Merge misc changes from docking branch to reduce small drift.

In particular:
- imgui.cpp : move UpdateInputEvents() higher in NewFrame() to match docking + update RenderMouseCursor() to match.
- imgui_draw.cpp: ImDrawList::_ResetForNewFrame() change from c807192ab
- Backends: SDL2. Add MouseWindowID + change SDL_CaptureMouse() test to match docking branch. Not strictly necessary but aimed at reducing drift because we go on and fork this file.
+ moved responsability of checking valid names to TabBarGetTabName() to simplify both branches.

backends/imgui_impl_allegro5.cpp

@@ -275,7 +275,7 @@ void ImGui_ImplAllegro5_InvalidateDeviceObjects()
     ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
     if (bd->Texture)
     {
-        io.Fonts->SetTexID(nullptr);
+        io.Fonts->SetTexID(0);
         al_destroy_bitmap(bd->Texture);
         bd->Texture = nullptr;
     }

backends/imgui_impl_dx10.cpp

@@ -2,8 +2,8 @@
 // This needs to be used along with a Platform Backend (e.g. Win32)
 
 // Implemented features:
-//  [X] Renderer: User texture backend. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -515,7 +515,7 @@ void    ImGui_ImplDX10_InvalidateDeviceObjects()
         return;
 
     if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
-    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(nullptr); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
     if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }

backends/imgui_impl_dx10.h

@@ -2,8 +2,8 @@
 // This needs to be used along with a Platform Backend (e.g. Win32)
 
 // Implemented features:
-//  [X] Renderer: User texture backend. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. 
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_dx11.cpp

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -527,7 +527,7 @@ void    ImGui_ImplDX11_InvalidateDeviceObjects()
         return;
 
     if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
-    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(nullptr); } // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
     if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }

backends/imgui_impl_dx11.h

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. 
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_dx12.cpp

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
 // This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
@@ -50,6 +50,33 @@
 #endif
 
 // DirectX data
+struct ImGui_ImplDX12_RenderBuffers;
+struct ImGui_ImplDX12_Data
+{
+    ID3D12Device*               pd3dDevice;
+    ID3D12RootSignature*        pRootSignature;
+    ID3D12PipelineState*        pPipelineState;
+    DXGI_FORMAT                 RTVFormat;
+    ID3D12Resource*             pFontTextureResource;
+    D3D12_CPU_DESCRIPTOR_HANDLE hFontSrvCpuDescHandle;
+    D3D12_GPU_DESCRIPTOR_HANDLE hFontSrvGpuDescHandle;
+    ID3D12DescriptorHeap*       pd3dSrvDescHeap;
+    UINT                        numFramesInFlight;
+
+    ImGui_ImplDX12_RenderBuffers* pFrameResources;
+    UINT                        frameIndex;
+
+    ImGui_ImplDX12_Data()       { memset((void*)this, 0, sizeof(*this)); frameIndex = UINT_MAX; }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplDX12_Data* ImGui_ImplDX12_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplDX12_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Buffers used during the rendering of a frame
 struct ImGui_ImplDX12_RenderBuffers
 {
     ID3D12Resource*     IndexBuffer;
@@ -58,35 +85,11 @@ struct ImGui_ImplDX12_RenderBuffers
     int                 VertexBufferSize;
 };
 
-struct ImGui_ImplDX12_Data
-{
-    ID3D12Device*                   pd3dDevice;
-    ID3D12RootSignature*            pRootSignature;
-    ID3D12PipelineState*            pPipelineState;
-    DXGI_FORMAT                     RTVFormat;
-    ID3D12Resource*                 pFontTextureResource;
-    D3D12_CPU_DESCRIPTOR_HANDLE     hFontSrvCpuDescHandle;
-    D3D12_GPU_DESCRIPTOR_HANDLE     hFontSrvGpuDescHandle;
-
-    ImGui_ImplDX12_RenderBuffers*   pFrameResources;
-    UINT                            numFramesInFlight;
-    UINT                            frameIndex;
-
-    ImGui_ImplDX12_Data()           { memset((void*)this, 0, sizeof(*this)); frameIndex = UINT_MAX; }
-};
-
 struct VERTEX_CONSTANT_BUFFER_DX12
 {
     float   mvp[4][4];
 };
 
-// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
-// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
-static ImGui_ImplDX12_Data* ImGui_ImplDX12_GetBackendData()
-{
-    return ImGui::GetCurrentContext() ? (ImGui_ImplDX12_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
-}
-
 // Functions
 static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx, ImGui_ImplDX12_RenderBuffers* fr)
 {
@@ -676,8 +679,8 @@ void    ImGui_ImplDX12_InvalidateDeviceObjects()
     ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
     if (!bd || !bd->pd3dDevice)
         return;
-    ImGuiIO& io = ImGui::GetIO();
 
+    ImGuiIO& io = ImGui::GetIO();
     SafeRelease(bd->pRootSignature);
     SafeRelease(bd->pPipelineState);
     SafeRelease(bd->pFontTextureResource);
@@ -709,8 +712,8 @@ bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FO
     bd->hFontSrvGpuDescHandle = font_srv_gpu_desc_handle;
     bd->pFrameResources = new ImGui_ImplDX12_RenderBuffers[num_frames_in_flight];
     bd->numFramesInFlight = num_frames_in_flight;
+    bd->pd3dSrvDescHeap = cbv_srv_heap;
     bd->frameIndex = UINT_MAX;
-    IM_UNUSED(cbv_srv_heap); // Unused in master branch (will be used by multi-viewports)
 
     // Create buffers with a default size (they will later be grown as needed)
     for (int i = 0; i < num_frames_in_flight; i++)
@@ -731,6 +734,7 @@ void ImGui_ImplDX12_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    // Clean up windows and device objects
     ImGui_ImplDX12_InvalidateDeviceObjects();
     delete[] bd->pFrameResources;
     io.BackendRendererName = nullptr;

backends/imgui_impl_dx12.h

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
 // See imgui_impl_dx12.cpp file for details.

backends/imgui_impl_dx9.cpp

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -366,7 +366,7 @@ void ImGui_ImplDX9_InvalidateDeviceObjects()
         return;
     if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
-    if (bd->FontTexture) { bd->FontTexture->Release(); bd->FontTexture = nullptr; ImGui::GetIO().Fonts->SetTexID(nullptr); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    if (bd->FontTexture) { bd->FontTexture->Release(); bd->FontTexture = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
 }
 
 void ImGui_ImplDX9_NewFrame()

backends/imgui_impl_dx9.h

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. 
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_glfw.cpp

@@ -1,7 +1,7 @@
 // dear imgui: Platform Backend for GLFW
 // This needs to be used along with a Renderer (e.g. OpenGL3, Vulkan, WebGPU..)
 // (Info: GLFW is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
-// (Requires: GLFW 3.1+)
+// (Requires: GLFW 3.1+. Prefer GLFW 3.3+ or GLFW 3.4+ for full feature support.)
 
 // Implemented features:
 //  [X] Platform: Clipboard support.
@@ -70,10 +70,15 @@
 
 // GLFW
 #include <GLFW/glfw3.h>
+
 #ifdef _WIN32
 #undef APIENTRY
 #define GLFW_EXPOSE_NATIVE_WIN32
-#include <GLFW/glfw3native.h>   // for glfwGetWin32Window
+#include <GLFW/glfw3native.h>   // for glfwGetWin32Window()
+#endif
+#ifdef __APPLE__
+#define GLFW_EXPOSE_NATIVE_COCOA
+#include <GLFW/glfw3native.h>   // for glfwGetCocoaWindow()
 #endif
 
 #ifdef __EMSCRIPTEN__
@@ -509,11 +514,6 @@ static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, Glfw
     io.GetClipboardTextFn = ImGui_ImplGlfw_GetClipboardText;
     io.ClipboardUserData = bd->Window;
 
-    // Set platform dependent data in viewport
-#if defined(_WIN32)
-    ImGui::GetMainViewport()->PlatformHandleRaw = (void*)glfwGetWin32Window(bd->Window);
-#endif
-
     // Create mouse cursors
     // (By design, on X11 cursors are user configurable and some cursors may be missing. When a cursor doesn't exist,
     // GLFW will emit an error which will often be printed by the app, so we temporarily disable error reporting.
@@ -543,7 +543,6 @@ static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, Glfw
     // Chain GLFW callbacks: our callbacks will call the user's previously installed callbacks, if any.
     if (install_callbacks)
         ImGui_ImplGlfw_InstallCallbacks(window);
-
     // Register Emscripten Wheel callback to workaround issue in Emscripten GLFW Emulation (#6096)
     // We intentionally do not check 'if (install_callbacks)' here, as some users may set it to false and call GLFW callback themselves.
     // FIXME: May break chaining in case user registered their own Emscripten callback?
@@ -551,6 +550,14 @@ static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, Glfw
     emscripten_set_wheel_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, NULL, false, ImGui_ImplEmscripten_WheelCallback);
 #endif
 
+    // Set platform dependent data in viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+#ifdef _WIN32
+    main_viewport->PlatformHandleRaw = glfwGetWin32Window(bd->Window);
+#elif defined(__APPLE__)
+    main_viewport->PlatformHandleRaw = (void*)glfwGetCocoaWindow(bd->Window);
+#endif
+
     bd->ClientApi = client_api;
     return true;
 }
@@ -598,24 +605,29 @@ static void ImGui_ImplGlfw_UpdateMouseData()
         return;
     }
 
+    // (those braces are here to reduce diff with multi-viewports support in 'docking' branch)
+    {
+        GLFWwindow* window = bd->Window;
+
 #ifdef __EMSCRIPTEN__
-    const bool is_app_focused = true;
+        const bool is_window_focused = true;
 #else
-    const bool is_app_focused = glfwGetWindowAttrib(bd->Window, GLFW_FOCUSED) != 0;
+        const bool is_window_focused = glfwGetWindowAttrib(window, GLFW_FOCUSED) != 0;
 #endif
-    if (is_app_focused)
-    {
-        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
-        if (io.WantSetMousePos)
-            glfwSetCursorPos(bd->Window, (double)io.MousePos.x, (double)io.MousePos.y);
-
-        // (Optional) Fallback to provide mouse position when focused (ImGui_ImplGlfw_CursorPosCallback already provides this when hovered or captured)
-        if (is_app_focused && bd->MouseWindow == nullptr)
+        if (is_window_focused)
         {
-            double mouse_x, mouse_y;
-            glfwGetCursorPos(bd->Window, &mouse_x, &mouse_y);
-            io.AddMousePosEvent((float)mouse_x, (float)mouse_y);
-            bd->LastValidMousePos = ImVec2((float)mouse_x, (float)mouse_y);
+            // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+            if (io.WantSetMousePos)
+                glfwSetCursorPos(window, (double)io.MousePos.x, (double)io.MousePos.y);
+
+            // (Optional) Fallback to provide mouse position when focused (ImGui_ImplGlfw_CursorPosCallback already provides this when hovered or captured)
+            if (bd->MouseWindow == nullptr)
+            {
+                double mouse_x, mouse_y;
+                glfwGetCursorPos(window, &mouse_x, &mouse_y);
+                bd->LastValidMousePos = ImVec2((float)mouse_x, (float)mouse_y);
+                io.AddMousePosEvent((float)mouse_x, (float)mouse_y);
+            }
         }
     }
 }
@@ -628,17 +640,21 @@ static void ImGui_ImplGlfw_UpdateMouseCursor()
         return;
 
     ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
-    if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
-    {
-        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
-        glfwSetInputMode(bd->Window, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
-    }
-    else
+    // (those braces are here to reduce diff with multi-viewports support in 'docking' branch)
     {
-        // Show OS mouse cursor
-        // FIXME-PLATFORM: Unfocused windows seems to fail changing the mouse cursor with GLFW 3.2, but 3.3 works here.
-        glfwSetCursor(bd->Window, bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow]);
-        glfwSetInputMode(bd->Window, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
+        GLFWwindow* window = bd->Window;
+        if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
+        {
+            // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+            glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_HIDDEN);
+        }
+        else
+        {
+            // Show OS mouse cursor
+            // FIXME-PLATFORM: Unfocused windows seems to fail changing the mouse cursor with GLFW 3.2, but 3.3 works here.
+            glfwSetCursor(window, bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow]);
+            glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
+        }
     }
 }
 

backends/imgui_impl_metal.h

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. 
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_metal.mm

@@ -3,7 +3,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -70,16 +70,16 @@
 
 struct ImGui_ImplMetal_Data
 {
-    MetalContext*            SharedMetalContext;
+    MetalContext*               SharedMetalContext;
 
-    ImGui_ImplMetal_Data()  { memset(this, 0, sizeof(*this)); }
+    ImGui_ImplMetal_Data()      { memset(this, 0, sizeof(*this)); }
 };
 
-static ImGui_ImplMetal_Data*     ImGui_ImplMetal_CreateBackendData()  { return IM_NEW(ImGui_ImplMetal_Data)(); }
-static ImGui_ImplMetal_Data*     ImGui_ImplMetal_GetBackendData()     { return ImGui::GetCurrentContext() ? (ImGui_ImplMetal_Data*)ImGui::GetIO().BackendRendererUserData : NULL; }
-static void                      ImGui_ImplMetal_DestroyBackendData() { IM_DELETE(ImGui_ImplMetal_GetBackendData()); }
+static ImGui_ImplMetal_Data*    ImGui_ImplMetal_CreateBackendData() { return IM_NEW(ImGui_ImplMetal_Data)(); }
+static ImGui_ImplMetal_Data*    ImGui_ImplMetal_GetBackendData()    { return ImGui::GetCurrentContext() ? (ImGui_ImplMetal_Data*)ImGui::GetIO().BackendRendererUserData : nullptr; }
+static void                     ImGui_ImplMetal_DestroyBackendData(){ IM_DELETE(ImGui_ImplMetal_GetBackendData()); }
 
-static inline CFTimeInterval     GetMachAbsoluteTimeInSeconds()       { return static_cast<CFTimeInterval>(static_cast<double>(clock_gettime_nsec_np(CLOCK_UPTIME_RAW)) / 1e9); }
+static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
 
 #ifdef IMGUI_IMPL_METAL_CPP
 
@@ -297,7 +297,7 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> c
     {
         dispatch_async(dispatch_get_main_queue(), ^{
             ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
-            if (bd != NULL)
+            if (bd != nullptr)
             {
                 @synchronized(bd->SharedMetalContext.bufferCache)
                 {

backends/imgui_impl_opengl3.cpp

@@ -5,7 +5,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
-//  [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_opengl3.h

@@ -5,7 +5,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
-//  [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_osx.h

@@ -9,7 +9,7 @@
 //  [X] Platform: OSX clipboard is supported within core Dear ImGui (no specific code in this backend).
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
 //  [X] Platform: IME support.
-//
+
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
 // If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.

backends/imgui_impl_osx.mm

@@ -66,22 +66,22 @@
 // Data
 struct ImGui_ImplOSX_Data
 {
-    CFTimeInterval          Time;
-    NSCursor*               MouseCursors[ImGuiMouseCursor_COUNT];
-    bool                    MouseCursorHidden;
-    ImGuiObserver*          Observer;
-    KeyEventResponder*      KeyEventResponder;
-    NSTextInputContext*     InputContext;
-    id                      Monitor;
-
-    ImGui_ImplOSX_Data()    { memset(this, 0, sizeof(*this)); }
+    CFTimeInterval              Time;
+    NSCursor*                   MouseCursors[ImGuiMouseCursor_COUNT];
+    bool                        MouseCursorHidden;
+    ImGuiObserver*              Observer;
+    KeyEventResponder*          KeyEventResponder;
+    NSTextInputContext*         InputContext;
+    id                          Monitor;
+
+    ImGui_ImplOSX_Data()        { memset(this, 0, sizeof(*this)); }
 };
 
-static ImGui_ImplOSX_Data*  ImGui_ImplOSX_CreateBackendData()  { return IM_NEW(ImGui_ImplOSX_Data)(); }
-static ImGui_ImplOSX_Data*  ImGui_ImplOSX_GetBackendData()     { return (ImGui_ImplOSX_Data*)ImGui::GetIO().BackendPlatformUserData; }
-static void                 ImGui_ImplOSX_DestroyBackendData() { IM_DELETE(ImGui_ImplOSX_GetBackendData()); }
+static ImGui_ImplOSX_Data*      ImGui_ImplOSX_CreateBackendData()   { return IM_NEW(ImGui_ImplOSX_Data)(); }
+static ImGui_ImplOSX_Data*      ImGui_ImplOSX_GetBackendData()      { return (ImGui_ImplOSX_Data*)ImGui::GetIO().BackendPlatformUserData; }
+static void                     ImGui_ImplOSX_DestroyBackendData()  { IM_DELETE(ImGui_ImplOSX_GetBackendData()); }
 
-static inline CFTimeInterval GetMachAbsoluteTimeInSeconds()    { return static_cast<CFTimeInterval>(static_cast<double>(clock_gettime_nsec_np(CLOCK_UPTIME_RAW)) / 1e9); }
+static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
 
 // Forward Declarations
 static void ImGui_ImplOSX_AddTrackingArea(NSView* _Nonnull view);
@@ -391,8 +391,6 @@ bool ImGui_ImplOSX_Init(NSView* view)
     // Setup backend capabilities flags
     io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
     //io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
-    //io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports;    // We can create multi-viewports on the Platform side (optional)
-    //io.BackendFlags |= ImGuiBackendFlags_HasMouseHoveredViewport; // We can set io.MouseHoveredViewport correctly (optional, not easy)
     io.BackendPlatformName = "imgui_impl_osx";
 
     bd->Observer = [ImGuiObserver new];
@@ -476,11 +474,11 @@ bool ImGui_ImplOSX_Init(NSView* view)
 void ImGui_ImplOSX_Shutdown()
 {
     ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
-    bd->Observer = NULL;
-    if (bd->Monitor != NULL)
+    bd->Observer = nullptr;
+    if (bd->Monitor != nullptr)
     {
         [NSEvent removeMonitor:bd->Monitor];
-        bd->Monitor = NULL;
+        bd->Monitor = nullptr;
     }
     ImGui_ImplOSX_DestroyBackendData();
 }

backends/imgui_impl_sdl2.cpp

@@ -91,6 +91,7 @@ struct ImGui_ImplSDL2_Data
     SDL_Window*     Window;
     SDL_Renderer*   Renderer;
     Uint64          Time;
+    Uint32          MouseWindowID;
     int             MouseButtonsDown;
     SDL_Cursor*     MouseCursors[ImGuiMouseCursor_COUNT];
     SDL_Cursor*     LastMouseCursor;
@@ -261,7 +262,8 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
     {
         case SDL_MOUSEMOTION:
         {
-            io.AddMousePosEvent((float)event->motion.x, (float)event->motion.y);
+            ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
             return true;
         }
         case SDL_MOUSEWHEEL:
@@ -318,7 +320,10 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
             //   we delay process the SDL_WINDOWEVENT_LEAVE events by one frame. See issue #5012 for details.
             Uint8 window_event = event->window.event;
             if (window_event == SDL_WINDOWEVENT_ENTER)
+            {
+                bd->MouseWindowID = event->window.windowID;
                 bd->PendingMouseLeaveFrame = 0;
+            }
             if (window_event == SDL_WINDOWEVENT_LEAVE)
                 bd->PendingMouseLeaveFrame = ImGui::GetFrameCount() + 1;
             if (window_event == SDL_WINDOWEVENT_FOCUS_GAINED)
@@ -374,14 +379,19 @@ static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
     bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_NO);
 
     // Set platform dependent data in viewport
-#if defined(SDL_VIDEO_DRIVER_WINDOWS)
+    // Our mouse update function expect PlatformHandle to be filled for the main viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandleRaw = nullptr;
     SDL_SysWMinfo info;
     SDL_VERSION(&info.version);
     if (SDL_GetWindowWMInfo(window, &info))
-        ImGui::GetMainViewport()->PlatformHandleRaw = (void*)info.info.win.window;
-#else
-    (void)window;
+    {
+#if defined(SDL_VIDEO_DRIVER_WINDOWS)
+        main_viewport->PlatformHandleRaw = (void*)info.info.win.window;
+#elif defined(__APPLE__) && defined(SDL_VIDEO_DRIVER_COCOA)
+        main_viewport->PlatformHandleRaw = (void*)info.info.cocoa.window;
 #endif
+    }
 
     // From 2.0.5: Set SDL hint to receive mouse click events on window focus, otherwise SDL doesn't emit the event.
     // Without this, when clicking to gain focus, our widgets wouldn't activate even though they showed as hovered.
@@ -457,7 +467,7 @@ static void ImGui_ImplSDL2_UpdateMouseData()
     // We forward mouse input when hovered or captured (via SDL_MOUSEMOTION) or when focused (below)
 #if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
     // SDL_CaptureMouse() let the OS know e.g. that our imgui drag outside the SDL window boundaries shouldn't e.g. trigger other operations outside
-    SDL_CaptureMouse((bd->MouseButtonsDown != 0 && ImGui::GetDragDropPayload() == nullptr) ? SDL_TRUE : SDL_FALSE);
+    SDL_CaptureMouse((bd->MouseButtonsDown != 0) ? SDL_TRUE : SDL_FALSE);
     SDL_Window* focused_window = SDL_GetKeyboardFocus();
     const bool is_app_focused = (bd->Window == focused_window);
 #else
@@ -580,8 +590,9 @@ void ImGui_ImplSDL2_NewFrame()
 
     if (bd->PendingMouseLeaveFrame && bd->PendingMouseLeaveFrame >= ImGui::GetFrameCount() && bd->MouseButtonsDown == 0)
     {
-        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+        bd->MouseWindowID = 0;
         bd->PendingMouseLeaveFrame = 0;
+        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
     }
 
     ImGui_ImplSDL2_UpdateMouseData();

backends/imgui_impl_sdlrenderer.cpp

@@ -10,8 +10,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
-// Missing features:
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.

backends/imgui_impl_sdlrenderer.h

@@ -10,7 +10,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 #pragma once
 #include "imgui.h"      // IMGUI_IMPL_API

backends/imgui_impl_vulkan.cpp

@@ -2,8 +2,8 @@
 // This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
 
 // Implemented features:
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
 //  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
 // This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
@@ -117,7 +117,7 @@ struct ImGui_ImplVulkan_Data
     VkDeviceMemory              UploadBufferMemory;
     VkBuffer                    UploadBuffer;
 
-    // Render buffers
+    // Render buffers for main window
     ImGui_ImplVulkanH_WindowRenderBuffers MainWindowRenderBuffers;
 
     ImGui_ImplVulkan_Data()

backends/imgui_impl_vulkan.h

@@ -2,8 +2,8 @@
 // This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
 
 // Implemented features:
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
 //  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
 // See imgui_impl_vulkan.cpp file for details.
@@ -89,8 +89,8 @@ IMGUI_IMPL_API bool         ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*l
 // You probably do NOT need to use or care about those functions.
 // Those functions only exist because:
 //   1) they facilitate the readability and maintenance of the multiple main.cpp examples files.
-//   2) the upcoming multi-viewport feature will need them internally.
-// Generally we avoid exposing any kind of superfluous high-level helpers in the backends,
+//   2) the multi-viewport / platform window implementation needs them internally.
+// Generally we avoid exposing any kind of superfluous high-level helpers in the bindings,
 // but it is too much code to duplicate everywhere so we exceptionally expose them.
 //
 // Your engine/app will likely _already_ have code to setup all that stuff (swap chain, render pass, frame buffers, etc.).

backends/imgui_impl_wgpu.cpp

@@ -4,7 +4,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -685,7 +685,7 @@ void ImGui_ImplWGPU_InvalidateDeviceObjects()
     SafeRelease(g_resources);
 
     ImGuiIO& io = ImGui::GetIO();
-    io.Fonts->SetTexID(nullptr); // We copied g_pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    io.Fonts->SetTexID(0); // We copied g_pFontTextureView to io.Fonts->TexID so let's clear that as well.
 
     for (unsigned int i = 0; i < g_numFramesInFlight; i++)
         SafeRelease(g_pFrameResources[i]);

backends/imgui_impl_wgpu.h

@@ -4,7 +4,7 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_win32.cpp

@@ -254,7 +254,8 @@ static void ImGui_ImplWin32_UpdateMouseData()
     ImGuiIO& io = ImGui::GetIO();
     IM_ASSERT(bd->hWnd != 0);
 
-    const bool is_app_focused = (::GetForegroundWindow() == bd->hWnd);
+    HWND focused_window = ::GetForegroundWindow();
+    const bool is_app_focused = (focused_window == bd->hWnd);
     if (is_app_focused)
     {
         // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
@@ -514,6 +515,7 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
     switch (msg)
     {
     case WM_MOUSEMOVE:
+    {
         // We need to call TrackMouseEvent in order to receive WM_MOUSELEAVE events
         bd->MouseHwnd = hwnd;
         if (!bd->MouseTracked)
@@ -522,8 +524,10 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
             ::TrackMouseEvent(&tme);
             bd->MouseTracked = true;
         }
-        io.AddMousePosEvent((float)GET_X_LPARAM(lParam), (float)GET_Y_LPARAM(lParam));
+        POINT mouse_pos = { (LONG)GET_X_LPARAM(lParam), (LONG)GET_Y_LPARAM(lParam) };
+        io.AddMousePosEvent((float)mouse_pos.x, (float)mouse_pos.y);
         break;
+    }
     case WM_MOUSELEAVE:
         if (bd->MouseHwnd == hwnd)
             bd->MouseHwnd = nullptr;

imgui.cpp

@@ -1864,7 +1864,7 @@ static const ImU32 GCrc32LookupTable[256] =
 // Known size hash
 // It is ok to call ImHashData on a string with known length but the ### operator won't be supported.
 // FIXME-OPT: Replace with e.g. FNV1a hash? CRC32 pretty much randomly access 1KB. Need to do proper measurements.
-ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed)
+ImGuiID ImHashData(const void* data_p, size_t data_size, ImGuiID seed)
 {
     ImU32 crc = ~seed;
     const unsigned char* data = (const unsigned char*)data_p;
@@ -1880,7 +1880,7 @@ ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed)
 // - If we reach ### in the string we discard the hash so far and reset to the seed.
 // - We don't do 'current += 2; continue;' after handling ### to keep the code smaller/faster (measured ~10% diff in Debug build)
 // FIXME-OPT: Replace with e.g. FNV1a hash? CRC32 pretty much randomly access 1KB. Need to do proper measurements.
-ImGuiID ImHashStr(const char* data_p, size_t data_size, ImU32 seed)
+ImGuiID ImHashStr(const char* data_p, size_t data_size, ImGuiID seed)
 {
     seed = ~seed;
     ImU32 crc = seed;
@@ -3374,24 +3374,26 @@ void ImGui::RenderMouseCursor(ImVec2 base_pos, float base_scale, ImGuiMouseCurso
 {
     ImGuiContext& g = *GImGui;
     IM_ASSERT(mouse_cursor > ImGuiMouseCursor_None && mouse_cursor < ImGuiMouseCursor_COUNT);
+    ImFontAtlas* font_atlas = g.DrawListSharedData.Font->ContainerAtlas;
     for (int n = 0; n < g.Viewports.Size; n++)
     {
+        // We scale cursor with current viewport/monitor, however Windows 10 for its own hardware cursor seems to be using a different scale factor.
+        ImVec2 offset, size, uv[4];
+        if (!font_atlas->GetMouseCursorTexData(mouse_cursor, &offset, &size, &uv[0], &uv[2]))
+            continue;
         ImGuiViewportP* viewport = g.Viewports[n];
+        const ImVec2 pos = base_pos - offset;
+        const float scale = base_scale;
+        if (!viewport->GetMainRect().Overlaps(ImRect(pos, pos + ImVec2(size.x + 2, size.y + 2) * scale)))
+            continue;
         ImDrawList* draw_list = GetForegroundDrawList(viewport);
-        ImFontAtlas* font_atlas = draw_list->_Data->Font->ContainerAtlas;
-        ImVec2 offset, size, uv[4];
-        if (font_atlas->GetMouseCursorTexData(mouse_cursor, &offset, &size, &uv[0], &uv[2]))
-        {
-            const ImVec2 pos = base_pos - offset;
-            const float scale = base_scale;
-            ImTextureID tex_id = font_atlas->TexID;
-            draw_list->PushTextureID(tex_id);
-            draw_list->AddImage(tex_id, pos + ImVec2(1, 0) * scale, pos + (ImVec2(1, 0) + size) * scale, uv[2], uv[3], col_shadow);
-            draw_list->AddImage(tex_id, pos + ImVec2(2, 0) * scale, pos + (ImVec2(2, 0) + size) * scale, uv[2], uv[3], col_shadow);
-            draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[2], uv[3], col_border);
-            draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[0], uv[1], col_fill);
-            draw_list->PopTextureID();
-        }
+        ImTextureID tex_id = font_atlas->TexID;
+        draw_list->PushTextureID(tex_id);
+        draw_list->AddImage(tex_id, pos + ImVec2(1, 0) * scale, pos + (ImVec2(1, 0) + size) * scale, uv[2], uv[3], col_shadow);
+        draw_list->AddImage(tex_id, pos + ImVec2(2, 0) * scale, pos + (ImVec2(2, 0) + size) * scale, uv[2], uv[3], col_shadow);
+        draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[2], uv[3], col_border);
+        draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[0], uv[1], col_fill);
+        draw_list->PopTextureID();
     }
 }
 
@@ -3886,7 +3888,7 @@ bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
             return false;
 
         // Special handling for calling after Begin() which represent the title bar or tab.
-        // When the window is collapsed (SkipItems==true) that last item will never be overwritten so we need to detect the case.
+        // 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)
             return false;
     }
@@ -4353,6 +4355,11 @@ void ImGui::NewFrame()
     g.FramerateSecPerFrameCount = ImMin(g.FramerateSecPerFrameCount + 1, IM_ARRAYSIZE(g.FramerateSecPerFrame));
     g.IO.Framerate = (g.FramerateSecPerFrameAccum > 0.0f) ? (1.0f / (g.FramerateSecPerFrameAccum / (float)g.FramerateSecPerFrameCount)) : FLT_MAX;
 
+    // Process input queue (trickle as many events as possible), turn events into writes to IO structure
+    g.InputEventsTrail.resize(0);
+    UpdateInputEvents(g.IO.ConfigInputTrickleEventQueue);
+
+    // Update viewports (after processing input queue, so io.MouseHoveredViewport is set)
     UpdateViewportsNewFrame();
 
     // Setup current font and draw list shared data
@@ -4474,10 +4481,6 @@ void ImGui::NewFrame()
     //if (g.IO.AppFocusLost)
     //    ClosePopupsExceptModals();
 
-    // Process input queue (trickle as many events as possible)
-    g.InputEventsTrail.resize(0);
-    UpdateInputEvents(g.IO.ConfigInputTrickleEventQueue);
-
     // Update keyboard input state
     UpdateKeyboardInputs();
 
@@ -5777,7 +5780,7 @@ void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar
     if (window->Collapsed)
     {
         // Title bar only
-        float backup_border_size = style.FrameBorderSize;
+        const float backup_border_size = style.FrameBorderSize;
         g.Style.FrameBorderSize = window->WindowBorderSize;
         ImU32 title_bar_col = GetColorU32((title_bar_is_highlight && !g.NavDisableHighlight) ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBgCollapsed);
         RenderFrame(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, true, window_rounding);
@@ -9983,7 +9986,7 @@ void ImGui::OpenPopupEx(ImGuiID id, ImGuiPopupFlags popup_flags)
     const int current_stack_size = g.BeginPopupStack.Size;
 
     if (popup_flags & ImGuiPopupFlags_NoOpenOverExistingPopup)
-        if (IsPopupOpen(0u, ImGuiPopupFlags_AnyPopupId))
+        if (IsPopupOpen((ImGuiID)0, ImGuiPopupFlags_AnyPopupId))
             return;
 
     ImGuiPopupData popup_ref; // Tagged as new ref as Window will be set back to NULL if we write this into OpenPopupStack.
@@ -13977,7 +13980,7 @@ void ImGui::DebugNodeTabBar(ImGuiTabBar* tab_bar, const char* label)
     {
         ImGuiTabItem* tab = &tab_bar->Tabs[tab_n];
         p += ImFormatString(p, buf_end - p, "%s'%s'",
-            tab_n > 0 ? ", " : "", (tab->NameOffset != -1) ? TabBarGetTabName(tab_bar, tab) : "???");
+            tab_n > 0 ? ", " : "", TabBarGetTabName(tab_bar, tab));
     }
     p += ImFormatString(p, buf_end - p, (tab_bar->Tabs.Size > 3) ? " ... }" : " } ");
     if (!is_active) { PushStyleColor(ImGuiCol_Text, GetStyleColorVec4(ImGuiCol_TextDisabled)); }
@@ -13999,7 +14002,7 @@ void ImGui::DebugNodeTabBar(ImGuiTabBar* tab_bar, const char* label)
             if (SmallButton("<")) { TabBarQueueReorder(tab_bar, tab, -1); } SameLine(0, 2);
             if (SmallButton(">")) { TabBarQueueReorder(tab_bar, tab, +1); } SameLine();
             Text("%02d%c Tab 0x%08X '%s' Offset: %.2f, Width: %.2f/%.2f",
-                tab_n, (tab->ID == tab_bar->SelectedTabId) ? '*' : ' ', tab->ID, (tab->NameOffset != -1) ? TabBarGetTabName(tab_bar, tab) : "???", tab->Offset, tab->Width, tab->ContentWidth);
+                tab_n, (tab->ID == tab_bar->SelectedTabId) ? '*' : ' ', tab->ID, TabBarGetTabName(tab_bar, tab), tab->Offset, tab->Width, tab->ContentWidth);
             PopID();
         }
         TreePop();

imgui_draw.cpp

@@ -389,6 +389,8 @@ void ImDrawList::_ResetForNewFrame()
     IM_STATIC_ASSERT(IM_OFFSETOF(ImDrawCmd, ClipRect) == 0);
     IM_STATIC_ASSERT(IM_OFFSETOF(ImDrawCmd, TextureId) == sizeof(ImVec4));
     IM_STATIC_ASSERT(IM_OFFSETOF(ImDrawCmd, VtxOffset) == sizeof(ImVec4) + sizeof(ImTextureID));
+    if (_Splitter._Count > 1)
+        _Splitter.Merge(this);
 
     CmdBuffer.resize(0);
     IdxBuffer.resize(0);

imgui_internal.h

@@ -318,8 +318,8 @@ namespace ImStb
 //-----------------------------------------------------------------------------
 
 // Helpers: Hashing
-IMGUI_API ImGuiID       ImHashData(const void* data, size_t data_size, ImU32 seed = 0);
-IMGUI_API ImGuiID       ImHashStr(const char* data, size_t data_size = 0, ImU32 seed = 0);
+IMGUI_API ImGuiID       ImHashData(const void* data, size_t data_size, ImGuiID seed = 0);
+IMGUI_API ImGuiID       ImHashStr(const char* data, size_t data_size = 0, ImGuiID seed = 0);
 
 // Helpers: Sorting
 #ifndef ImQsort

imgui_widgets.cpp

@@ -7660,6 +7660,7 @@ static void ImGui::TabBarLayout(ImGuiTabBar* tab_bar)
         {
             ImGuiTabItem* tab = &tab_bar->Tabs[section_tab_index + tab_n];
             tab->Offset = tab_offset;
+            tab->NameOffset = -1;
             tab_offset += tab->Width + (tab_n < section->TabCount - 1 ? g.Style.ItemInnerSpacing.x : 0.0f);
         }
         tab_bar->WidthAllTabs += ImMax(section->Width + section->Spacing, 0.0f);
@@ -7667,6 +7668,9 @@ static void ImGui::TabBarLayout(ImGuiTabBar* tab_bar)
         section_tab_index += section->TabCount;
     }
 
+    // Clear name buffers
+    tab_bar->TabsNames.Buf.resize(0);
+
     // If we have lost the selected tab, select the next most recently active one
     if (found_selected_tab_id == false)
         tab_bar->SelectedTabId = 0;
@@ -7698,10 +7702,6 @@ static void ImGui::TabBarLayout(ImGuiTabBar* tab_bar)
     tab_bar->ScrollingRectMinX = tab_bar->BarRect.Min.x + sections[0].Width + sections[0].Spacing;
     tab_bar->ScrollingRectMaxX = tab_bar->BarRect.Max.x - sections[2].Width - sections[1].Spacing;
 
-    // Clear name buffers
-    if ((tab_bar->Flags & ImGuiTabBarFlags_DockNode) == 0)
-        tab_bar->TabsNames.Buf.resize(0);
-
     // Actual layout in host window (we don't do it in BeginTabBar() so as not to waste an extra frame)
     ImGuiWindow* window = g.CurrentWindow;
     window->DC.CursorPos = tab_bar->BarRect.Min;
@@ -7759,7 +7759,9 @@ ImGuiTabItem* ImGui::TabBarGetCurrentTab(ImGuiTabBar* tab_bar)
 
 const char* ImGui::TabBarGetTabName(ImGuiTabBar* tab_bar, ImGuiTabItem* tab)
 {
-    IM_ASSERT(tab->NameOffset != -1 && tab->NameOffset < tab_bar->TabsNames.Buf.Size);
+    if (tab->NameOffset == -1)
+        return "N/A";
+    IM_ASSERT(tab->NameOffset < tab_bar->TabsNames.Buf.Size);
     return tab_bar->TabsNames.Buf.Data + tab->NameOffset;
 }