Inputs: added wip/internal Input Owner system. (#456, #2637, #2620, #2891, #3370, #4828, #5108, #5242, #5641)

- Added SetKeyOwner(), SetItemKeyOwner(), TestKeyOwner().
- Added new IsKeyXXX IsMouseXXX functions with ImGuID owner_id and flags.
- Obsoleted SetItemUsingMouseWheel(). (#2891)
- Removed IsKeyPresseedEx() which was a recent internal addition 2022-07-08 deemed to be temporary exactly for this.
- Added ImGuiButtonFlags_NoSetKeyOwner, ImGuiButtonFlags_NoTestKeyOwner
- Added ImGuiSelectableFlags_NoSetKeyOwner.
- Added ImGuiInputFlags_LockThisFrame, ImGuiInputFlags_LockUntilRelease for for SetKeyOwner(), SetItemKeyOwner().
- Added ImGuiInputFlags_CondXXX values for SetItemKeyOwner().

docs/CHANGELOG.txt

@@ -107,6 +107,17 @@ Other Changes:
 - Popups & Modals: fixed nested Begin() being erroneously input-inhibited. While it is
   unusual, you can nest a Begin() inside a popup or modal, it is occasionally useful to
   achieve certains things (e.g. some ways to implement suggestion popup #718, #4461).
+- Inputs: Standard widgets now claim for key/button ownership and test for them.
+  - Fixes scenario where e.g. a Popup with a Selectable() reacting on mouse down
+    (e.g. double click) closes, and behind it is another window with an item reacting
+    on mouse up. Previously this would lead to both items reacting, now the item in the
+    window behind won't react on the mouse up since the mouse button ownership has already
+    been claimed earlier.
+  - Internals: There are MANY more aspects to this changes. Added experimental/internal APIs
+    to allow handling input/shorting routing and key ownership. Things will be moved into
+    public APIs over time. For now this release is a way to test the solidity of underlying
+    systems while letting early adopters adopters toy with internals.
+    (#456, #2637, #2620, #2891, #3370, #3724, #4828, #5108, #5242, #5641)
 - Scrolling: Tweak mouse-wheel locked window timer so it is shorter but also gets reset
   whenever scrolling again (#2604).
 - Scrolling: Mitigated issue where multi-axis mouse-wheel inputs (usually from touch pad
@@ -116,7 +127,7 @@ Other Changes:
 - InputText: numerical fields automatically accept full-width characters (U+FF01..U+FF5E)
   by converting them to half-width (U+0021..U+007E).
 - InputText: added ImGuiInputTextFlags_EscapeClearsAll flag: first press on Escape clears
-  text if any, second press deactivate the InputText(). (#5688)
+  text if any, second press deactivate the InputText(). (#5688, #2620)
 - InputText: added support for shift+click style selection. (#5619) [@procedural]
 - InputText: clarified that callbacks cannot modify buffer when using the ReadOnly flag.
 - InputText: fixed minor one-frame selection glitch when reverting with Escape.

imgui.cpp

@@ -3546,7 +3546,7 @@ void ImGui::SetActiveID(ImGuiID id, ImGuiWindow* window)
     // Clear declaration of inputs claimed by the widget
     // (Please note that this is WIP and not all keys/inputs are thoroughly declared by all widgets yet)
     g.ActiveIdUsingNavDirMask = 0x00;
-    g.ActiveIdUsingKeyInputMask.ClearAllBits();
+    g.ActiveIdUsingAllKeyboardKeys = false;
 #ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
     g.ActiveIdUsingNavInputMask = 0x00;
 #endif
@@ -3562,7 +3562,6 @@ void ImGui::SetHoveredID(ImGuiID id)
     ImGuiContext& g = *GImGui;
     g.HoveredId = id;
     g.HoveredIdAllowOverlap = false;
-    g.HoveredIdUsingMouseWheel = false;
     if (id != 0 && g.HoveredIdPreviousFrame != id)
         g.HoveredIdTimer = g.HoveredIdNotActiveTimer = 0.0f;
 }
@@ -4218,12 +4217,23 @@ static void ImGui::UpdateKeyboardInputs()
         }
 
     // Update keys
-    for (int i = 0; i < IM_ARRAYSIZE(io.KeysData); i++)
+    for (int i = 0; i < ImGuiKey_KeysData_SIZE; i++)
     {
         ImGuiKeyData* key_data = &io.KeysData[i];
         key_data->DownDurationPrev = key_data->DownDuration;
         key_data->DownDuration = key_data->Down ? (key_data->DownDuration < 0.0f ? 0.0f : key_data->DownDuration + io.DeltaTime) : -1.0f;
     }
+
+    // Update keys/input owner (named keys only): one entry per key
+    for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
+    {
+        ImGuiKeyData* key_data = &io.KeysData[key - ImGuiKey_KeysData_OFFSET];
+        ImGuiKeyOwnerData* owner_data = &g.KeysOwnerData[key - ImGuiKey_NamedKey_BEGIN];
+        owner_data->OwnerCurr = owner_data->OwnerNext;
+        if (!key_data->Down) // Important: ownership is released on the frame after a release. Ensure a 'MouseDown -> CloseWindow -> MouseUp' chain doesn't lead to someone else seeing the MouseUp.
+            owner_data->OwnerNext = ImGuiKeyOwner_None;
+        owner_data->LockThisFrame = owner_data->LockUntilRelease = owner_data->LockUntilRelease && key_data->Down;  // Clear LockUntilRelease when key is not Down anymore
+    }
 }
 
 static void ImGui::UpdateMouseInputs()
@@ -4312,13 +4322,9 @@ void ImGui::UpdateMouseWheel()
             LockWheelingWindow(NULL);
     }
 
-    const bool hovered_id_using_mouse_wheel = (g.HoveredIdPreviousFrame != 0 && g.HoveredIdPreviousFrameUsingMouseWheel);
-    const bool active_id_using_mouse_wheel_x = g.ActiveIdUsingKeyInputMask.TestBit(ImGuiKey_MouseWheelX);
-    const bool active_id_using_mouse_wheel_y = g.ActiveIdUsingKeyInputMask.TestBit(ImGuiKey_MouseWheelY);
-
     ImVec2 wheel;
-    wheel.x = (!hovered_id_using_mouse_wheel && !active_id_using_mouse_wheel_x) ? g.IO.MouseWheelH : 0.0f;
+    wheel.x = TestKeyOwner(ImGuiKey_MouseWheelX, ImGuiKeyOwner_None) ? g.IO.MouseWheelH : 0.0f;
-    wheel.y = (!hovered_id_using_mouse_wheel && !active_id_using_mouse_wheel_y) ? g.IO.MouseWheel : 0;
+    wheel.y = TestKeyOwner(ImGuiKey_MouseWheelY, ImGuiKeyOwner_None) ? g.IO.MouseWheel : 0.0f;
     if (wheel.x == 0.0f && wheel.y == 0.0f)
         return;
 
@@ -4546,10 +4552,8 @@ void ImGui::NewFrame()
     if (g.HoveredId && g.ActiveId != g.HoveredId)
         g.HoveredIdNotActiveTimer += g.IO.DeltaTime;
     g.HoveredIdPreviousFrame = g.HoveredId;
-    g.HoveredIdPreviousFrameUsingMouseWheel = g.HoveredIdUsingMouseWheel;
     g.HoveredId = 0;
     g.HoveredIdAllowOverlap = false;
-    g.HoveredIdUsingMouseWheel = false;
     g.HoveredIdDisabled = false;
 
     // Clear ActiveID if the item is not alive anymore.
@@ -4577,7 +4581,10 @@ void ImGui::NewFrame()
     if (g.ActiveId == 0)
     {
         g.ActiveIdUsingNavDirMask = 0x00;
-        g.ActiveIdUsingKeyInputMask.ClearAllBits();
+        g.ActiveIdUsingAllKeyboardKeys = false;
+#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
+        g.ActiveIdUsingNavInputMask = 0x00;
+#endif
     }
 
 #ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
@@ -4588,7 +4595,7 @@ void ImGui::NewFrame()
         // If your custom widget code used:                 { g.ActiveIdUsingNavInputMask |= (1 << ImGuiNavInput_Cancel); }
         // Since IMGUI_VERSION_NUM >= 18804 it should be:   { SetActiveIdUsingKey(ImGuiKey_Escape); SetActiveIdUsingKey(ImGuiKey_NavGamepadCancel); }
         if (g.ActiveIdUsingNavInputMask & (1 << ImGuiNavInput_Cancel))
-            SetActiveIdUsingKey(ImGuiKey_Escape);
+            SetKeyOwner(ImGuiKey_Escape, g.ActiveId);
         if (g.ActiveIdUsingNavInputMask & ~(1 << ImGuiNavInput_Cancel))
             IM_ASSERT(0); // Other values unsupported
     }
@@ -5388,29 +5395,13 @@ void ImGui::SetItemAllowOverlap()
         g.ActiveIdAllowOverlap = true;
 }
 
-void ImGui::SetItemUsingMouseWheel()
+// FIXME: It might be undesirable that this will likely disable KeyOwner-aware shortcuts systems. Consider a more fine-tuned version for the two users of this function.
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiID id = g.LastItemData.ID;
-    if (g.HoveredId == id)
-        g.HoveredIdUsingMouseWheel = true;
-    if (g.ActiveId == id)
-    {
-        g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_MouseWheelX);
-        g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_MouseWheelY);
-    }
-}
-
 void ImGui::SetActiveIdUsingAllKeyboardKeys()
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(g.ActiveId != 0);
     g.ActiveIdUsingNavDirMask = (1 << ImGuiDir_COUNT) - 1;
-    g.ActiveIdUsingKeyInputMask.SetBitRange(ImGuiKey_Keyboard_BEGIN, ImGuiKey_Keyboard_END);
+    g.ActiveIdUsingAllKeyboardKeys = true;
-    //g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_ModCtrl);
-    //g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_ModShift);
-    //g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_ModAlt);
-    //g.ActiveIdUsingKeyInputMask.SetBit(ImGuiKey_ModSuper);
     NavMoveRequestCancel();
 }
 
@@ -7950,7 +7941,7 @@ int ImGui::GetKeyPressedAmount(ImGuiKey key, float repeat_delay, float repeat_ra
 {
     ImGuiContext& g = *GImGui;
     const ImGuiKeyData* key_data = GetKeyData(key);
-    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on input ownership)
+    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
         return 0;
     const float t = key_data->DownDuration;
     return CalcTypematicRepeatAmount(t - g.IO.DeltaTime, t, repeat_delay, repeat_rate);
@@ -7967,24 +7958,30 @@ ImVec2 ImGui::GetKeyVector2d(ImGuiKey key_left, ImGuiKey key_right, ImGuiKey key
 // Note that Dear ImGui doesn't know the meaning/semantic of ImGuiKey from 0..511: they are legacy native keycodes.
 // Consider transitioning from 'IsKeyDown(MY_ENGINE_KEY_A)' (<1.87) to IsKeyDown(ImGuiKey_A) (>= 1.87)
 bool ImGui::IsKeyDown(ImGuiKey key)
+{
+    return IsKeyDown(key, ImGuiKeyOwner_Any);
+}
+
+bool ImGui::IsKeyDown(ImGuiKey key, ImGuiID owner_id)
 {
     const ImGuiKeyData* key_data = GetKeyData(key);
     if (!key_data->Down)
         return false;
+    if (!TestKeyOwner(key, owner_id))
+        return false;
     return true;
 }
 
 bool ImGui::IsKeyPressed(ImGuiKey key, bool repeat)
 {
-    return IsKeyPressedEx(key, repeat ? ImGuiInputFlags_Repeat : ImGuiInputFlags_None);
+    return IsKeyPressed(key, ImGuiKeyOwner_Any, repeat ? ImGuiInputFlags_Repeat : ImGuiInputFlags_None);
 }
 
-// Important: unlike legacy IsKeyPressed(ImGuiKey, bool repeat=true) which DEFAULT to repeat, this requires EXPLICIT repeat.
+// Important: unless legacy IsKeyPressed(ImGuiKey, bool repeat=true) which DEFAULT to repeat, this requires EXPLICIT repeat.
-// [Internal] 2022/07: Do not call this directly! It is a temporary entry point which we will soon replace with an overload for IsKeyPressed() when we introduce key ownership.
+bool ImGui::IsKeyPressed(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags)
-bool ImGui::IsKeyPressedEx(ImGuiKey key, ImGuiInputFlags flags)
 {
     const ImGuiKeyData* key_data = GetKeyData(key);
-    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on input ownership)
+    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
         return false;
     const float t = key_data->DownDuration;
     if (t < 0.0f)
@@ -7997,17 +7994,25 @@ bool ImGui::IsKeyPressedEx(ImGuiKey key, ImGuiInputFlags flags)
         GetTypematicRepeatRate(flags, &repeat_delay, &repeat_rate);
         pressed = (t > repeat_delay) && GetKeyPressedAmount(key, repeat_delay, repeat_rate) > 0;
     }
-
     if (!pressed)
         return false;
+    if (!TestKeyOwner(key, owner_id))
+        return false;
     return true;
 }
 
 bool ImGui::IsKeyReleased(ImGuiKey key)
+{
+    return IsKeyReleased(key, ImGuiKeyOwner_Any);
+}
+
+bool ImGui::IsKeyReleased(ImGuiKey key, ImGuiID owner_id)
 {
     const ImGuiKeyData* key_data = GetKeyData(key);
     if (key_data->DownDurationPrev < 0.0f || key_data->Down)
         return false;
+    if (!TestKeyOwner(key, owner_id))
+        return false;
     return true;
 }
 
@@ -8015,35 +8020,61 @@ bool ImGui::IsMouseDown(ImGuiMouseButton button)
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
-    return g.IO.MouseDown[button];
+    return g.IO.MouseDown[button] && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any); // should be same as IsKeyDown(MouseButtonToKey(button), ImGuiKeyOwner_Any), but this allows legacy code hijacking the io.Mousedown[] array.
+}
+
+bool ImGui::IsMouseDown(ImGuiMouseButton button, ImGuiID owner_id)
+{
+    ImGuiContext& g = *GImGui;
+    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
+    return g.IO.MouseDown[button] && TestKeyOwner(MouseButtonToKey(button), owner_id); // Should be same as IsKeyDown(MouseButtonToKey(button), owner_id), but this allows legacy code hijacking the io.Mousedown[] array.
 }
 
 bool ImGui::IsMouseClicked(ImGuiMouseButton button, bool repeat)
+{
+    return IsMouseClicked(button, ImGuiKeyOwner_Any, repeat ? ImGuiInputFlags_Repeat : ImGuiInputFlags_None);
+}
+
+bool ImGui::IsMouseClicked(ImGuiMouseButton button, ImGuiID owner_id, ImGuiInputFlags flags)
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
-    if (!g.IO.MouseDown[button]) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on input ownership)
+    if (!g.IO.MouseDown[button]) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
         return false;
     const float t = g.IO.MouseDownDuration[button];
-    if (t == 0.0f)
+    if (t < 0.0f)
-        return true;
+        return false;
-    if (repeat && t > g.IO.KeyRepeatDelay)
+
-        return CalcTypematicRepeatAmount(t - g.IO.DeltaTime, t, g.IO.KeyRepeatDelay, g.IO.KeyRepeatRate) > 0;
+    const bool repeat = (flags & ImGuiInputFlags_Repeat) != 0;
-    return false;
+    const bool pressed = (t == 0.0f) || (repeat && t > g.IO.KeyRepeatDelay && CalcTypematicRepeatAmount(t - g.IO.DeltaTime, t, g.IO.KeyRepeatDelay, g.IO.KeyRepeatRate) > 0);
+    if (!pressed)
+        return false;
+
+    if (!TestKeyOwner(MouseButtonToKey(button), owner_id))
+        return false;
+
+    return true;
 }
 
 bool ImGui::IsMouseReleased(ImGuiMouseButton button)
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
-    return g.IO.MouseReleased[button];
+    return g.IO.MouseReleased[button] && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any); // Should be same as IsKeyReleased(MouseButtonToKey(button), ImGuiKeyOwner_Any)
+}
+
+bool ImGui::IsMouseReleased(ImGuiMouseButton button, ImGuiID owner_id)
+{
+    ImGuiContext& g = *GImGui;
+    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
+    return g.IO.MouseReleased[button] && TestKeyOwner(MouseButtonToKey(button), owner_id); // Should be same as IsKeyReleased(MouseButtonToKey(button), owner_id)
 }
 
 bool ImGui::IsMouseDoubleClicked(ImGuiMouseButton button)
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
-    return g.IO.MouseClickedCount[button] == 2;
+    return g.IO.MouseClickedCount[button] == 2 && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any);
 }
 
 int ImGui::GetMouseClickedCount(ImGuiMouseButton button)
@@ -8305,6 +8336,98 @@ void ImGui::UpdateInputEvents(bool trickle_fast_inputs)
         g.IO.ClearInputKeys();
 }
 
+ImGuiID ImGui::GetKeyOwner(ImGuiKey key)
+{
+    if (!IsNamedKeyOrModKey(key))
+        return ImGuiKeyOwner_None;
+
+    ImGuiContext& g = *GImGui;
+    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(key);
+    ImGuiID owner_id = owner_data->OwnerCurr;
+
+    if (g.ActiveIdUsingAllKeyboardKeys && owner_id != g.ActiveId)
+        if ((key >= ImGuiKey_Keyboard_BEGIN && key < ImGuiKey_Keyboard_END) || key == ImGuiMod_Ctrl || key == ImGuiMod_Shift || key == ImGuiMod_Alt || key == ImGuiMod_Super)
+            return ImGuiKeyOwner_None;
+
+    return owner_id;
+}
+
+// TestKeyOwner(..., ID)   : (owner == None || owner == ID)
+// TestKeyOwner(..., None) : (owner == None)
+// TestKeyOwner(..., Any)  : no owner test
+// All paths are also testing for key not being locked, for the rare cases that key have been locked with using ImGuiInputFlags_LockXXX flags.
+bool ImGui::TestKeyOwner(ImGuiKey key, ImGuiID owner_id)
+{
+    if (!IsNamedKeyOrModKey(key))
+        return true;
+
+    ImGuiContext& g = *GImGui;
+    if (g.ActiveIdUsingAllKeyboardKeys && owner_id != g.ActiveId)
+        if ((key >= ImGuiKey_Keyboard_BEGIN && key < ImGuiKey_Keyboard_END) || key == ImGuiMod_Ctrl || key == ImGuiMod_Shift || key == ImGuiMod_Alt || key == ImGuiMod_Super)
+            return false;
+
+    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(key);
+    if (owner_id == ImGuiKeyOwner_Any)
+        return (owner_data->LockThisFrame == false);
+
+    // FIXME: For consistency with routing may be good to disable that, OR we could differentiate preemptive routing from setting owner on click.
+    // For now it is better to disable so we can actually get report of case where this may matter.
+    // -> Better to move in the SetKeyOwner() call, aka have a flag to set ->OwnerCurr in SetKeyOwner() ?
+    // May simply be inconsistent and unneeded to offer that feature:
+    //  - for typical keyboard/gamepad routing with multiple claims and ServeLast, we don't want to affect owner testing during the frame.
+    //  - for typical mouse routing overlap + hovered window generally prevents making it useful to alter owner testing during the frame.
+    //  - but effectively Locked flag can alter same-frame behavior.
+    //// We want OwnerNext to be handled immediately so SetKeyOwner(key, id1), TestKeyOwner(key, id2) == false
+    //if (owner_data->OwnerNext != ImGuiKeyOwner_None && owner_data->OwnerNext != owner)
+    //    return false;
+
+    if (owner_data->OwnerCurr != owner_id)
+    {
+        if (owner_data->LockThisFrame)
+            return false;
+        if (owner_data->OwnerCurr != ImGuiKeyOwner_None)
+            return false;
+    }
+
+    return true;
+}
+
+// When using _LockXXX flags, you can use ImGuiKeyOwner_Any to lock keys from everyone.
+// - SetKeyOwner(..., None)              : clears owner
+// - SetKeyOwner(..., Any, !Lock)        : illegal (assert)
+// - SetKeyOwner(..., Any or None, Lock) : set lock
+void ImGui::SetKeyOwner(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags)
+{
+    IM_ASSERT(IsNamedKeyOrModKey(key) && (owner_id != ImGuiKeyOwner_Any || (flags & (ImGuiInputFlags_LockThisFrame | ImGuiInputFlags_LockUntilRelease)))); // Can only use _Any with _LockXXX flags (to eat a key away without an ID to retrieve it)
+
+    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(key);
+    owner_data->OwnerNext = owner_id;
+
+    // We cannot lock by default as it would likely break lots of legacy code.
+    // In the case of using LockUntilRelease while key is not down we still lock during the frame (no key_data->Down test)
+    owner_data->LockUntilRelease = (flags & ImGuiInputFlags_LockUntilRelease) != 0;
+    owner_data->LockThisFrame = (flags & ImGuiInputFlags_LockThisFrame) != 0 || (owner_data->LockUntilRelease);
+    if (owner_data->LockThisFrame)
+        owner_data->OwnerCurr = owner_id;
+}
+
+// This is more or less equivalent to:
+//   if (IsItemHovered() || IsItemActive())
+//       SetKeyOwner(key, GetItemID());
+// Extensive uses of that (e.g. many calls for a single item) may want to manually perform the tests once and then call SetKeyOwner() multiple times.
+// More advanced usage scenarios may want to call SetKeyOwner() manually based on different condition.
+// Worth noting is that only one item can be hovered and only one item can be active, therefore this usage pattern doesn't need to bother with routing and priority.
+void ImGui::SetItemKeyOwner(ImGuiKey key, ImGuiInputFlags flags)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiID id = g.LastItemData.ID;
+    if (id == 0 || (g.HoveredId != id && g.ActiveId != id))
+        return;
+    if ((flags & ImGuiInputFlags_CondMask_) == 0)
+        flags |= ImGuiInputFlags_CondDefault_;
+    if ((g.HoveredId == id && (flags & ImGuiInputFlags_CondHovered)) || (g.ActiveId == id && (flags & ImGuiInputFlags_CondActive)))
+        SetKeyOwner(key, id, flags);
+}
 
 //-----------------------------------------------------------------------------
 // [SECTION] ERROR CHECKING
@@ -10692,10 +10815,10 @@ void ImGui::NavUpdateCreateMoveRequest()
         if (window && !g.NavWindowingTarget && !(window->Flags & ImGuiWindowFlags_NoNavInputs))
         {
             const ImGuiInputFlags repeat_mode = ImGuiInputFlags_Repeat | ImGuiInputFlags_RepeatRateNavMove;
-            if (!IsActiveIdUsingNavDir(ImGuiDir_Left)  && ((nav_gamepad_active && IsKeyPressedEx(ImGuiKey_GamepadDpadLeft,  repeat_mode)) || (nav_keyboard_active && IsKeyPressedEx(ImGuiKey_LeftArrow,  repeat_mode)))) { g.NavMoveDir = ImGuiDir_Left; }
+            if (!IsActiveIdUsingNavDir(ImGuiDir_Left)  && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadLeft,  ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_LeftArrow,  ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Left; }
-            if (!IsActiveIdUsingNavDir(ImGuiDir_Right) && ((nav_gamepad_active && IsKeyPressedEx(ImGuiKey_GamepadDpadRight, repeat_mode)) || (nav_keyboard_active && IsKeyPressedEx(ImGuiKey_RightArrow, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Right; }
+            if (!IsActiveIdUsingNavDir(ImGuiDir_Right) && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadRight, ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_RightArrow, ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Right; }
-            if (!IsActiveIdUsingNavDir(ImGuiDir_Up)    && ((nav_gamepad_active && IsKeyPressedEx(ImGuiKey_GamepadDpadUp,    repeat_mode)) || (nav_keyboard_active && IsKeyPressedEx(ImGuiKey_UpArrow,    repeat_mode)))) { g.NavMoveDir = ImGuiDir_Up; }
+            if (!IsActiveIdUsingNavDir(ImGuiDir_Up)    && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadUp,    ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_UpArrow,    ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Up; }
-            if (!IsActiveIdUsingNavDir(ImGuiDir_Down)  && ((nav_gamepad_active && IsKeyPressedEx(ImGuiKey_GamepadDpadDown,  repeat_mode)) || (nav_keyboard_active && IsKeyPressedEx(ImGuiKey_DownArrow,  repeat_mode)))) { g.NavMoveDir = ImGuiDir_Down; }
+            if (!IsActiveIdUsingNavDir(ImGuiDir_Down)  && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadDown,  ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_DownArrow,  ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Down; }
         }
         g.NavMoveClipDir = g.NavMoveDir;
         g.NavScoringNoClipRect = ImRect(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX);
@@ -10784,7 +10907,7 @@ void ImGui::NavUpdateCreateTabbingRequest()
     if (window == NULL || g.NavWindowingTarget != NULL || (window->Flags & ImGuiWindowFlags_NoNavInputs))
         return;
 
-    const bool tab_pressed = IsKeyPressed(ImGuiKey_Tab, true) && !IsActiveIdUsingKey(ImGuiKey_Tab) && !g.IO.KeyCtrl && !g.IO.KeyAlt;
+    const bool tab_pressed = IsKeyPressed(ImGuiKey_Tab, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat) && !g.IO.KeyCtrl && !g.IO.KeyAlt;
     if (!tab_pressed)
         return;
 
@@ -10902,14 +11025,13 @@ static void ImGui::NavUpdateCancelRequest()
     ImGuiContext& g = *GImGui;
     const bool nav_gamepad_active = (g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (g.IO.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
     const bool nav_keyboard_active = (g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
-    if (!(nav_keyboard_active && IsKeyPressed(ImGuiKey_Escape, false)) && !(nav_gamepad_active && IsKeyPressed(ImGuiKey_NavGamepadCancel, false)))
+    if (!(nav_keyboard_active && IsKeyPressed(ImGuiKey_Escape, ImGuiKeyOwner_None)) && !(nav_gamepad_active && IsKeyPressed(ImGuiKey_NavGamepadCancel, ImGuiKeyOwner_None)))
         return;
 
     IMGUI_DEBUG_LOG_NAV("[nav] NavUpdateCancelRequest()\n");
     if (g.ActiveId != 0)
     {
-        if (!IsActiveIdUsingKey(ImGuiKey_Escape) && !IsActiveIdUsingKey(ImGuiKey_NavGamepadCancel))
+        ClearActiveID();
-            ClearActiveID();
     }
     else if (g.NavLayer != ImGuiNavLayer_Main)
     {
@@ -10953,10 +11075,10 @@ static float ImGui::NavUpdatePageUpPageDown()
     if ((window->Flags & ImGuiWindowFlags_NoNavInputs) || g.NavWindowingTarget != NULL)
         return 0.0f;
 
-    const bool page_up_held = IsKeyDown(ImGuiKey_PageUp) && !IsActiveIdUsingKey(ImGuiKey_PageUp);
+    const bool page_up_held = IsKeyDown(ImGuiKey_PageUp, ImGuiKeyOwner_None);
-    const bool page_down_held = IsKeyDown(ImGuiKey_PageDown) && !IsActiveIdUsingKey(ImGuiKey_PageDown);
+    const bool page_down_held = IsKeyDown(ImGuiKey_PageDown, ImGuiKeyOwner_None);
-    const bool home_pressed = IsKeyPressed(ImGuiKey_Home) && !IsActiveIdUsingKey(ImGuiKey_Home);
+    const bool home_pressed = IsKeyPressed(ImGuiKey_Home, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat);
-    const bool end_pressed = IsKeyPressed(ImGuiKey_End) && !IsActiveIdUsingKey(ImGuiKey_End);
+    const bool end_pressed = IsKeyPressed(ImGuiKey_End, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat);
     if (page_up_held == page_down_held && home_pressed == end_pressed) // Proceed if either (not both) are pressed, otherwise early out
         return 0.0f;
 
@@ -10966,9 +11088,9 @@ static float ImGui::NavUpdatePageUpPageDown()
     if (window->DC.NavLayersActiveMask == 0x00 && window->DC.NavHasScroll)
     {
         // Fallback manual-scroll when window has no navigable item
-        if (IsKeyPressed(ImGuiKey_PageUp, true))
+        if (IsKeyPressed(ImGuiKey_PageUp, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat))
             SetScrollY(window, window->Scroll.y - window->InnerRect.GetHeight());
-        else if (IsKeyPressed(ImGuiKey_PageDown, true))
+        else if (IsKeyPressed(ImGuiKey_PageDown, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat))
             SetScrollY(window, window->Scroll.y + window->InnerRect.GetHeight());
         else if (home_pressed)
             SetScrollY(window, 0.0f);
@@ -11156,8 +11278,8 @@ static void ImGui::NavUpdateWindowing()
     // Start CTRL+Tab or Square+L/R window selection
     const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
     const bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
-    const bool start_windowing_with_gamepad = allow_windowing && nav_gamepad_active && !g.NavWindowingTarget && IsKeyPressed(ImGuiKey_NavGamepadMenu, false);
+    const bool start_windowing_with_gamepad = allow_windowing && nav_gamepad_active && !g.NavWindowingTarget && IsKeyPressed(ImGuiKey_NavGamepadMenu, 0, ImGuiInputFlags_None);
-    const bool start_windowing_with_keyboard = allow_windowing && !g.NavWindowingTarget && io.KeyCtrl && IsKeyPressed(ImGuiKey_Tab, false); // Note: enabled even without NavEnableKeyboard!
+    const bool start_windowing_with_keyboard = allow_windowing && !g.NavWindowingTarget && io.KeyCtrl && IsKeyPressed(ImGuiKey_Tab, ImGuiKeyOwner_None); // Note: enabled even without NavEnableKeyboard!
     if (start_windowing_with_gamepad || start_windowing_with_keyboard)
         if (ImGuiWindow* window = g.NavWindow ? g.NavWindow : FindWindowNavFocusable(g.WindowsFocusOrder.Size - 1, -INT_MAX, -1))
         {
@@ -11209,7 +11331,7 @@ static void ImGui::NavUpdateWindowing()
     // Keyboard: Press and Release ALT to toggle menu layer
     // - Testing that only Alt is tested prevents Alt+Shift or AltGR from toggling menu layer.
     // - AltGR is normally Alt+Ctrl but we can't reliably detect it (not all backends/systems/layout emit it as Alt+Ctrl). But even on keyboards without AltGR we don't want Alt+Ctrl to open menu anyway.
-    if (nav_keyboard_active && IsKeyPressed(ImGuiMod_Alt))
+    if (nav_keyboard_active && IsKeyPressed(ImGuiMod_Alt, ImGuiKeyOwner_None))
     {
         g.NavWindowingToggleLayer = true;
         g.NavInputSource = ImGuiInputSource_Keyboard;
@@ -11218,7 +11340,8 @@ static void ImGui::NavUpdateWindowing()
     {
         // We cancel toggling nav layer when any text has been typed (generally while holding Alt). (See #370)
         // We cancel toggling nav layer when other modifiers are pressed. (See #4439)
-        if (io.InputQueueCharacters.Size > 0 || io.KeyCtrl || io.KeyShift || io.KeySuper)
+        // We cancel toggling nav layer if an owner has claimed the key.
+        if (io.InputQueueCharacters.Size > 0 || io.KeyCtrl || io.KeyShift || io.KeySuper || TestKeyOwner(ImGuiMod_Alt, ImGuiKeyOwner_None) == false)
             g.NavWindowingToggleLayer = false;
 
         // Apply layer toggle on release
@@ -12946,7 +13069,26 @@ void ImGui::ShowMetricsWindow(bool* p_open)
         TreePop();
     }
 
-    // Misc Details
+    if (TreeNode("Key Owners"))
+    {
+        TextUnformatted("Key Owners:");
+        if (BeginListBox("##owners", ImVec2(-FLT_MIN, GetTextLineHeightWithSpacing() * 8)))
+        {
+            for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
+            {
+                ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(key);
+                if (owner_data->OwnerCurr == ImGuiKeyOwner_None)
+                    continue;
+                Text("%s: 0x%08X%s", GetKeyName(key), owner_data->OwnerCurr,
+                    owner_data->LockUntilRelease ? " LockUntilRelease" : owner_data->LockThisFrame ? " LockThisFrame" : "");
+                DebugLocateItemOnHover(owner_data->OwnerCurr);
+            }
+            EndListBox();
+        }
+        Text("(ActiveIdUsing: AllKeyboardKeys: %d, NavDirMask: 0x%X)", g.ActiveIdUsingAllKeyboardKeys, g.ActiveIdUsingNavDirMask);
+        TreePop();
+    }
+
     if (TreeNode("Internal state"))
     {
         Text("WINDOWING");
@@ -12962,11 +13104,7 @@ void ImGui::ShowMetricsWindow(bool* p_open)
         Text("ActiveId: 0x%08X/0x%08X (%.2f sec), AllowOverlap: %d, Source: %s", g.ActiveId, g.ActiveIdPreviousFrame, g.ActiveIdTimer, g.ActiveIdAllowOverlap, GetInputSourceName(g.ActiveIdSource));
         DebugLocateItemOnHover(g.ActiveId);
         Text("ActiveIdWindow: '%s'", g.ActiveIdWindow ? g.ActiveIdWindow->Name : "NULL");
-
+        Text("ActiveIdUsing: AllKeyboardKeys: %d, NavDirMask: %X", g.ActiveIdUsingAllKeyboardKeys, g.ActiveIdUsingNavDirMask);
-        int active_id_using_key_input_count = 0;
-        for (int n = ImGuiKey_NamedKey_BEGIN; n < ImGuiKey_NamedKey_END; n++)
-            active_id_using_key_input_count += g.ActiveIdUsingKeyInputMask[n] ? 1 : 0;
-        Text("ActiveIdUsing: NavDirMask: %X, KeyInputMask: %d key(s)", g.ActiveIdUsingNavDirMask, active_id_using_key_input_count);
         Text("HoveredId: 0x%08X (%.2f sec), AllowOverlap: %d", g.HoveredIdPreviousFrame, g.HoveredIdTimer, g.HoveredIdAllowOverlap); // Not displaying g.HoveredId as it is update mid-frame
         Text("HoverDelayId: 0x%08X, Timer: %.2f, ClearTimer: %.2f", g.HoverDelayId, g.HoverDelayTimer, g.HoverDelayClearTimer);
         Text("DragDrop: %d, SourceId = 0x%08X, Payload \"%s\" (%d bytes)", g.DragDropActive, g.DragDropPayload.SourceId, g.DragDropPayload.DataType, g.DragDropPayload.DataSize);

imgui.h

@@ -23,7 +23,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM > 12345')
 #define IMGUI_VERSION               "1.89 WIP"
-#define IMGUI_VERSION_NUM           18835
+#define IMGUI_VERSION_NUM           18836
 #define IMGUI_HAS_TABLE
 
 /*

imgui_internal.h

@@ -148,7 +148,7 @@ struct ImGuiWindowSettings;         // Storage for a window .ini settings (we ke
 typedef int ImGuiLayoutType;            // -> enum ImGuiLayoutType_         // Enum: Horizontal or vertical
 typedef int ImGuiActivateFlags;         // -> enum ImGuiActivateFlags_      // Flags: for navigation/focus function (will be for ActivateItem() later)
 typedef int ImGuiDebugLogFlags;         // -> enum ImGuiDebugLogFlags_      // Flags: for ShowDebugLogWindow(), g.DebugLogFlags
-typedef int ImGuiInputFlags;            // -> enum ImGuiInputFlags_         // Flags: for IsKeyPressedEx()
+typedef int ImGuiInputFlags;            // -> enum ImGuiInputFlags_         // Flags: for IsKeyPressed(), IsMouseClicked(), SetKeyOwner(), SetItemKeyOwner() etc.
 typedef int ImGuiItemFlags;             // -> enum ImGuiItemFlags_          // Flags: for PushItemFlag(), g.LastItemData.InFlags
 typedef int ImGuiItemStatusFlags;       // -> enum ImGuiItemStatusFlags_    // Flags: for g.LastItemData.StatusFlags
 typedef int ImGuiOldColumnFlags;        // -> enum ImGuiOldColumnFlags_     // Flags: for BeginColumns()
@@ -852,6 +852,8 @@ enum ImGuiButtonFlagsPrivate_
     ImGuiButtonFlags_NoHoldingActiveId      = 1 << 17,  // don't set ActiveId while holding the mouse (ImGuiButtonFlags_PressedOnClick only)
     ImGuiButtonFlags_NoNavFocus             = 1 << 18,  // don't override navigation focus when activated (FIXME: this is essentially used everytime an item uses ImGuiItemFlags_NoNav, but because legacy specs don't requires LastItemData to be set ButtonBehavior(), we can't poll g.LastItemData.InFlags)
     ImGuiButtonFlags_NoHoveredOnFocus       = 1 << 19,  // don't report as hovered when nav focus is on this item
+    ImGuiButtonFlags_NoSetKeyOwner          = 1 << 20,  // don't set key/input owner on the initial click (note: mouse buttons are keys! often, the key in question will be ImGuiKey_MouseLeft!)
+    ImGuiButtonFlags_NoTestKeyOwner         = 1 << 21,  // don't test key/input owner when polling the key (note: mouse buttons are keys! often, the key in question will be ImGuiKey_MouseLeft!)
     ImGuiButtonFlags_PressedOnMask_         = ImGuiButtonFlags_PressedOnClick | ImGuiButtonFlags_PressedOnClickRelease | ImGuiButtonFlags_PressedOnClickReleaseAnywhere | ImGuiButtonFlags_PressedOnRelease | ImGuiButtonFlags_PressedOnDoubleClick | ImGuiButtonFlags_PressedOnDragDropHold,
     ImGuiButtonFlags_PressedOnDefault_      = ImGuiButtonFlags_PressedOnClickRelease,
 };
@@ -881,6 +883,7 @@ enum ImGuiSelectableFlagsPrivate_
     ImGuiSelectableFlags_DrawHoveredWhenHeld    = 1 << 25,  // Always show active when held, even is not hovered. This concept could probably be renamed/formalized somehow.
     ImGuiSelectableFlags_SetNavIdOnHover        = 1 << 26,  // Set Nav/Focus ID on mouse hover (used by MenuItem)
     ImGuiSelectableFlags_NoPadWithHalfSpacing   = 1 << 27,  // Disable padding each side with ItemSpacing * 0.5f
+    ImGuiSelectableFlags_NoSetKeyOwner          = 1 << 28,  // Don't set key/input owner on the initial click (note: mouse buttons are keys! often, the key in question will be ImGuiKey_MouseLeft!)
 };
 
 // Extend ImGuiTreeNodeFlags_
@@ -1270,17 +1273,43 @@ struct ImGuiInputEvent
     ImGuiInputEvent() { memset(this, 0, sizeof(*this)); }
 };
 
-// Flags for IsKeyPressedEx(). In upcoming feature this will be used more (and IsKeyPressedEx() renamed)
+// Input function taking an 'ImGuiID owner_id' argument defaults to (ImGuiKeyOwner_Any == 0) aka don't test ownership, which matches legacy behavior.
+#define ImGuiKeyOwner_Any           ((ImGuiID)0)    // Accept key that have an owner, UNLESS a call to SetKeyOwner() explicitely used ImGuiInputFlags_LockThisFrame or ImGuiInputFlags_LockUntilRelease.
+#define ImGuiKeyOwner_None          ((ImGuiID)-1)   // Require key to have no owner.
+
+// This extend ImGuiKeyData but only for named keys (legacy keys don't support the new features)
+// Stored in main context (1 per named key). In the future might be merged into ImGuiKeyData.
+struct ImGuiKeyOwnerData
+{
+    ImGuiID     OwnerCurr;
+    ImGuiID     OwnerNext;
+    bool        LockThisFrame;      // Reading this key requires explicit owner id (until end of frame). Set by ImGuiInputFlags_LockThisFrame.
+    bool        LockUntilRelease;   // Reading this key requires explicit owner id (until key is released). Set by ImGuiInputFlags_LockUntilRelease. When this is true LockThisFrame is always true as well.
+
+    ImGuiKeyOwnerData()             { OwnerCurr = OwnerNext = ImGuiKeyOwner_None; LockThisFrame = LockUntilRelease = false; }
+};
+
+// Flags for extended versions of IsKeyPressed(), IsMouseClicked(), SetKeyOwner(), SetItemKeyOwner()
 // Don't mistake with ImGuiInputTextFlags! (for ImGui::InputText() function)
 enum ImGuiInputFlags_
 {
-    // Flags for IsKeyPressedEx()
+    // Flags for IsKeyPressed(), IsMouseClicked()
     ImGuiInputFlags_None                = 0,
     ImGuiInputFlags_Repeat              = 1 << 0,   // Return true on successive repeats. Default for legacy IsKeyPressed(). NOT Default for legacy IsMouseClicked(). MUST BE == 1.
     ImGuiInputFlags_RepeatRateDefault   = 1 << 1,   // Repeat rate: Regular (default)
     ImGuiInputFlags_RepeatRateNavMove   = 1 << 2,   // Repeat rate: Fast
     ImGuiInputFlags_RepeatRateNavTweak  = 1 << 3,   // Repeat rate: Faster
     ImGuiInputFlags_RepeatRateMask_     = ImGuiInputFlags_RepeatRateDefault | ImGuiInputFlags_RepeatRateNavMove | ImGuiInputFlags_RepeatRateNavTweak,
+
+    // Flags for SetItemKeyOwner()
+    ImGuiInputFlags_CondHovered         = 1 << 4,   // Only set if item is hovered (default to both)
+    ImGuiInputFlags_CondActive          = 1 << 5,   // Only set if item is active (default to both)
+    ImGuiInputFlags_CondDefault_        = ImGuiInputFlags_CondHovered | ImGuiInputFlags_CondActive,
+    ImGuiInputFlags_CondMask_           = ImGuiInputFlags_CondHovered | ImGuiInputFlags_CondActive,
+
+    // Flags for SetKeyOwner(), SetItemKeyOwner()
+    ImGuiInputFlags_LockThisFrame       = 1 << 6,   // Access to key data will requires EXPLICIT owner ID (ImGuiKeyOwner_Any/0 will NOT accepted for polling). Cleared at end of frame. This is useful to make input-owner-aware code steal keys from non-input-owner-aware code.
+    ImGuiInputFlags_LockUntilRelease    = 1 << 7,   // Access to key data will requires EXPLICIT owner ID (ImGuiKeyOwner_Any/0 will NOT accepted for polling). Cleared when key is released or at end of frame is not down. This is useful to make input-owner-aware code steal keys from non-input-owner-aware code.
 };
 
 //-----------------------------------------------------------------------------
@@ -1655,8 +1684,6 @@ struct ImGuiContext
     ImGuiID                 HoveredId;                          // Hovered widget, filled during the frame
     ImGuiID                 HoveredIdPreviousFrame;
     bool                    HoveredIdAllowOverlap;
-    bool                    HoveredIdUsingMouseWheel;           // Hovered widget will use mouse wheel. Blocks scrolling the underlying window.
-    bool                    HoveredIdPreviousFrameUsingMouseWheel;
     bool                    HoveredIdDisabled;                  // At least one widget passed the rect test, but has been discarded by disabled flag or popup inhibit. May be true even if HoveredId == 0.
     float                   HoveredIdTimer;                     // Measure contiguous hovering time
     float                   HoveredIdNotActiveTimer;            // Measure contiguous hovering time where the item has not been active
@@ -1680,9 +1707,12 @@ struct ImGuiContext
     ImGuiID                 LastActiveId;                       // Store the last non-zero ActiveId, useful for animation.
     float                   LastActiveIdTimer;                  // Store the last non-zero ActiveId timer since the beginning of activation, useful for animation.
 
-    // Input Ownership
+    // [EXPERIMENTAL] Key/Input Ownership
+    // - The idea is that instead of "eating" a given key, we can link to an owner.
+    // - Input query can then read input by specifying ImGuiKeyOwner_Any (== 0), ImGuiKeyOwner_None (== -1) or a custom ID.
+    ImGuiKeyOwnerData       KeysOwnerData[ImGuiKey_NamedKey_COUNT];
     ImU32                   ActiveIdUsingNavDirMask;            // Active widget will want to read those nav move requests (e.g. can activate a button and move away from it)
-    ImBitArrayForNamedKeys  ActiveIdUsingKeyInputMask;          // Active widget will want to read those key inputs. When we grow the ImGuiKey enum we'll need to either to order the enum to make useful keys come first, either redesign this into e.g. a small array.
+    bool                    ActiveIdUsingAllKeyboardKeys;       // Active widget will want to read all keyboard keys inputs. (FIXME: This is a shortcut for not taking ownership of 100+ keys but perhaps best to not have the inconsistency)
 #ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
     ImU32                   ActiveIdUsingNavInputMask;          // If you used this. Since (IMGUI_VERSION_NUM >= 18804) : 'g.ActiveIdUsingNavInputMask |= (1 << ImGuiNavInput_Cancel);' becomes 'SetActiveIdUsingKey(ImGuiKey_Escape); SetActiveIdUsingKey(ImGuiKey_NavGamepadCancel);'
 #endif
@@ -1911,7 +1941,6 @@ struct ImGuiContext
         DebugHookIdInfo = 0;
         HoveredId = HoveredIdPreviousFrame = 0;
         HoveredIdAllowOverlap = false;
-        HoveredIdUsingMouseWheel = HoveredIdPreviousFrameUsingMouseWheel = false;
         HoveredIdDisabled = false;
         HoveredIdTimer = HoveredIdNotActiveTimer = 0.0f;
         ActiveId = 0;
@@ -1935,7 +1964,7 @@ struct ImGuiContext
         LastActiveIdTimer = 0.0f;
 
         ActiveIdUsingNavDirMask = 0x00;
-        ActiveIdUsingKeyInputMask.ClearAllBits();
+        ActiveIdUsingAllKeyboardKeys = false;
 #ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
         ActiveIdUsingNavInputMask = 0x00;
 #endif
@@ -2749,21 +2778,44 @@ namespace ImGui
 
     IMGUI_API ImGuiKeyData* GetKeyData(ImGuiKey key);
     IMGUI_API void          GetKeyChordName(ImGuiKeyChord key_chord, char* out_buf, int out_buf_size);
-    IMGUI_API void          SetItemUsingMouseWheel();
-    IMGUI_API void          SetActiveIdUsingAllKeyboardKeys();
-    inline bool             IsActiveIdUsingNavDir(ImGuiDir dir)                         { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavDirMask & (1 << dir)) != 0; }
-    inline bool             IsActiveIdUsingKey(ImGuiKey key)                            { ImGuiContext& g = *GImGui; return g.ActiveIdUsingKeyInputMask[key]; }
-    inline void             SetActiveIdUsingKey(ImGuiKey key)                           { ImGuiContext& g = *GImGui; g.ActiveIdUsingKeyInputMask.SetBit(key); }
     inline ImGuiKey         MouseButtonToKey(ImGuiMouseButton button)                   { IM_ASSERT(button >= 0 && button < ImGuiMouseButton_COUNT); return (ImGuiKey)(ImGuiKey_MouseLeft + button); }
     IMGUI_API bool          IsMouseDragPastThreshold(ImGuiMouseButton button, float lock_threshold = -1.0f);
     IMGUI_API ImVec2        GetKeyVector2d(ImGuiKey key_left, ImGuiKey key_right, ImGuiKey key_up, ImGuiKey key_down);
     IMGUI_API float         GetNavTweakPressedAmount(ImGuiAxis axis);
     IMGUI_API int           CalcTypematicRepeatAmount(float t0, float t1, float repeat_delay, float repeat_rate);
     IMGUI_API void          GetTypematicRepeatRate(ImGuiInputFlags flags, float* repeat_delay, float* repeat_rate);
-    IMGUI_API bool          IsKeyPressedEx(ImGuiKey key, ImGuiInputFlags flags = 0);
+    IMGUI_API void          SetActiveIdUsingAllKeyboardKeys();
-#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
+    inline bool             IsActiveIdUsingNavDir(ImGuiDir dir)                         { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavDirMask & (1 << dir)) != 0; }
-    inline bool             IsKeyPressedMap(ImGuiKey key, bool repeat = true)           { IM_ASSERT(IsNamedKey(key)); return IsKeyPressed(key, repeat); } // [removed in 1.87]
+
-#endif
+    // [EXPERIMENTAL] Low-Level: Key/Input Ownership
+    // - The idea is that instead of "eating" a given input, we can link to an owner.
+    // - Ownership is most often claimed as a result of reacting to a press/down event (but occasionally may be claimed ahead).
+    // - Input queries can then read input by specifying ImGuiKeyOwner_Any (== 0), ImGuiKeyOwner_None (== -1) or a custom ID.
+    // - Legacy input queries (without specifying an owner or _Any or _None) are equivalent to using ImGuiKeyOwner_Any (== 0).
+    // - Input ownership is automatically released on the frame after a key is released. Therefore:
+    //   - for ownership registration happening a result of a down/press event, the SetKeyOwner() call may be done once (common case).
+    //   - for ownership registration happening ahead of a down/press event, the SetKeyOwner() call needs to be made every frame (happens if e.g. claiming ownership on hover).
+    // - SetItemKeyOwner() is a shortcut for common simple case. A custom widget will probably want to call SetKeyOwner() multiple times directly based on its interaction state.
+    // - This is marked experimental because not all widgets are fully honoring the Set/Test idioms. We will need to move forward step by step.
+    //   Please open a GitHub Issue to submit your usage scenario or if there's a use case you need solved.
+    IMGUI_API ImGuiID           GetKeyOwner(ImGuiKey key);
+    IMGUI_API void              SetKeyOwner(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags = 0);
+    IMGUI_API void              SetItemKeyOwner(ImGuiKey key, ImGuiInputFlags flags = 0);           // Set key owner to last item if it is hovered or active. Equivalent to 'if (IsItemHovered() || IsItemActive()) { SetKeyOwner(key, GetItemID());'.
+    IMGUI_API bool              TestKeyOwner(ImGuiKey key, ImGuiID owner_id);                       // Test that key is either not owned, either owned by 'owner_id'
+    inline ImGuiKeyOwnerData*   GetKeyOwnerData(ImGuiKey key)     { if (key & ImGuiMod_Mask_) key = ConvertSingleModFlagToKey(key); IM_ASSERT(IsNamedKey(key)); return &GImGui->KeysOwnerData[key - ImGuiKey_NamedKey_BEGIN]; }
+
+    // [EXPERIMENTAL] High-Level: Input Access functions w/ support for Key/Input Ownership
+    // - Important: legacy IsKeyPressed(ImGuiKey, bool repeat=true) _DEFAULTS_ to repeat, new IsKeyPressed() requires _EXPLICIT_ ImGuiInputFlags_Repeat flag.
+    // - Expected to be later promoted to public API, the prototypes are designed to replace existing ones (since owner_id can default to Any == 0)
+    // - Specifying a value for 'ImGuiID owner' will test that EITHER the key is NOT owned (UNLESS locked), EITHER the key is owned by 'owner'.
+    //   Legacy functions use ImGuiKeyOwner_Any meaning that they typically ignore ownership, unless a call to SetKeyOwner() explicitely used ImGuiInputFlags_LockThisFrame or ImGuiInputFlags_LockUntilRelease.
+    // - Binding generators may want to ignore those for now, or suffix them with Ex() until we decide if this gets moved into public API.
+    IMGUI_API bool              IsKeyDown(ImGuiKey key, ImGuiID owner_id);
+    IMGUI_API bool              IsKeyPressed(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags = 0);    // Important: when transitioning from old to new IsKeyPressed(): old API has "bool repeat = true", so would default to repeat. New API requiress explicit ImGuiInputFlags_Repeat.
+    IMGUI_API bool              IsKeyReleased(ImGuiKey key, ImGuiID owner_id);
+    IMGUI_API bool              IsMouseDown(ImGuiMouseButton button, ImGuiID owner_id);
+    IMGUI_API bool              IsMouseClicked(ImGuiMouseButton button, ImGuiID owner_id, ImGuiInputFlags flags = 0);
+    IMGUI_API bool              IsMouseReleased(ImGuiMouseButton button, ImGuiID owner_id);
 
     // [EXPERIMENTAL] Focus Scope
     // This is generally used to identify a unique input location (for e.g. a selection set)
@@ -2988,6 +3040,7 @@ namespace ImGui
 
     // Obsolete functions
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    inline void     SetItemUsingMouseWheel()                                            { SetItemKeyOwner(ImGuiKey_MouseWheelY); }      // Changed in 1.89
     inline bool     TreeNodeBehaviorIsOpen(ImGuiID id, ImGuiTreeNodeFlags flags = 0)    { return TreeNodeUpdateNextOpen(id, flags); }   // Renamed in 1.89
 
     // Refactored focus/nav/tabbing system in 1.82 and 1.84. If you have old/custom copy-and-pasted widgets that used FocusableItemRegister():
@@ -2998,6 +3051,9 @@ namespace ImGui
     inline bool     FocusableItemRegister(ImGuiWindow* window, ImGuiID id)              { IM_ASSERT(0); IM_UNUSED(window); IM_UNUSED(id); return false; } // -> pass ImGuiItemAddFlags_Inputable flag to ItemAdd()
     inline void     FocusableItemUnregister(ImGuiWindow* window)                        { IM_ASSERT(0); IM_UNUSED(window); }                              // -> unnecessary: TempInputText() uses ImGuiInputTextFlags_MergedItem
 #endif
+#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
+    inline bool     IsKeyPressedMap(ImGuiKey key, bool repeat = true)                   { IM_ASSERT(IsNamedKey(key)); return IsKeyPressed(key, repeat); } // Removed in 1.87: Mapping from named key is always identity!
+#endif
 
 } // namespace ImGui
 

imgui_widgets.cpp

@@ -541,18 +541,20 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
         hovered = false;
 
     // Mouse handling
+    const ImGuiID test_owner_id = (flags & ImGuiButtonFlags_NoTestKeyOwner) ? ImGuiKeyOwner_Any : id;
     if (hovered)
     {
         if (!(flags & ImGuiButtonFlags_NoKeyModifiers) || (!g.IO.KeyCtrl && !g.IO.KeyShift && !g.IO.KeyAlt))
         {
             // Poll buttons
             int mouse_button_clicked = -1;
-            if ((flags & ImGuiButtonFlags_MouseButtonLeft) && g.IO.MouseClicked[0])         { mouse_button_clicked = 0; }
+            if ((flags & ImGuiButtonFlags_MouseButtonLeft) && IsMouseClicked(0, test_owner_id))         { mouse_button_clicked = 0; }
-            else if ((flags & ImGuiButtonFlags_MouseButtonRight) && g.IO.MouseClicked[1])   { mouse_button_clicked = 1; }
+            else if ((flags & ImGuiButtonFlags_MouseButtonRight) && IsMouseClicked(1, test_owner_id))   { mouse_button_clicked = 1; }
-            else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && g.IO.MouseClicked[2])  { mouse_button_clicked = 2; }
+            else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && IsMouseClicked(2, test_owner_id))  { mouse_button_clicked = 2; }
-
             if (mouse_button_clicked != -1 && g.ActiveId != id)
             {
+                if (!(flags & ImGuiButtonFlags_NoSetKeyOwner))
+                    SetKeyOwner(MouseButtonToKey(mouse_button_clicked), id);
                 if (flags & (ImGuiButtonFlags_PressedOnClickRelease | ImGuiButtonFlags_PressedOnClickReleaseAnywhere))
                 {
                     SetActiveID(id, window);
@@ -577,9 +579,9 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
             if (flags & ImGuiButtonFlags_PressedOnRelease)
             {
                 int mouse_button_released = -1;
-                if ((flags & ImGuiButtonFlags_MouseButtonLeft) && g.IO.MouseReleased[0])        { mouse_button_released = 0; }
+                if ((flags & ImGuiButtonFlags_MouseButtonLeft) && IsMouseReleased(0, test_owner_id))        { mouse_button_released = 0; }
-                else if ((flags & ImGuiButtonFlags_MouseButtonRight) && g.IO.MouseReleased[1])  { mouse_button_released = 1; }
+                else if ((flags & ImGuiButtonFlags_MouseButtonRight) && IsMouseReleased(1, test_owner_id))  { mouse_button_released = 1; }
-                else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && g.IO.MouseReleased[2]) { mouse_button_released = 2; }
+                else if ((flags & ImGuiButtonFlags_MouseButtonMiddle) && IsMouseReleased(2, test_owner_id)) { mouse_button_released = 2; }
                 if (mouse_button_released != -1)
                 {
                     const bool has_repeated_at_least_once = (flags & ImGuiButtonFlags_Repeat) && g.IO.MouseDownDurationPrev[mouse_button_released] >= g.IO.KeyRepeatDelay; // Repeat mode trumps on release behavior
@@ -594,7 +596,7 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
             // 'Repeat' mode acts when held regardless of _PressedOn flags (see table above).
             // Relies on repeat logic of IsMouseClicked() but we may as well do it ourselves if we end up exposing finer RepeatDelay/RepeatRate settings.
             if (g.ActiveId == id && (flags & ImGuiButtonFlags_Repeat))
-                if (g.IO.MouseDownDuration[g.ActiveIdMouseButton] > 0.0f && IsMouseClicked(g.ActiveIdMouseButton, true))
+                if (g.IO.MouseDownDuration[g.ActiveIdMouseButton] > 0.0f && IsMouseClicked(g.ActiveIdMouseButton, test_owner_id, ImGuiInputFlags_Repeat))
                     pressed = true;
         }
 
@@ -640,8 +642,7 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
                 g.ActiveIdClickOffset = g.IO.MousePos - bb.Min;
 
             const int mouse_button = g.ActiveIdMouseButton;
-            IM_ASSERT(mouse_button >= 0 && mouse_button < ImGuiMouseButton_COUNT);
+            if (IsMouseDown(mouse_button, test_owner_id))
-            if (g.IO.MouseDown[mouse_button])
             {
                 held = true;
             }
@@ -654,7 +655,8 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
                     // Report as pressed when releasing the mouse (this is the most common path)
                     bool is_double_click_release = (flags & ImGuiButtonFlags_PressedOnDoubleClick) && g.IO.MouseReleased[mouse_button] && g.IO.MouseClickedLastCount[mouse_button] == 2;
                     bool is_repeating_already = (flags & ImGuiButtonFlags_Repeat) && g.IO.MouseDownDurationPrev[mouse_button] >= g.IO.KeyRepeatDelay; // Repeat mode trumps <on release>
-                    if (!is_double_click_release && !is_repeating_already)
+                    bool is_button_avail_or_owned = TestKeyOwner(MouseButtonToKey(mouse_button), test_owner_id);
+                    if (!is_double_click_release && !is_repeating_already && is_button_avail_or_owned)
                         pressed = true;
                 }
                 ClearActiveID();
@@ -2339,9 +2341,11 @@ bool ImGui::DragScalar(const char* label, ImGuiDataType data_type, void* p_data,
     {
         // Tabbing or CTRL-clicking on Drag turns it into an InputText
         const bool input_requested_by_tabbing = temp_input_allowed && (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_FocusedByTabbing) != 0;
-        const bool clicked = (hovered && g.IO.MouseClicked[0]);
+        const bool clicked = hovered && IsMouseClicked(0, id);
-        const bool double_clicked = (hovered && g.IO.MouseClickedCount[0] == 2);
+        const bool double_clicked = (hovered && g.IO.MouseClickedCount[0] == 2 && TestKeyOwner(ImGuiKey_MouseLeft, id));
         const bool make_active = (input_requested_by_tabbing || clicked || double_clicked || g.NavActivateId == id || g.NavActivateInputId == id);
+        if (make_active && (clicked || double_clicked))
+            SetKeyOwner(ImGuiKey_MouseLeft, id);
         if (make_active && temp_input_allowed)
             if (input_requested_by_tabbing || (clicked && g.IO.KeyCtrl) || double_clicked || g.NavActivateInputId == id)
                 temp_input_is_active = true;
@@ -2930,8 +2934,10 @@ bool ImGui::SliderScalar(const char* label, ImGuiDataType data_type, void* p_dat
     {
         // Tabbing or CTRL-clicking on Slider turns it into an input box
         const bool input_requested_by_tabbing = temp_input_allowed && (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_FocusedByTabbing) != 0;
-        const bool clicked = (hovered && g.IO.MouseClicked[0]);
+        const bool clicked = hovered && IsMouseClicked(0, id);
         const bool make_active = (input_requested_by_tabbing || clicked || g.NavActivateId == id || g.NavActivateInputId == id);
+        if (make_active && clicked)
+            SetKeyOwner(ImGuiKey_MouseLeft, id);
         if (make_active && temp_input_allowed)
             if (input_requested_by_tabbing || (clicked && g.IO.KeyCtrl) || g.NavActivateInputId == id)
                 temp_input_is_active = true;
@@ -3090,8 +3096,11 @@ bool ImGui::VSliderScalar(const char* label, const ImVec2& size, ImGuiDataType d
         format = DataTypeGetInfo(data_type)->PrintFmt;
 
     const bool hovered = ItemHoverable(frame_bb, id);
-    if ((hovered && g.IO.MouseClicked[0]) || g.NavActivateId == id || g.NavActivateInputId == id)
+    const bool clicked = hovered && IsMouseClicked(0, id);
+    if (clicked || g.NavActivateId == id || g.NavActivateInputId == id)
     {
+        if (clicked)
+            SetKeyOwner(ImGuiKey_MouseLeft, id);
         SetActiveID(id, window);
         SetFocusID(id, window);
         FocusWindow(window);
@@ -4087,23 +4096,27 @@ bool ImGui::InputTextEx(const char* label, const char* hint, char* buf, int buf_
         SetActiveID(id, window);
         SetFocusID(id, window);
         FocusWindow(window);
-
+    }
+    if (g.ActiveId == id)
+    {
         // Declare our inputs
+        if (user_clicked)
+            SetKeyOwner(ImGuiKey_MouseLeft, id);
         g.ActiveIdUsingNavDirMask |= (1 << ImGuiDir_Left) | (1 << ImGuiDir_Right);
         if (is_multiline || (flags & ImGuiInputTextFlags_CallbackHistory))
             g.ActiveIdUsingNavDirMask |= (1 << ImGuiDir_Up) | (1 << ImGuiDir_Down);
-        SetActiveIdUsingKey(ImGuiKey_Escape);
+        SetKeyOwner(ImGuiKey_Escape, id);
-        SetActiveIdUsingKey(ImGuiKey_NavGamepadCancel);
+        SetKeyOwner(ImGuiKey_NavGamepadCancel, id);
-        SetActiveIdUsingKey(ImGuiKey_Home);
+        SetKeyOwner(ImGuiKey_Home, id);
-        SetActiveIdUsingKey(ImGuiKey_End);
+        SetKeyOwner(ImGuiKey_End, id);
         if (is_multiline)
         {
-            SetActiveIdUsingKey(ImGuiKey_PageUp);
+            SetKeyOwner(ImGuiKey_PageUp, id);
-            SetActiveIdUsingKey(ImGuiKey_PageDown);
+            SetKeyOwner(ImGuiKey_PageDown, id);
         }
         if (flags & (ImGuiInputTextFlags_CallbackCompletion | ImGuiInputTextFlags_AllowTabInput)) // Disable keyboard tabbing out as we will use the \t character.
         {
-            SetActiveIdUsingKey(ImGuiKey_Tab);
+            SetKeyOwner(ImGuiKey_Tab, id);
         }
     }
 
@@ -6314,6 +6327,7 @@ bool ImGui::Selectable(const char* label, bool selected, ImGuiSelectableFlags fl
     // We use NoHoldingActiveID on menus so user can click and _hold_ on a menu then drag to browse child entries
     ImGuiButtonFlags button_flags = 0;
     if (flags & ImGuiSelectableFlags_NoHoldingActiveID) { button_flags |= ImGuiButtonFlags_NoHoldingActiveId; }
+    if (flags & ImGuiSelectableFlags_NoSetKeyOwner)   { button_flags |= ImGuiButtonFlags_NoSetKeyOwner; }
     if (flags & ImGuiSelectableFlags_SelectOnClick)     { button_flags |= ImGuiButtonFlags_PressedOnClick; }
     if (flags & ImGuiSelectableFlags_SelectOnRelease)   { button_flags |= ImGuiButtonFlags_PressedOnRelease; }
     if (flags & ImGuiSelectableFlags_AllowDoubleClick)  { button_flags |= ImGuiButtonFlags_PressedOnClickRelease | ImGuiButtonFlags_PressedOnDoubleClick; }
@@ -6996,7 +7010,9 @@ bool ImGui::BeginMenuEx(const char* label, const char* icon, bool enabled)
         BeginDisabled();
     const ImGuiMenuColumns* offsets = &window->DC.MenuColumns;
     bool pressed;
-    const ImGuiSelectableFlags selectable_flags = ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups;
+
+    // We use ImGuiSelectableFlags_NoSetKeyOwner to allow down on one menu item, move, up on another.
+    const ImGuiSelectableFlags selectable_flags = ImGuiSelectableFlags_NoHoldingActiveID | ImGuiSelectableFlags_NoSetKeyOwner | ImGuiSelectableFlags_SelectOnClick | ImGuiSelectableFlags_DontClosePopups;
     if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
     {
         // Menu inside an horizontal menu bar
@@ -7188,7 +7204,8 @@ bool ImGui::MenuItemEx(const char* label, const char* icon, const char* shortcut
     if (!enabled)
         BeginDisabled();
 
-    const ImGuiSelectableFlags selectable_flags = ImGuiSelectableFlags_SelectOnRelease | ImGuiSelectableFlags_SetNavIdOnHover;
+    // We use ImGuiSelectableFlags_NoSetKeyOwner to allow down on one menu item, move, up on another.
+    const ImGuiSelectableFlags selectable_flags = ImGuiSelectableFlags_SelectOnRelease | ImGuiSelectableFlags_NoSetKeyOwner | ImGuiSelectableFlags_SetNavIdOnHover;
     const ImGuiMenuColumns* offsets = &window->DC.MenuColumns;
     if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
     {