Merge branch 'master' into viewport

# Conflicts:
#	examples/imgui_impl_sdl.cpp
#	imgui.cpp

.github/CONTRIBUTING.md

@@ -14,18 +14,19 @@ You may use the Issue Tracker to submit bug reports, feature requests or suggest
 
 **Guidelines to report an issue or ask a question:**
 - Please provide your imgui version number.
-- If you are discussing an assert or a crash, please provide a debugger callstack. 
+- If you are discussing an assert or a crash, please provide a debugger callstack. Never state "it crashes" without additional information.
 - Please state if you have made substantial modifications to your copy of imgui. 
 - When discussing issues related to rendering or inputs, please state the OS/back-end/renderer you are using. Please state if you are using a vanilla copy of one of the back-end (imgui_impl_xxx files), or a modified one, or if you built your own.
+- Try to be explicit with your expectations and what you have tried. 
 - Please provide a Minimal, Complete and Verifiable Example ([MCVE](https://stackoverflow.com/help/mcve)) to demonstrate your problem. An ideal submission includes a small piece of code that anyone can paste in one of the examples/ application (e.g. in main.cpp or imgui_demo.cpp) to understand and reproduce it. Narrowing your problem to its shortest and purest form is the easiest way to understand it. Please test your shortened code to ensure it actually exhibit the problem. Often while creating the MCVE you will end up solving the problem! Many questions that are missing a standalone verifiable example are missing the actual cause of their issue in the description, which ends up wasting everyone's time.
 - Try to attach screenshots to clarify the context. They often convey useful information that are omitted by the description. You can drag pictures/files here (prefer github attachments over 3rd party hosting).
 - When requesting a new feature, please describe the usage context (how you intend to use it, why you need it, etc.).
 - Due to frequent abuse of this service from a certain category of users, if your GitHub account is anonymous and was created five minutes ago please understand that your post will receive more scrutiny and less patience for incomplete questions.
 
-If you have been using dear imgui for a while and/or have been using C/C++ for several years and/or have demonstrated good behavior here, it is ok to not fullfill every item to the letter. Those are guidelines and experienced users of dear imgui will know what information are useful in a given context.
+If you have been using dear imgui for a while or have been using C/C++ for several years or have demonstrated good behavior here, it is ok to not fullfill every item to the letter. Those are guidelines and experienced users of dear imgui will know what information are useful in a given context.
 
 ## How to create an Pull Request
-
-- If you are adding a feature, please describe the usage context (how you intend to use it, why you need it, etc.).
+- When adding a feature, please describe the usage context (how you intend to use it, why you need it, etc.).
+- When fixing a warning or compilation problem, please post the compiler log and specify the version and OS you are using.
 - Try to attach screenshots to clarify the context and demonstrate the feature at a glance. You can drag pictures/files here (prefer github attachments over 3rd party hosting).
 - Make sure you create a branch for the pull request. In Git, 1 PR is associated to 1 branch. If you keep pushing to the same branch after you submitted the PR, your new commits will appear in the PR (we can still cherry-pick individual commits).

.github/issue_template.md

@@ -13,9 +13,11 @@ SELECT "PREVIEW CHANGES" TO TURN THE URL ABOVE INTO A CLICKABLE LINK.
 
 XXX
 
-**Back-end file/Renderer/OS:** _(if the question is related to inputs/rendering/build, otherwise delete this section)_
+**Back-end file/Renderer/OS:** _(or specify if you are using a custom engine back-end)_
 
-XXX
+Back-ends: imgui_impl_XXX.cpp + imgui_impl_XXX.cpp
+OS: XXX 
+Compiler: XXX _(if the question is related to building)_
 
 **My Issue/Question:** _(please provide context)_
 

.github/pull_request_template.md

@@ -1,4 +1,5 @@
-- If you are adding a feature, please explain the context of the change: what do you need the feature for?
+- When adding a feature, please describe the usage context (how you intend to use it, why you need it, etc.).
+- When fixing a warning or compilation problem, please post the compiler log and specify the version and OS you are using.
 - Try to attach screenshots to clarify the context and demonstrate the feature at a glance.
 - Make sure you create a branch for the pull request. In Git, 1 PR is associated to 1 branch. If you keep pushing to the same branch after you submitted the PR, your new commits will appear in the PR.
 - You can read [CONTRIBUTING.md](https://github.com/ocornut/imgui/blob/master/.github/CONTRIBUTING.md) for more details.

CHANGELOG.txt

@@ -38,6 +38,7 @@ Breaking Changes:
  - Removed per-window ImGuiWindowFlags_ResizeFromAnySide beta flag in favor `io.OptResizeWindowsFromEdges=true` to enable the feature globally. (#1495)
    The feature is not currently enabled by default because it is not satisfying enough.
  - Style: Renamed ImGuiCol_ModalWindowDarkening to ImGuiCol_ModalWindowDimBg for consistency with other features. Kept redirection enum (will obsolete).
+ - Changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.
 
 Other Changes:
 
@@ -54,6 +55,7 @@ Other Changes:
  - IsItemHovered(): Added ImGuiHoveredFlags_AllowWhenDisabled flag to query hovered status on disabled items. (#1940, #211)
  - Misc: Added ImGuiMouseCursor_Hand cursor enum + corresponding software cursor. (#1913, 1914) [@aiekick, @ocornut] 
  - Misc: Tweaked software mouse cursor offset to match the offset of the corresponding Windows 10 cursors.
+ - Fixed horizontal mouse wheel not forwarding the request to the parent window if ImGuiWindowFlags_NoScrollWithMouse is set. (#1463, #1380, #1502)
  - Fixed a include build issue for Cygwin in non-POSIX (Win32) mode. (#1917, #1319, #276)
  - OS/Windows: Fixed missing ImmReleaseContext() call in the default Win32 IME handler. (#1932) [@vby]
  - Demo: Added basic Drag and Drop demo. (#143)

README.md

@@ -169,7 +169,7 @@ User screenshots:
 <br>[Gallery Part 4](https://github.com/ocornut/imgui/issues/973) (Jan 2017 to Aug 2017)
 <br>[Gallery Part 5](https://github.com/ocornut/imgui/issues/1269) (Aug 2017 to Feb 2018)
 <br>[Gallery Part 6](https://github.com/ocornut/imgui/issues/1607) (Feb 2018 onward)
-<br>[Gallery Part 6](https://github.com/ocornut/imgui/issues/1902) (June 2018 onward)
+<br>[Gallery Part 7](https://github.com/ocornut/imgui/issues/1902) (June 2018 onward)
 <br>Also see the [Mega screenshots](https://github.com/ocornut/imgui/issues/1273) for an idea of the available features.
 
 Various tools
@@ -314,6 +314,7 @@ Double-chocolate sponsors:
 - Lizardcube
 - Greggman
 - DotEmu
+- Nadeo
 
 Salty caramel supporters:
 - Jetha Chan, Wild Sheep Studio, Pastagames, Mārtiņš Možeiko, Daniel Collin, Recognition Robotics, Chris Genova, ikrima, Glenn Fiedler, Geoffrey Evans, Dakko Dakko, Mercury Labs, Singularity Demo Group, Mischa Alff, Sebastien Ronsse, Lionel Landwerlin, Nikolay Ivanov, Ron Gilbert, Brandon Townsend, Nikhil Deshpande, Cort Stratton, drudru, Harfang 3D, Supercell.

examples/example_allegro5/main.cpp

@@ -16,7 +16,7 @@ int main(int, char**)
     al_init_primitives_addon();
     al_set_new_display_flags(ALLEGRO_RESIZABLE);
     ALLEGRO_DISPLAY* display = al_create_display(1280, 720);
-    al_set_window_title(display, "ImGui Allegro 5 example");
+    al_set_window_title(display, "Dear ImGui Allegro 5 example");
     ALLEGRO_EVENT_QUEUE* queue = al_create_event_queue();
     al_register_event_source(queue, al_get_display_event_source(display));
     al_register_event_source(queue, al_get_keyboard_event_source());

examples/example_apple_opengl2/main.mm

@@ -178,7 +178,7 @@
     NSRect viewRect = NSMakeRect(100.0, 100.0, 100.0 + 1280.0, 100 + 720.0);
 	
     _window = [[NSWindow alloc] initWithContentRect:viewRect styleMask:NSWindowStyleMaskTitled|NSWindowStyleMaskMiniaturizable|NSWindowStyleMaskResizable|NSWindowStyleMaskClosable backing:NSBackingStoreBuffered defer:YES];
-    [_window setTitle:@"ImGui OSX+OpenGL2 Example"];
+    [_window setTitle:@"Dear ImGui OSX+OpenGL2 Example"];
     [_window setOpaque:YES];
     [_window makeKeyAndOrderFront:NSApp];
 	
@@ -191,8 +191,8 @@
     NSMenu* appMenu;
     NSMenuItem* menuItem;
 
-    appMenu = [[NSMenu alloc] initWithTitle:@"ImGui OSX+OpenGL2 Example"];
-    menuItem = [appMenu addItemWithTitle:@"Quit ImGui OSX+OpenGL2 Example" action:@selector(terminate:) keyEquivalent:@"q"];
+    appMenu = [[NSMenu alloc] initWithTitle:@"Dear ImGui OSX+OpenGL2 Example"];
+    menuItem = [appMenu addItemWithTitle:@"Quit Dear ImGui OSX+OpenGL2 Example" action:@selector(terminate:) keyEquivalent:@"q"];
     [menuItem setKeyEquivalentModifierMask:NSEventModifierFlagCommand];
 	
     menuItem = [[NSMenuItem alloc] init];

examples/example_freeglut_opengl2/main.cpp

@@ -88,7 +88,7 @@ int main(int argc, char** argv)
     glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_GLUTMAINLOOP_RETURNS);
     glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_MULTISAMPLE);
     glutInitWindowSize(1280, 720);
-    glutCreateWindow("ImGui FreeGLUT+OpenGL2 Example");
+    glutCreateWindow("Dear ImGui FreeGLUT+OpenGL2 Example");
 
     // Setup GLUT display function
     // We will also call ImGui_ImplFreeGLUT_InstallFuncs() to get all the other functions installed for us, 

examples/example_glfw_opengl2/main.cpp

@@ -23,7 +23,7 @@ int main(int, char**)
     glfwSetErrorCallback(glfw_error_callback);
     if (!glfwInit())
         return 1;
-    GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGui GLFW+OpenGL2 example", NULL, NULL);
+    GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+OpenGL2 example", NULL, NULL);
     if (window == NULL)
         return 1;
     glfwMakeContextCurrent(window);

examples/example_glfw_opengl3/main.cpp

@@ -45,7 +45,7 @@ int main(int, char**)
 #endif
 
     // Create window with graphics context
-    GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGui GLFW+OpenGL3 example", NULL, NULL);
+    GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+OpenGL3 example", NULL, NULL);
     if (window == NULL)
         return 1;
     glfwMakeContextCurrent(window);

examples/example_glfw_vulkan/main.cpp

@@ -318,7 +318,7 @@ int main(int, char**)
         return 1;
 
     glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API);
-    GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGui GLFW+Vulkan example", NULL, NULL);
+    GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+Vulkan example", NULL, NULL);
 
     // Setup Vulkan
     if (!glfwVulkanSupported())

examples/example_sdl_opengl2/main.cpp

@@ -30,7 +30,7 @@ int main(int, char**)
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
     SDL_DisplayMode current;
     SDL_GetCurrentDisplayMode(0, &current);
-    SDL_Window* window = SDL_CreateWindow("ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
     SDL_GL_SetSwapInterval(1); // Enable vsync
 

examples/example_sdl_opengl3/main.cpp

@@ -46,7 +46,7 @@ int main(int, char**)
     SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
     SDL_DisplayMode current;
     SDL_GetCurrentDisplayMode(0, &current);
-    SDL_Window* window = SDL_CreateWindow("ImGui SDL2+OpenGL3 example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+OpenGL3 example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
     SDL_GL_SetSwapInterval(1); // Enable vsync
     gl3wInit();

examples/example_sdl_vulkan/main.cpp

@@ -307,7 +307,7 @@ int main(int, char**)
     // Setup window
     SDL_DisplayMode current;
     SDL_GetCurrentDisplayMode(0, &current);
-    SDL_Window* window = SDL_CreateWindow("ImGui SDL2+Vulkan example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_VULKAN|SDL_WINDOW_RESIZABLE);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL2+Vulkan example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_VULKAN|SDL_WINDOW_RESIZABLE);
 
     // Setup Vulkan
     uint32_t extensions_count = 0;

examples/example_win32_directx10/main.cpp

@@ -100,7 +100,7 @@ int main(int, char**)
     // Create application window
     WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, _T("ImGui Example"), NULL };
     RegisterClassEx(&wc);
-    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("ImGui DirectX10 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
+    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("Dear ImGui DirectX10 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
 
     // Initialize Direct3D
     if (CreateDeviceD3D(hwnd) < 0)

examples/example_win32_directx11/main.cpp

@@ -116,7 +116,7 @@ int main(int, char**)
     // Create application window
     WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, _T("ImGui Example"), NULL };
     RegisterClassEx(&wc);
-    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("ImGui DirectX11 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
+    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("Dear ImGui DirectX11 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
 
     // Initialize Direct3D
     if (CreateDeviceD3D(hwnd) < 0)

examples/example_win32_directx12/main.cpp

@@ -272,7 +272,7 @@ int main(int, char**)
     // Create application window
     WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, _T("ImGui Example"), NULL };
     RegisterClassEx(&wc);
-    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("ImGui DirectX12 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
+    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("Dear ImGui DirectX12 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
 
     // Initialize Direct3D
     if (CreateDeviceD3D(hwnd) < 0)

examples/example_win32_directx9/main.cpp

@@ -49,7 +49,7 @@ int main(int, char**)
     // Create application window
     WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, NULL, NULL, NULL, _T("ImGui Example"), NULL };
     RegisterClassEx(&wc);
-    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("ImGui DirectX9 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
+    HWND hwnd = CreateWindow(_T("ImGui Example"), _T("Dear ImGui DirectX9 Example"), WS_OVERLAPPEDWINDOW, 100, 100, 1280, 800, NULL, NULL, wc.hInstance, NULL);
 
     // Initialize Direct3D
     LPDIRECT3D9 pD3D;

examples/imgui_impl_sdl.cpp

@@ -231,20 +231,19 @@ void ImGui_ImplSDL2_Shutdown()
 static void ImGui_ImplSDL2_UpdateMousePosAndButtons()
 {
     ImGuiIO& io = ImGui::GetIO();
-    const ImVec2 mouse_pos_backup = io.MousePos;
-    io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
     io.MouseHoveredViewport = 0;
 
     // Set OS mouse position if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
     // (When multi-viewports are enabled, all imgui positions are same as OS positions.)
 #if SDL_HAS_WARP_MOUSE_GLOBAL
-    if (io.WantSetMousePos)
-    {
-        if ((io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) == 0)
-            SDL_WarpMouseInWindow(g_Window, (int)mouse_pos_backup.x, (int)mouse_pos_backup.y);
-        else
-            SDL_WarpMouseGlobal((int)mouse_pos_backup.x, (int)mouse_pos_backup.y);
-    }
+    if (!io.WantSetMousePos)
+        io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
+    else if ((io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) == 0)
+        SDL_WarpMouseInWindow(g_Window, (int)io.MousePos.x, (int)io.MousePos.y);
+    else
+        SDL_WarpMouseGlobal((int)io.MousePos.x, (int)io.MousePos.y);
+#else
+    io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
 #endif
 
     int mx, my;

imgui.cpp

@@ -190,7 +190,7 @@
         io.MouseDown[1] = my_mouse_buttons[1];
 
         // Call NewFrame(), after this point you can use ImGui::* functions anytime
-        // (So you want to try calling Newframe() as early as you can in your mainloop to be able to use imgui everywhere)
+        // (So you want to try calling NewFrame() as early as you can in your mainloop to be able to use imgui everywhere)
         ImGui::NewFrame();
 
         // Most of your application code here
@@ -316,6 +316,7 @@
  - 2018/XX/XX (1.XX) - Moved IME support functions from io.ImeSetInputScreenPosFn, io.ImeWindowHandle to the PlatformIO api.
  - 2018/XX/XX (1.XX) - removed io.DisplayVisibleMin, io.DisplayVisibleMax settings (it was used to clip within the DisplayMin..DisplayMax range, I don't know of anyone using it)
 
+ - 2018/07/22 (1.63) - changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.
  - 2018/07/08 (1.63) - style: renamed ImGuiCol_ModalWindowDarkening to ImGuiCol_ModalWindowDimBg for consistency with other features. Kept redirection enum (will obsolete).
  - 2018/07/06 (1.63) - removed per-window ImGuiWindowFlags_ResizeFromAnySide beta flag in favor of a global io.OptResizeWindowsFromEdges to enable the feature.
  - 2018/06/06 (1.62) - renamed GetGlyphRangesChinese() to GetGlyphRangesChineseFull() to distinguish other variants and discourage using the full set.
@@ -900,6 +901,7 @@ static void             NavUpdateWindowingList();
 static void             NavProcessItem(ImGuiWindow* window, const ImRect& nav_bb, const ImGuiID id);
 
 static void             UpdateMouseInputs();
+static void             UpdateMouseWheel();
 static void             UpdateManualResize(ImGuiWindow* window, const ImVec2& size_auto_fit, int* border_held, int resize_grip_count, ImU32 resize_grip_col[4]);
 static void             FocusFrontMostActiveWindow(ImGuiWindow* ignore_window);
 
@@ -1847,37 +1849,41 @@ bool ImGuiTextFilter::Draw(const char* label, float width)
     return value_changed;
 }
 
-void ImGuiTextFilter::TextRange::split(char separator, ImVector<TextRange>& out)
+void ImGuiTextFilter::TextRange::split(char separator, ImVector<TextRange>* out) const
 {
-    out.resize(0);
+    out->resize(0);
     const char* wb = b;
     const char* we = wb;
     while (we < e)
     {
         if (*we == separator)
         {
-            out.push_back(TextRange(wb, we));
+            out->push_back(TextRange(wb, we));
             wb = we + 1;
         }
         we++;
     }
     if (wb != we)
-        out.push_back(TextRange(wb, we));
+        out->push_back(TextRange(wb, we));
 }
 
 void ImGuiTextFilter::Build()
 {
     Filters.resize(0);
     TextRange input_range(InputBuf, InputBuf+strlen(InputBuf));
-    input_range.split(',', Filters);
+    input_range.split(',', &Filters);
 
     CountGrep = 0;
     for (int i = 0; i != Filters.Size; i++)
     {
-        Filters[i].trim_blanks();
-        if (Filters[i].empty())
+        TextRange& f = Filters[i];
+        while (f.b < f.e && ImCharIsBlankA(f.b[0]))
+            f.b++;
+        while (f.e > f.b && ImCharIsBlankA(f.e[-1]))
+            f.e--;
+        if (f.empty())
             continue;
-        if (Filters[i].front() != '-')
+        if (Filters[i].b[0] != '-')
             CountGrep += 1;
     }
 }
@@ -1895,7 +1901,7 @@ bool ImGuiTextFilter::PassFilter(const char* text, const char* text_end) const
         const TextRange& f = Filters[i];
         if (f.empty())
             continue;
-        if (f.front() == '-')
+        if (f.b[0] == '-')
         {
             // Subtract
             if (ImStristr(text, text_end, f.begin()+1, f.end()) != NULL)
@@ -2934,7 +2940,7 @@ ImDrawData* ImGui::GetDrawData()
     return g.Viewports[0]->DrawDataP.Valid ? &g.Viewports[0]->DrawDataP : NULL;
 }
 
-float ImGui::GetTime()
+double ImGui::GetTime()
 {
     return GImGui->Time;
 }
@@ -4114,7 +4120,7 @@ static void ImGui::UpdateMouseInputs()
         g.IO.MouseDoubleClicked[i] = false;
         if (g.IO.MouseClicked[i])
         {
-            if (g.Time - g.IO.MouseClickedTime[i] < g.IO.MouseDoubleClickTime)
+            if ((float)(g.Time - g.IO.MouseClickedTime[i]) < g.IO.MouseDoubleClickTime)
             {
                 ImVec2 delta_from_click_pos = IsMousePosValid(&g.IO.MousePos) ? (g.IO.MousePos - g.IO.MouseClickedPos[i]) : ImVec2(0.0f, 0.0f);
                 if (ImLengthSqr(delta_from_click_pos) < g.IO.MouseDoubleClickMaxDist * g.IO.MouseDoubleClickMaxDist)
@@ -4142,6 +4148,51 @@ static void ImGui::UpdateMouseInputs()
     }
 }
 
+void ImGui::UpdateMouseWheel()
+{
+    ImGuiContext& g = *GImGui;
+    if (!g.HoveredWindow || g.HoveredWindow->Collapsed)
+        return;
+    if (g.IO.MouseWheel == 0.0f && g.IO.MouseWheelH == 0.0f)
+        return;
+
+    // If a child window has the ImGuiWindowFlags_NoScrollWithMouse flag, we give a chance to scroll its parent (unless either ImGuiWindowFlags_NoInputs or ImGuiWindowFlags_NoScrollbar are also set).
+    ImGuiWindow* window = g.HoveredWindow;
+    ImGuiWindow* scroll_window = window;
+    while ((scroll_window->Flags & ImGuiWindowFlags_ChildWindow) && (scroll_window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(scroll_window->Flags & ImGuiWindowFlags_NoScrollbar) && !(scroll_window->Flags & ImGuiWindowFlags_NoInputs) && scroll_window->ParentWindow)
+        scroll_window = scroll_window->ParentWindow;
+    const bool scroll_allowed = !(scroll_window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(scroll_window->Flags & ImGuiWindowFlags_NoInputs);
+
+    if (g.IO.MouseWheel != 0.0f)
+    {
+        if (g.IO.KeyCtrl && g.IO.FontAllowUserScaling)
+        {
+            // Zoom / Scale window
+            const float new_font_scale = ImClamp(window->FontWindowScale + g.IO.MouseWheel * 0.10f, 0.50f, 2.50f);
+            const float scale = new_font_scale / window->FontWindowScale;
+            window->FontWindowScale = new_font_scale;
+
+            const ImVec2 offset = window->Size * (1.0f - scale) * (g.IO.MousePos - window->Pos) / window->Size;
+            window->Pos += offset;
+            window->Size *= scale;
+            window->SizeFull *= scale;
+        }
+        else if (!g.IO.KeyCtrl && scroll_allowed)
+        {
+            // Mouse wheel vertical scrolling
+            float scroll_amount = 5 * scroll_window->CalcFontSize();
+            scroll_amount = (float)(int)ImMin(scroll_amount, (scroll_window->ContentsRegionRect.GetHeight() + scroll_window->WindowPadding.y * 2.0f) * 0.67f);
+            SetWindowScrollY(scroll_window, scroll_window->Scroll.y - g.IO.MouseWheel * scroll_amount);
+        }
+    }
+    if (g.IO.MouseWheelH != 0.0f && scroll_allowed && !g.IO.KeyCtrl)
+    {
+        // Mouse wheel horizontal scrolling (for hardware that supports it)
+        float scroll_amount = scroll_window->CalcFontSize();
+        SetWindowScrollX(scroll_window, scroll_window->Scroll.x - g.IO.MouseWheelH * scroll_amount);
+    }
+}
+
 // The reason this is exposed in imgui_internal.h is: on touch-based system that don't have hovering, we want to dispatch inputs to the right target (imgui vs imgui+app)
 void ImGui::UpdateHoveredWindowAndCaptureFlags()
 {
@@ -4288,8 +4339,9 @@ void ImGui::NewFrame()
 
     UpdateViewports();
 
-    // Setup font, draw list shared data
+    // Setup current font, and draw list shared data
     // FIXME-VIEWPORT: the concept of a single ClipRectFullscreen is not ideal!
+    g.IO.Fonts->Locked = true;
     SetCurrentFont(GetDefaultFont());
     IM_ASSERT(g.Font->IsLoaded());
     ImVec2 virtual_space_max(0,0);
@@ -4373,45 +4425,7 @@ void ImGui::NewFrame()
     g.PlatformImePosViewport = NULL;
 
     // Mouse wheel scrolling, scale
-    if (g.HoveredWindow && !g.HoveredWindow->Collapsed && (g.IO.MouseWheel != 0.0f || g.IO.MouseWheelH != 0.0f))
-    {
-        // If a child window has the ImGuiWindowFlags_NoScrollWithMouse flag, we give a chance to scroll its parent (unless either ImGuiWindowFlags_NoInputs or ImGuiWindowFlags_NoScrollbar are also set).
-        ImGuiWindow* window = g.HoveredWindow;
-        ImGuiWindow* scroll_window = window;
-        while ((scroll_window->Flags & ImGuiWindowFlags_ChildWindow) && (scroll_window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(scroll_window->Flags & ImGuiWindowFlags_NoScrollbar) && !(scroll_window->Flags & ImGuiWindowFlags_NoInputs) && scroll_window->ParentWindow)
-            scroll_window = scroll_window->ParentWindow;
-        const bool scroll_allowed = !(scroll_window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(scroll_window->Flags & ImGuiWindowFlags_NoInputs);
-
-        if (g.IO.MouseWheel != 0.0f)
-        {
-            if (g.IO.KeyCtrl && g.IO.FontAllowUserScaling)
-            {
-                // Zoom / Scale window
-                const float new_font_scale = ImClamp(window->FontWindowScale + g.IO.MouseWheel * 0.10f, 0.50f, 2.50f);
-                const float scale = new_font_scale / window->FontWindowScale;
-                window->FontWindowScale = new_font_scale;
-
-                const ImVec2 offset = window->Size * (1.0f - scale) * (g.IO.MousePos - window->Pos) / window->Size;
-                window->Pos += offset;
-                window->Size *= scale;
-                window->SizeFull *= scale;
-            }
-            else if (!g.IO.KeyCtrl && scroll_allowed)
-            {
-                // Mouse wheel vertical scrolling
-                float scroll_amount = 5 * scroll_window->CalcFontSize();
-                scroll_amount = (float)(int)ImMin(scroll_amount, (scroll_window->ContentsRegionRect.GetHeight() + scroll_window->WindowPadding.y * 2.0f) * 0.67f);
-                SetWindowScrollY(scroll_window, scroll_window->Scroll.y - g.IO.MouseWheel * scroll_amount);
-            }
-        }
-        if (g.IO.MouseWheelH != 0.0f && scroll_allowed)
-        {
-            // Mouse wheel horizontal scrolling (for hardware that supports it)
-            float scroll_amount = scroll_window->CalcFontSize();
-            if (!g.IO.KeyCtrl && !(window->Flags & ImGuiWindowFlags_NoScrollWithMouse))
-                SetWindowScrollX(window, window->Scroll.x - g.IO.MouseWheelH * scroll_amount);
-        }
-    }
+    UpdateMouseWheel();
 
     // Pressing TAB activate widget focus
     if (g.ActiveId == 0 && g.NavWindow != NULL && g.NavWindow->Active && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs) && !g.IO.KeyCtrl && IsKeyPressedMap(ImGuiKey_Tab, false))
@@ -5015,6 +5029,9 @@ void ImGui::EndFrame()
     IM_ASSERT(g.Windows.Size == g.WindowsSortBuffer.Size);  // we done something wrong
     g.Windows.swap(g.WindowsSortBuffer);
 
+    // Unlock font atlas
+    g.IO.Fonts->Locked = false;
+
     // Clear Input data for next frame
     g.IO.MouseWheel = g.IO.MouseWheelH = 0.0f;
     memset(g.IO.InputCharacters, 0, sizeof(g.IO.InputCharacters));
@@ -5378,11 +5395,23 @@ void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
     }
 }
 
-// Render a triangle to denote expanded/collapsed state
+// Render an arrow. 'pos' is position of the arrow tip. half_sz.x is length from base to tip. half_sz.y is length on each side.
+void ImGui::RenderArrowPointingAt(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, ImGuiDir direction, ImU32 col)
+{
+    switch (direction)
+    {
+    case ImGuiDir_Left:  draw_list->AddTriangleFilled(ImVec2(pos.x + half_sz.x, pos.y - half_sz.y), ImVec2(pos.x + half_sz.x, pos.y + half_sz.y), pos, col); return;
+    case ImGuiDir_Right: draw_list->AddTriangleFilled(ImVec2(pos.x - half_sz.x, pos.y + half_sz.y), ImVec2(pos.x - half_sz.x, pos.y - half_sz.y), pos, col); return;
+    case ImGuiDir_Up:    draw_list->AddTriangleFilled(ImVec2(pos.x + half_sz.x, pos.y + half_sz.y), ImVec2(pos.x - half_sz.x, pos.y + half_sz.y), pos, col); return;
+    case ImGuiDir_Down:  draw_list->AddTriangleFilled(ImVec2(pos.x - half_sz.x, pos.y - half_sz.y), ImVec2(pos.x + half_sz.x, pos.y - half_sz.y), pos, col); return;
+    case ImGuiDir_None: case ImGuiDir_COUNT: break; // Fix warnings
+    }
+}
+
+// Render an arrow aimed to be aligned with text (p_min is a position in the same space text would be positioned). To e.g. denote expanded/collapsed state
 void ImGui::RenderArrow(ImVec2 p_min, ImGuiDir dir, float scale)
 {
     ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
 
     const float h = g.FontSize * 1.00f;
     float r = h * 0.40f * scale;
@@ -5394,18 +5423,16 @@ void ImGui::RenderArrow(ImVec2 p_min, ImGuiDir dir, float scale)
     case ImGuiDir_Up:
     case ImGuiDir_Down:
         if (dir == ImGuiDir_Up) r = -r;
-        center.y -= r * 0.25f;
-        a = ImVec2(0,1) * r;
-        b = ImVec2(-0.866f,-0.5f) * r;
-        c = ImVec2(+0.866f,-0.5f) * r;
+        a = ImVec2(+0.000f,+0.750f) * r;
+        b = ImVec2(-0.866f,-0.750f) * r;
+        c = ImVec2(+0.866f,-0.750f) * r;
         break;
     case ImGuiDir_Left:
     case ImGuiDir_Right:
         if (dir == ImGuiDir_Left) r = -r;
-        center.x -= r * 0.25f;
-        a = ImVec2(1,0) * r;
-        b = ImVec2(-0.500f,+0.866f) * r;
-        c = ImVec2(-0.500f,-0.866f) * r;
+        a = ImVec2(+0.750f,+0.000f) * r;
+        b = ImVec2(-0.750f,+0.866f) * r;
+        c = ImVec2(-0.750f,-0.866f) * r;
         break;
     case ImGuiDir_None:
     case ImGuiDir_COUNT:
@@ -5413,7 +5440,7 @@ void ImGui::RenderArrow(ImVec2 p_min, ImGuiDir dir, float scale)
         break;
     }
 
-    window->DrawList->AddTriangleFilled(center + a, center + b, center + c, GetColorU32(ImGuiCol_Text));
+    g.CurrentWindow->DrawList->AddTriangleFilled(center + a, center + b, center + c, GetColorU32(ImGuiCol_Text));
 }
 
 void ImGui::RenderBullet(ImVec2 pos)
@@ -7601,15 +7628,8 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
 
             // Collapse button
             if (!(flags & ImGuiWindowFlags_NoCollapse))
-            {
-                ImGuiID id = window->GetID("#COLLAPSE");
-                ImRect bb(window->Pos + style.FramePadding + ImVec2(1,1), window->Pos + style.FramePadding + ImVec2(g.FontSize,g.FontSize) - ImVec2(1,1));
-                ItemAdd(bb, id);
-                if (ButtonBehavior(bb, id, NULL, NULL))
+                if (CollapseButton(window->GetID("#COLLAPSE"), window->Pos + style.FramePadding))
                     window->CollapseToggleWanted = true; // Defer collapsing to next frame as we are too far in the Begin() function
-                RenderNavHighlight(bb, id);
-                RenderArrow(window->Pos + style.FramePadding, window->Collapsed ? ImGuiDir_Right : ImGuiDir_Down, 1.0f);
-            }
 
             // Close button
             if (p_open != NULL)
@@ -9320,6 +9340,24 @@ bool ImGui::CloseButton(ImGuiID id, const ImVec2& pos, float radius)
     return pressed;
 }
 
+bool ImGui::CollapseButton(ImGuiID id, const ImVec2& pos)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    ImRect bb(pos, pos + ImVec2(g.FontSize, g.FontSize));
+    ItemAdd(bb, id);
+    bool ret = ButtonBehavior(bb, id, NULL, NULL, ImGuiButtonFlags_None);
+    RenderNavHighlight(bb, id);
+    RenderArrow(bb.Min, window->Collapsed ? ImGuiDir_Right : ImGuiDir_Down, 1.0f);
+
+    // Switch to moving the window after mouse is moved beyond the initial drag threshold
+    if (IsItemActive() && IsMouseDragging())
+        StartMouseMovingWindow(window);
+
+    return ret;
+}
+
 void ImGui::Image(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, const ImVec4& tint_col, const ImVec4& border_col)
 {
     ImGuiWindow* window = GetCurrentWindow();
@@ -13548,25 +13586,12 @@ bool ImGui::ColorPicker3(const char* label, float col[3], ImGuiColorEditFlags fl
     return true;
 }
 
-// 'pos' is position of the arrow tip. half_sz.x is length from base to tip. half_sz.y is length on each side.
-static void RenderArrow(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, ImGuiDir direction, ImU32 col)
-{
-    switch (direction)
-    {
-    case ImGuiDir_Left:  draw_list->AddTriangleFilled(ImVec2(pos.x + half_sz.x, pos.y - half_sz.y), ImVec2(pos.x + half_sz.x, pos.y + half_sz.y), pos, col); return;
-    case ImGuiDir_Right: draw_list->AddTriangleFilled(ImVec2(pos.x - half_sz.x, pos.y + half_sz.y), ImVec2(pos.x - half_sz.x, pos.y - half_sz.y), pos, col); return;
-    case ImGuiDir_Up:    draw_list->AddTriangleFilled(ImVec2(pos.x + half_sz.x, pos.y + half_sz.y), ImVec2(pos.x - half_sz.x, pos.y + half_sz.y), pos, col); return;
-    case ImGuiDir_Down:  draw_list->AddTriangleFilled(ImVec2(pos.x - half_sz.x, pos.y - half_sz.y), ImVec2(pos.x + half_sz.x, pos.y - half_sz.y), pos, col); return;
-    case ImGuiDir_None: case ImGuiDir_COUNT: break; // Fix warnings
-    }
-}
-
 static void RenderArrowsForVerticalBar(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, float bar_w)
 {
-    RenderArrow(draw_list, ImVec2(pos.x + half_sz.x + 1,         pos.y), ImVec2(half_sz.x + 2, half_sz.y + 1), ImGuiDir_Right, IM_COL32_BLACK);
-    RenderArrow(draw_list, ImVec2(pos.x + half_sz.x,             pos.y), half_sz,                              ImGuiDir_Right, IM_COL32_WHITE);
-    RenderArrow(draw_list, ImVec2(pos.x + bar_w - half_sz.x - 1, pos.y), ImVec2(half_sz.x + 2, half_sz.y + 1), ImGuiDir_Left,  IM_COL32_BLACK);
-    RenderArrow(draw_list, ImVec2(pos.x + bar_w - half_sz.x,     pos.y), half_sz,                              ImGuiDir_Left,  IM_COL32_WHITE);
+    ImGui::RenderArrowPointingAt(draw_list, ImVec2(pos.x + half_sz.x + 1,         pos.y), ImVec2(half_sz.x + 2, half_sz.y + 1), ImGuiDir_Right, IM_COL32_BLACK);
+    ImGui::RenderArrowPointingAt(draw_list, ImVec2(pos.x + half_sz.x,             pos.y), half_sz,                              ImGuiDir_Right, IM_COL32_WHITE);
+    ImGui::RenderArrowPointingAt(draw_list, ImVec2(pos.x + bar_w - half_sz.x - 1, pos.y), ImVec2(half_sz.x + 2, half_sz.y + 1), ImGuiDir_Left,  IM_COL32_BLACK);
+    ImGui::RenderArrowPointingAt(draw_list, ImVec2(pos.x + bar_w - half_sz.x,     pos.y), half_sz,                              ImGuiDir_Left,  IM_COL32_WHITE);
 }
 
 // ColorPicker

imgui.h

@@ -37,7 +37,7 @@
 
 // Helpers
 #ifndef IM_ASSERT
-#include <assert.h>                                                             
+#include <assert.h>
 #define IM_ASSERT(_EXPR)            assert(_EXPR)                               // You can override the default assert handler by editing imconfig.h
 #endif
 #if defined(__clang__) || defined(__GNUC__)
@@ -53,6 +53,9 @@
 #if defined(__clang__)
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wold-style-cast"
+#elif defined(__GNUC__) && __GNUC__ >= 8
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wclass-memaccess"
 #endif
 
 // Forward declarations
@@ -530,7 +533,7 @@ namespace ImGui
     IMGUI_API void          SetItemAllowOverlap();                                              // allow last item to be overlapped by a subsequent item. sometimes useful with invisible buttons, selectables, etc. to catch unused area.
     IMGUI_API bool          IsRectVisible(const ImVec2& size);                                  // test if rectangle (of given size, starting from cursor position) is visible / not clipped.
     IMGUI_API bool          IsRectVisible(const ImVec2& rect_min, const ImVec2& rect_max);      // test if rectangle (in screen space) is visible / not clipped. to perform coarse clipping on user's side.
-    IMGUI_API float         GetTime();
+    IMGUI_API double        GetTime();
     IMGUI_API int           GetFrameCount();
     IMGUI_API ImDrawList*   GetOverlayDrawList();                                               // this draw list will be the last rendered. it covers the entire current viewport. useful to quickly draw overlays shapes/text
     IMGUI_API ImDrawListSharedData* GetDrawListSharedData();                                    // you may use this when creating your own ImDrawList instances
@@ -1182,7 +1185,7 @@ struct ImGuiIO
 
     ImVec2      MousePosPrev;               // Previous mouse position temporary storage (nb: not for public use, set to MousePos in NewFrame())
     ImVec2      MouseClickedPos[5];         // Position at time of clicking
-    float       MouseClickedTime[5];        // Time of last click (used to figure out double-click)
+    double      MouseClickedTime[5];        // Time of last click (used to figure out double-click)
     bool        MouseClicked[5];            // Mouse button went from !Down to Down
     bool        MouseDoubleClicked[5];      // Has mouse button been double-clicked?
     bool        MouseReleased[5];           // Mouse button went from Down to !Down
@@ -1332,6 +1335,14 @@ struct ImGuiOnceUponAFrame
 // Helper: Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
 struct ImGuiTextFilter
 {
+    IMGUI_API           ImGuiTextFilter(const char* default_filter = "");
+    IMGUI_API bool      Draw(const char* label = "Filter (inc,-exc)", float width = 0.0f);    // Helper calling InputText+Build
+    IMGUI_API bool      PassFilter(const char* text, const char* text_end = NULL) const;
+    IMGUI_API void      Build();
+    void                Clear()          { InputBuf[0] = 0; Build(); }
+    bool                IsActive() const { return !Filters.empty(); }
+
+    // [Internal]
     struct TextRange
     {
         const char* b;
@@ -1339,25 +1350,14 @@ struct ImGuiTextFilter
 
         TextRange() { b = e = NULL; }
         TextRange(const char* _b, const char* _e) { b = _b; e = _e; }
-        const char* begin() const { return b; }
-        const char* end() const { return e; }
-        bool empty() const { return b == e; }
-        char front() const { return *b; }
-        static bool is_blank(char c) { return c == ' ' || c == '\t'; }
-        void trim_blanks() { while (b < e && is_blank(*b)) b++; while (e > b && is_blank(*(e-1))) e--; }
-        IMGUI_API void split(char separator, ImVector<TextRange>& out);
+        const char*     begin() const   { return b; }
+        const char*     end () const    { return e; }
+        bool            empty() const   { return b == e; }
+        IMGUI_API void  split(char separator, ImVector<TextRange>* out) const;
     };
-
     char                InputBuf[256];
     ImVector<TextRange> Filters;
     int                 CountGrep;
-
-    IMGUI_API           ImGuiTextFilter(const char* default_filter = "");
-    IMGUI_API bool      Draw(const char* label = "Filter (inc,-exc)", float width = 0.0f);    // Helper calling InputText+Build
-    IMGUI_API bool      PassFilter(const char* text, const char* text_end = NULL) const;
-    IMGUI_API void      Build();
-    void                Clear() { InputBuf[0] = 0; Build(); }
-    bool                IsActive() const { return !Filters.empty(); }
 };
 
 // Helper: Text buffer for logging/accumulating text
@@ -1875,6 +1875,7 @@ struct ImFontAtlas
     // Members
     //-------------------------------------------
 
+    bool                        Locked;             // Marked as Locked by ImGui::NewFrame() so attempt to modify the atlas will assert.
     ImFontAtlasFlags            Flags;              // Build flags (see ImFontAtlasFlags_)
     ImTextureID                 TexID;              // User data to refer to the texture once it has been uploaded to user's graphic systems. It is passed back to you during rendering via the ImDrawCmd structure.
     int                         TexDesiredWidth;    // Texture width desired by user before Build(). Must be a power-of-two. If have many glyphs your graphics API have texture size restrictions you may want to increase texture width to decrease height.
@@ -2050,6 +2051,8 @@ struct ImGuiViewport
 
 #if defined(__clang__)
 #pragma clang diagnostic pop
+#elif defined(__GNUC__) && __GNUC__ >= 8
+#pragma GCC diagnostic pop
 #endif
 
 // Include imgui_user.h at the end of imgui.h (convenient for user to only explicitly include vanilla imgui.h)

imgui_demo.cpp

@@ -820,7 +820,7 @@ void ImGui::ShowDemoWindow(bool* p_open)
             // Tip: If your float aren't contiguous but part of a structure, you can pass a pointer to your first float and the sizeof() of your structure in the Stride parameter.
             static float values[90] = { 0 };
             static int values_offset = 0;
-            static float refresh_time = 0.0f;
+            static double refresh_time = 0.0;
             if (!animate || refresh_time == 0.0f)
                 refresh_time = ImGui::GetTime();
             while (refresh_time < ImGui::GetTime()) // Create dummy data at fixed 60 hz rate for the demo
@@ -3021,8 +3021,8 @@ static void ShowExampleAppLog(bool* p_open)
     static ExampleAppLog log;
 
     // Demo: add random items (unless Ctrl is held)
-    static float last_time = -1.0f;
-    float time = ImGui::GetTime();
+    static double last_time = -1.0;
+    double time = ImGui::GetTime();
     if (time - last_time >= 0.20f && !ImGui::GetIO().KeyCtrl)
     {
         const char* random_words[] = { "system", "info", "warning", "error", "fatal", "notice", "log" };

imgui_draw.cpp

@@ -1378,6 +1378,7 @@ static const ImVec2 FONT_ATLAS_DEFAULT_TEX_CURSOR_DATA[ImGuiMouseCursor_COUNT][3
 
 ImFontAtlas::ImFontAtlas()
 {
+    Locked = false;
     Flags = 0x00;
     TexID = NULL;
     TexDesiredWidth = 0;
@@ -1394,11 +1395,13 @@ ImFontAtlas::ImFontAtlas()
 
 ImFontAtlas::~ImFontAtlas()
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     Clear();
 }
 
 void    ImFontAtlas::ClearInputData()
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     for (int i = 0; i < ConfigData.Size; i++)
         if (ConfigData[i].FontData && ConfigData[i].FontDataOwnedByAtlas)
         {
@@ -1421,6 +1424,7 @@ void    ImFontAtlas::ClearInputData()
 
 void    ImFontAtlas::ClearTexData()
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     if (TexPixelsAlpha8)
         ImGui::MemFree(TexPixelsAlpha8);
     if (TexPixelsRGBA32)
@@ -1431,6 +1435,7 @@ void    ImFontAtlas::ClearTexData()
 
 void    ImFontAtlas::ClearFonts()
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     for (int i = 0; i < Fonts.Size; i++)
         IM_DELETE(Fonts[i]);
     Fonts.clear();
@@ -1485,6 +1490,7 @@ void    ImFontAtlas::GetTexDataAsRGBA32(unsigned char** out_pixels, int* out_wid
 
 ImFont* ImFontAtlas::AddFont(const ImFontConfig* font_cfg)
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     IM_ASSERT(font_cfg->FontData != NULL && font_cfg->FontDataSize > 0);
     IM_ASSERT(font_cfg->SizePixels > 0.0f);
 
@@ -1546,6 +1552,7 @@ ImFont* ImFontAtlas::AddFontDefault(const ImFontConfig* font_cfg_template)
 
 ImFont* ImFontAtlas::AddFontFromFileTTF(const char* filename, float size_pixels, const ImFontConfig* font_cfg_template, const ImWchar* glyph_ranges)
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     size_t data_size = 0;
     void* data = ImFileLoadToMemory(filename, "rb", &data_size, 0);
     if (!data)
@@ -1567,6 +1574,7 @@ ImFont* ImFontAtlas::AddFontFromFileTTF(const char* filename, float size_pixels,
 // NB: Transfer ownership of 'ttf_data' to ImFontAtlas, unless font_cfg_template->FontDataOwnedByAtlas == false. Owned TTF buffer will be deleted after Build().
 ImFont* ImFontAtlas::AddFontFromMemoryTTF(void* ttf_data, int ttf_size, float size_pixels, const ImFontConfig* font_cfg_template, const ImWchar* glyph_ranges)
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     ImFontConfig font_cfg = font_cfg_template ? *font_cfg_template : ImFontConfig();
     IM_ASSERT(font_cfg.FontData == NULL);
     font_cfg.FontData = ttf_data;
@@ -1660,6 +1668,7 @@ bool ImFontAtlas::GetMouseCursorTexData(ImGuiMouseCursor cursor_type, ImVec2* ou
 
 bool    ImFontAtlas::Build()
 {
+    IM_ASSERT(!Locked && "Cannot modify a locked ImFontAtlas between NewFrame() and EndFrame/Render()!");
     return ImFontAtlasBuildWithStbTruetype(this);
 }
 

imgui_internal.h

@@ -652,7 +652,7 @@ struct ImGuiContext
     float                   FontBaseSize;                       // (Shortcut) == IO.FontGlobalScale * Font->Scale * Font->FontSize. Base text height.
     ImDrawListSharedData    DrawListSharedData;
 
-    float                   Time;
+    double                  Time;
     int                     FrameCount;
     int                     FrameCountEnded;
     int                     FrameCountPlatformEnded;
@@ -1228,6 +1228,7 @@ namespace ImGui
     IMGUI_API void          RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding = 0.0f);
     IMGUI_API void          RenderColorRectWithAlphaCheckerboard(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, float grid_step, ImVec2 grid_off, float rounding = 0.0f, int rounding_corners_flags = ~0);
     IMGUI_API void          RenderArrow(ImVec2 pos, ImGuiDir dir, float scale = 1.0f);
+    IMGUI_API void          RenderArrowPointingAt(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, ImGuiDir direction, ImU32 col);
     IMGUI_API void          RenderBullet(ImVec2 pos);
     IMGUI_API void          RenderCheckMark(ImVec2 pos, ImU32 col, float sz);
     IMGUI_API void          RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFlags flags = ImGuiNavHighlightFlags_TypeDefault); // Navigation highlight
@@ -1237,6 +1238,7 @@ namespace ImGui
     IMGUI_API bool          ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool* out_held, ImGuiButtonFlags flags = 0);
     IMGUI_API bool          ButtonEx(const char* label, const ImVec2& size_arg = ImVec2(0,0), ImGuiButtonFlags flags = 0);
     IMGUI_API bool          CloseButton(ImGuiID id, const ImVec2& pos, float radius);
+    IMGUI_API bool          CollapseButton(ImGuiID id, const ImVec2& pos);
     IMGUI_API bool          ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size_arg, ImGuiButtonFlags flags);
 
     IMGUI_API bool          DragBehavior(ImGuiID id, ImGuiDataType data_type, void* v, float v_speed, const void* v_min, const void* v_max, const char* format, float power);