FLT_MAX, FLT_MAX));
-            ImGui::BeginChild("##colors", ImVec2(0, 0), ImGuiChildFlags_Border, ImGuiWindowFlags_AlwaysVerticalScrollbar | ImGuiWindowFlags_AlwaysHorizontalScrollbar | ImGuiWindowFlags_NavFlattened);
+            ImGui::BeginChild("##colors", ImVec2(0, 0), ImGuiChildFlags_Border | ImGuiChildFlags_NavFlattened, ImGuiWindowFlags_AlwaysVerticalScrollbar | ImGuiWindowFlags_AlwaysHorizontalScrollbar);
             ImGui::PushItemWidth(ImGui::GetFontSize() * -12);
             for (int i = 0; i < ImGuiCol_COUNT; i++)
             {
@@ -7251,7 +7251,7 @@ struct ExampleAppConsole
 
         // Reserve enough left-over height for 1 separator + 1 input text
         const float footer_height_to_reserve = ImGui::GetStyle().ItemSpacing.y + ImGui::GetFrameHeightWithSpacing();
-        if (ImGui::BeginChild("ScrollingRegion", ImVec2(0, -footer_height_to_reserve), ImGuiChildFlags_None, ImGuiWindowFlags_HorizontalScrollbar | ImGuiWindowFlags_NavFlattened))
+        if (ImGui::BeginChild("ScrollingRegion", ImVec2(0, -footer_height_to_reserve), ImGuiChildFlags_NavFlattened, ImGuiWindowFlags_HorizontalScrollbar))
         {
             if (ImGui::BeginPopupContextWindow())
             {