Overlap: IsItemHovered: Changed behavior to return false when queryin…

…g an item using AllowOverlap mode. Added ImGuiHoveredFlags_AllowWhenOverlappedByItem, ImGuiHoveredFlags_AllowWhenOverlappedByWindow., (#6512, #3909, #517)

docs/CHANGELOG.txt

@@ -48,6 +48,8 @@ Breaking changes:
     and relied on ambiguously defined design. Use 'SetNextItemAllowOverlap()' before item instead.
   - Renamed 'ImGuiTreeNodeFlags_AllowItemOverlap' to 'ImGuiTreeNodeFlags_AllowOverlap'.
   - Renamed 'ImGuiSelectableFlags_AllowItemOverlap' to 'ImGuiSelectableFlags_AllowOverlap'
+  - IsItemHovered: Changed behavior to return false when querying an item using AllowOverlap mode
+    which is being overlapped. Added ImGuiHoveredFlags_AllowWhenOverlappedByItem. (#6512, #3909, #517)
   - Kept redirecting enums (will obsolete).
 
 Other changes:
@@ -72,6 +74,9 @@ Other changes:
     isn't covered as much. (Match offset for drag and drop tooltips)
   - IsItemHovered: Tweaked default value of style.HoverDelayNormal from 0.30 to 0.40,
     Tweaked default value of style.HoverDelayShort from 0.10 to 0.15. (#1485)
+  - IsItemHovered: Added _AllowWhenOverlappedByWindow to ignore window-overlap only.
+    Option ImGuiHoveredFlags_AllowWhenOverlapped now expand into a combination of both
+    _AllowWhenOverlappedByWindow + _AllowWhenOverlappedByItem, matching old behavior.
 - Overlapping items: (#6512, #3909, #517)
   - Selectable, TreeNode: When using ImGuiSelectableFlags_AllowOverlap/ImGuiTreeNodeFlags_AllowOverlap
     and holding item held, overlapping widgets won't appear as hovered. (#6512, #3909)

imgui.cpp

@@ -399,6 +399,7 @@ CODE
 
  - 2023/06/28 (1.89.7) - overlapping items: obsoleted 'SetItemAllowOverlap()' (called after item) in favor of calling 'SetNextItemAllowOverlap()' (called before item). 'SetItemAllowOverlap()' didn't and couldn't work reliably since 1.89 (2022-11-15).
  - 2023/06/28 (1.89.7) - overlapping items: renamed 'ImGuiTreeNodeFlags_AllowItemOverlap' to 'ImGuiTreeNodeFlags_AllowOverlap', 'ImGuiSelectableFlags_AllowItemOverlap' to 'ImGuiSelectableFlags_AllowOverlap'. Kept redirecting enums (will obsolete).
+ - 2023/06/28 (1.89.7) - overlapping items: IsItemHovered() now by default return false when querying an item using AllowOverlap mode which is being overlapped. Use ImGuiHoveredFlags_AllowWhenOverlappedByItem to revert to old behavior.
  - 2023/06/20 (1.89.7) - moved io.HoverDelayShort/io.HoverDelayNormal to style.HoverDelayShort/style.HoverDelayNormal. As the fields were added in 1.89 and expected to be left unchanged by most users, or only tweaked once during app initialization, we are exceptionally accepting the breakage.
  - 2023/05/30 (1.89.6) - backends: renamed "imgui_impl_sdlrenderer.cpp" to "imgui_impl_sdlrenderer2.cpp" and "imgui_impl_sdlrenderer.h" to "imgui_impl_sdlrenderer2.h". This is in prevision for the future release of SDL3.
  - 2023/05/22 (1.89.6) - listbox: commented out obsolete/redirecting functions that were marked obsolete more than two years ago:
@@ -3983,12 +3984,13 @@ bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
         // to use IsItemHovered() after EndChild() itself. Until a solution is found I believe reverting to the test from 2017/09/27 is safe since this was
         // the test that has been running for a long while.
         if (g.HoveredWindow != window && (status_flags & ImGuiItemStatusFlags_HoveredWindow) == 0)
-            if ((flags & ImGuiHoveredFlags_AllowWhenOverlapped) == 0)
+            if ((flags & ImGuiHoveredFlags_AllowWhenOverlappedByWindow) == 0)
                 return false;
 
         // Test if another item is active (e.g. being dragged)
+        const ImGuiID id = g.LastItemData.ID;
         if ((flags & ImGuiHoveredFlags_AllowWhenBlockedByActiveItem) == 0)
-            if (g.ActiveId != 0 && g.ActiveId != g.LastItemData.ID && !g.ActiveIdAllowOverlap && g.ActiveId != window->MoveId)
+            if (g.ActiveId != 0 && g.ActiveId != id && !g.ActiveIdAllowOverlap && g.ActiveId != window->MoveId)
                 return false;
 
         // Test if interactions on this window are blocked by an active popup or modal.
@@ -4002,8 +4004,14 @@ bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
 
         // Special handling for calling after Begin() which represent the title bar or tab.
         // When the window is skipped/collapsed (SkipItems==true) that last item will never be overwritten so we need to detect the case.
-        if (g.LastItemData.ID == window->MoveId && window->WriteAccessed)
+        if (id == window->MoveId && window->WriteAccessed)
             return false;
+
+        // Test if using AllowOverlap and overlapped
+        if ((g.LastItemData.InFlags & ImGuiItemflags_AllowOverlap) && id != 0)
+            if ((flags & ImGuiHoveredFlags_AllowWhenOverlappedByItem) == 0)
+                if (g.HoveredIdPreviousFrame != g.LastItemData.ID)
+                    return false;
     }
 
     // Handle hover delay

imgui.h

@@ -1296,9 +1296,11 @@ enum ImGuiHoveredFlags_
     ImGuiHoveredFlags_AllowWhenBlockedByPopup       = 1 << 5,   // Return true even if a popup window is normally blocking access to this item/window
     //ImGuiHoveredFlags_AllowWhenBlockedByModal     = 1 << 6,   // Return true even if a modal popup window is normally blocking access to this item/window. FIXME-TODO: Unavailable yet.
     ImGuiHoveredFlags_AllowWhenBlockedByActiveItem  = 1 << 7,   // Return true even if an active item is blocking access to this item/window. Useful for Drag and Drop patterns.
-    ImGuiHoveredFlags_AllowWhenOverlapped           = 1 << 8,   // IsItemHovered() only: Return true even if the position is obstructed or overlapped by another WINDOW.
-    ImGuiHoveredFlags_AllowWhenDisabled             = 1 << 9,   // IsItemHovered() only: Return true even if the item is disabled
-    ImGuiHoveredFlags_NoNavOverride                 = 1 << 10,  // IsItemHovered() only: Disable using gamepad/keyboard navigation state when active, always query mouse
+    ImGuiHoveredFlags_AllowWhenOverlappedByItem     = 1 << 8,   // IsItemHovered() only: Return true even if the item uses AllowOverlap mode and is overlapped by another hoverable item.
+    ImGuiHoveredFlags_AllowWhenOverlappedByWindow   = 1 << 9,   // IsItemHovered() only: Return true even if the position is obstructed or overlapped by another window.
+    ImGuiHoveredFlags_AllowWhenDisabled             = 1 << 10,  // IsItemHovered() only: Return true even if the item is disabled
+    ImGuiHoveredFlags_NoNavOverride                 = 1 << 11,  // IsItemHovered() only: Disable using gamepad/keyboard navigation state when active, always query mouse
+    ImGuiHoveredFlags_AllowWhenOverlapped           = ImGuiHoveredFlags_AllowWhenOverlappedByItem | ImGuiHoveredFlags_AllowWhenOverlappedByWindow,
     ImGuiHoveredFlags_RectOnly                      = ImGuiHoveredFlags_AllowWhenBlockedByPopup | ImGuiHoveredFlags_AllowWhenBlockedByActiveItem | ImGuiHoveredFlags_AllowWhenOverlapped,
     ImGuiHoveredFlags_RootAndChildWindows           = ImGuiHoveredFlags_RootWindow | ImGuiHoveredFlags_ChildWindows,
 

imgui_demo.cpp

@@ -2430,7 +2430,8 @@ static void ShowDemoWindowWidgets()
             "IsItemHovered() = %d\n"
             "IsItemHovered(_AllowWhenBlockedByPopup) = %d\n"
             "IsItemHovered(_AllowWhenBlockedByActiveItem) = %d\n"
-            "IsItemHovered(_AllowWhenOverlapped) = %d\n"
+            "IsItemHovered(_AllowWhenOverlappedByItem) = %d\n"
+            "IsItemHovered(_AllowWhenOverlappedByWindow) = %d\n"
             "IsItemHovered(_AllowWhenDisabled) = %d\n"
             "IsItemHovered(_RectOnly) = %d\n"
             "IsItemActive() = %d\n"
@@ -2449,7 +2450,8 @@ static void ShowDemoWindowWidgets()
             ImGui::IsItemHovered(),
             ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup),
             ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem),
-            ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenOverlapped),
+            ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenOverlappedByItem),
+            ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenOverlappedByWindow),
             ImGui::IsItemHovered(ImGuiHoveredFlags_AllowWhenDisabled),
             ImGui::IsItemHovered(ImGuiHoveredFlags_RectOnly),
             ImGui::IsItemActive(),