Initial setup

1 files changed, 374 insertions, 0 deletions

diff --git a/3rdparty/imgui/backend/imgui_impl_glfw.cpp b/3rdparty/imgui/backend/imgui_impl_glfw.cpp
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+++ b/3rdparty/imgui/backend/imgui_impl_glfw.cpp
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+// 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+)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange' (note: the resizing cursors requires GLFW 3.4+).
+//  [X] Platform: Keyboard arrays indexed using GLFW_KEY_* codes, e.g. ImGui::IsKeyPressed(GLFW_KEY_SPACE).
+
+// 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.
+// Read online: https://github.com/ocornut/imgui/tree/master/docs
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2020-01-17: Inputs: Disable error callback while assigning mouse cursors because some X11 setup don't have them and it generates errors.
+//  2019-12-05: Inputs: Added support for new mouse cursors added in GLFW 3.4+ (resizing cursors, not allowed cursor).
+//  2019-10-18: Misc: Previously installed user callbacks are now restored on shutdown.
+//  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
+//  2019-05-11: Inputs: Don't filter value from character callback before calling AddInputCharacter().
+//  2019-03-12: Misc: Preserve DisplayFramebufferScale when main window is minimized.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-11-07: Inputs: When installing our GLFW callbacks, we save user's previously installed ones - if any - and chain call them.
+//  2018-08-01: Inputs: Workaround for Emscripten which doesn't seem to handle focus related calls.
+//  2018-06-29: Inputs: Added support for the ImGuiMouseCursor_Hand cursor.
+//  2018-06-08: Misc: Extracted imgui_impl_glfw.cpp/.h away from the old combined GLFW+OpenGL/Vulkan examples.
+//  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-02-20: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value, passed to glfwSetCursor()).
+//  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
+//  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.
+//  2018-01-25: Inputs: Added gamepad support if ImGuiConfigFlags_NavEnableGamepad is set.
+//  2018-01-25: Inputs: Honoring the io.WantSetMousePos by repositioning the mouse (when using navigation and ImGuiConfigFlags_NavMoveMouse is set).
+//  2018-01-20: Inputs: Added Horizontal Mouse Wheel support.
+//  2018-01-18: Inputs: Added mapping for ImGuiKey_Insert.
+//  2017-08-25: Inputs: MousePos set to -FLT_MAX,-FLT_MAX when mouse is unavailable/missing (instead of -1,-1).
+//  2016-10-15: Misc: Added a void* user_data parameter to Clipboard function handlers.
+
+#include "imgui.h"
+#include "imgui_impl_glfw.h"
+
+// GLFW
+#include <GLFW/glfw3.h>
+#ifdef _WIN32
+#undef APIENTRY
+#define GLFW_EXPOSE_NATIVE_WIN32
+#include <GLFW/glfw3native.h>   // for glfwGetWin32Window
+#endif
+#define GLFW_HAS_WINDOW_TOPMOST       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ GLFW_FLOATING
+#define GLFW_HAS_WINDOW_HOVERED       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ GLFW_HOVERED
+#define GLFW_HAS_WINDOW_ALPHA         (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwSetWindowOpacity
+#define GLFW_HAS_PER_MONITOR_DPI      (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwGetMonitorContentScale
+#define GLFW_HAS_VULKAN               (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ glfwCreateWindowSurface
+#ifdef GLFW_RESIZE_NESW_CURSOR  // let's be nice to people who pulled GLFW between 2019-04-16 (3.4 define) and 2019-11-29 (cursors defines) // FIXME: Remove when GLFW 3.4 is released?
+#define GLFW_HAS_NEW_CURSORS          (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3400) // 3.4+ GLFW_RESIZE_ALL_CURSOR, GLFW_RESIZE_NESW_CURSOR, GLFW_RESIZE_NWSE_CURSOR, GLFW_NOT_ALLOWED_CURSOR
+#else
+#define GLFW_HAS_NEW_CURSORS          (0)
+#endif
+
+// Data
+enum GlfwClientApi
+{
+    GlfwClientApi_Unknown,
+    GlfwClientApi_OpenGL,
+    GlfwClientApi_Vulkan
+};
+static GLFWwindow*          g_Window = NULL;    // Main window
+static GlfwClientApi        g_ClientApi = GlfwClientApi_Unknown;
+static double               g_Time = 0.0;
+static bool                 g_MouseJustPressed[ImGuiMouseButton_COUNT] = {};
+static GLFWcursor*          g_MouseCursors[ImGuiMouseCursor_COUNT] = {};
+static bool                 g_InstalledCallbacks = false;
+
+// Chain GLFW callbacks: our callbacks will call the user's previously installed callbacks, if any.
+static GLFWmousebuttonfun   g_PrevUserCallbackMousebutton = NULL;
+static GLFWscrollfun        g_PrevUserCallbackScroll = NULL;
+static GLFWkeyfun           g_PrevUserCallbackKey = NULL;
+static GLFWcharfun          g_PrevUserCallbackChar = NULL;
+
+static const char* ImGui_ImplGlfw_GetClipboardText(void* user_data)
+{
+    return glfwGetClipboardString((GLFWwindow*)user_data);
+}
+
+static void ImGui_ImplGlfw_SetClipboardText(void* user_data, const char* text)
+{
+    glfwSetClipboardString((GLFWwindow*)user_data, text);
+}
+
+void ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods)
+{
+    if (g_PrevUserCallbackMousebutton != NULL)
+        g_PrevUserCallbackMousebutton(window, button, action, mods);
+
+    if (action == GLFW_PRESS && button >= 0 && button < IM_ARRAYSIZE(g_MouseJustPressed))
+        g_MouseJustPressed[button] = true;
+}
+
+void ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset)
+{
+    if (g_PrevUserCallbackScroll != NULL)
+        g_PrevUserCallbackScroll(window, xoffset, yoffset);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.MouseWheelH += (float)xoffset;
+    io.MouseWheel += (float)yoffset;
+}
+
+void ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods)
+{
+    if (g_PrevUserCallbackKey != NULL)
+        g_PrevUserCallbackKey(window, key, scancode, action, mods);
+
+    ImGuiIO& io = ImGui::GetIO();
+    if (action == GLFW_PRESS)
+        io.KeysDown[key] = true;
+    if (action == GLFW_RELEASE)
+        io.KeysDown[key] = false;
+
+    // Modifiers are not reliable across systems
+    io.KeyCtrl = io.KeysDown[GLFW_KEY_LEFT_CONTROL] || io.KeysDown[GLFW_KEY_RIGHT_CONTROL];
+    io.KeyShift = io.KeysDown[GLFW_KEY_LEFT_SHIFT] || io.KeysDown[GLFW_KEY_RIGHT_SHIFT];
+    io.KeyAlt = io.KeysDown[GLFW_KEY_LEFT_ALT] || io.KeysDown[GLFW_KEY_RIGHT_ALT];
+#ifdef _WIN32
+    io.KeySuper = false;
+#else
+    io.KeySuper = io.KeysDown[GLFW_KEY_LEFT_SUPER] || io.KeysDown[GLFW_KEY_RIGHT_SUPER];
+#endif
+}
+
+void ImGui_ImplGlfw_CharCallback(GLFWwindow* window, unsigned int c)
+{
+    if (g_PrevUserCallbackChar != NULL)
+        g_PrevUserCallbackChar(window, c);
+
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddInputCharacter(c);
+}
+
+static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, GlfwClientApi client_api)
+{
+    g_Window = window;
+    g_Time = 0.0;
+
+    // Setup backend capabilities flags
+    ImGuiIO& io = ImGui::GetIO();
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;         // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+    io.BackendPlatformName = "imgui_impl_glfw";
+
+    // Keyboard mapping. Dear ImGui will use those indices to peek into the io.KeysDown[] array.
+    io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB;
+    io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
+    io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
+    io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
+    io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
+    io.KeyMap[ImGuiKey_PageUp] = GLFW_KEY_PAGE_UP;
+    io.KeyMap[ImGuiKey_PageDown] = GLFW_KEY_PAGE_DOWN;
+    io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
+    io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
+    io.KeyMap[ImGuiKey_Insert] = GLFW_KEY_INSERT;
+    io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
+    io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
+    io.KeyMap[ImGuiKey_Space] = GLFW_KEY_SPACE;
+    io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
+    io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
+    io.KeyMap[ImGuiKey_KeyPadEnter] = GLFW_KEY_KP_ENTER;
+    io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
+    io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
+    io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
+    io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
+    io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
+    io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;
+
+    io.SetClipboardTextFn = ImGui_ImplGlfw_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplGlfw_GetClipboardText;
+    io.ClipboardUserData = g_Window;
+#if defined(_WIN32)
+    io.ImeWindowHandle = (void*)glfwGetWin32Window(g_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.
+    // Missing cursors will return NULL and our _UpdateMouseCursor() function will use the Arrow cursor instead.)
+    GLFWerrorfun prev_error_callback = glfwSetErrorCallback(NULL);
+    g_MouseCursors[ImGuiMouseCursor_Arrow] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_TextInput] = glfwCreateStandardCursor(GLFW_IBEAM_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeNS] = glfwCreateStandardCursor(GLFW_VRESIZE_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeEW] = glfwCreateStandardCursor(GLFW_HRESIZE_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_Hand] = glfwCreateStandardCursor(GLFW_HAND_CURSOR);
+#if GLFW_HAS_NEW_CURSORS
+    g_MouseCursors[ImGuiMouseCursor_ResizeAll] = glfwCreateStandardCursor(GLFW_RESIZE_ALL_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeNESW] = glfwCreateStandardCursor(GLFW_RESIZE_NESW_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeNWSE] = glfwCreateStandardCursor(GLFW_RESIZE_NWSE_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_NotAllowed] = glfwCreateStandardCursor(GLFW_NOT_ALLOWED_CURSOR);
+#else
+    g_MouseCursors[ImGuiMouseCursor_ResizeAll] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeNESW] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_ResizeNWSE] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+    g_MouseCursors[ImGuiMouseCursor_NotAllowed] = glfwCreateStandardCursor(GLFW_ARROW_CURSOR);
+#endif
+    glfwSetErrorCallback(prev_error_callback);
+
+    // Chain GLFW callbacks: our callbacks will call the user's previously installed callbacks, if any.
+    g_PrevUserCallbackMousebutton = NULL;
+    g_PrevUserCallbackScroll = NULL;
+    g_PrevUserCallbackKey = NULL;
+    g_PrevUserCallbackChar = NULL;
+    if (install_callbacks)
+    {
+        g_InstalledCallbacks = true;
+        g_PrevUserCallbackMousebutton = glfwSetMouseButtonCallback(window, ImGui_ImplGlfw_MouseButtonCallback);
+        g_PrevUserCallbackScroll = glfwSetScrollCallback(window, ImGui_ImplGlfw_ScrollCallback);
+        g_PrevUserCallbackKey = glfwSetKeyCallback(window, ImGui_ImplGlfw_KeyCallback);
+        g_PrevUserCallbackChar = glfwSetCharCallback(window, ImGui_ImplGlfw_CharCallback);
+    }
+
+    g_ClientApi = client_api;
+    return true;
+}
+
+bool ImGui_ImplGlfw_InitForOpenGL(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_OpenGL);
+}
+
+bool ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_Vulkan);
+}
+
+bool ImGui_ImplGlfw_InitForOther(GLFWwindow* window, bool install_callbacks)
+{
+    return ImGui_ImplGlfw_Init(window, install_callbacks, GlfwClientApi_Unknown);
+}
+
+void ImGui_ImplGlfw_Shutdown()
+{
+    if (g_InstalledCallbacks)
+    {
+        glfwSetMouseButtonCallback(g_Window, g_PrevUserCallbackMousebutton);
+        glfwSetScrollCallback(g_Window, g_PrevUserCallbackScroll);
+        glfwSetKeyCallback(g_Window, g_PrevUserCallbackKey);
+        glfwSetCharCallback(g_Window, g_PrevUserCallbackChar);
+        g_InstalledCallbacks = false;
+    }
+
+    for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
+    {
+        glfwDestroyCursor(g_MouseCursors[cursor_n]);
+        g_MouseCursors[cursor_n] = NULL;
+    }
+    g_ClientApi = GlfwClientApi_Unknown;
+}
+
+static void ImGui_ImplGlfw_UpdateMousePosAndButtons()
+{
+    // Update buttons
+    ImGuiIO& io = ImGui::GetIO();
+    for (int i = 0; i < IM_ARRAYSIZE(io.MouseDown); i++)
+    {
+        // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
+        io.MouseDown[i] = g_MouseJustPressed[i] || glfwGetMouseButton(g_Window, i) != 0;
+        g_MouseJustPressed[i] = false;
+    }
+
+    // Update mouse position
+    const ImVec2 mouse_pos_backup = io.MousePos;
+    io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
+#ifdef __EMSCRIPTEN__
+    const bool focused = true; // Emscripten
+#else
+    const bool focused = glfwGetWindowAttrib(g_Window, GLFW_FOCUSED) != 0;
+#endif
+    if (focused)
+    {
+        if (io.WantSetMousePos)
+        {
+            glfwSetCursorPos(g_Window, (double)mouse_pos_backup.x, (double)mouse_pos_backup.y);
+        }
+        else
+        {
+            double mouse_x, mouse_y;
+            glfwGetCursorPos(g_Window, &mouse_x, &mouse_y);
+            io.MousePos = ImVec2((float)mouse_x, (float)mouse_y);
+        }
+    }
+}
+
+static void ImGui_ImplGlfw_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange) || glfwGetInputMode(g_Window, GLFW_CURSOR) == GLFW_CURSOR_DISABLED)
+        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(g_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(g_Window, g_MouseCursors[imgui_cursor] ? g_MouseCursors[imgui_cursor] : g_MouseCursors[ImGuiMouseCursor_Arrow]);
+        glfwSetInputMode(g_Window, GLFW_CURSOR, GLFW_CURSOR_NORMAL);
+    }
+}
+
+static void ImGui_ImplGlfw_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    memset(io.NavInputs, 0, sizeof(io.NavInputs));
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0)
+        return;
+
+    // Update gamepad inputs
+    #define MAP_BUTTON(NAV_NO, BUTTON_NO)       { if (buttons_count > BUTTON_NO && buttons[BUTTON_NO] == GLFW_PRESS) io.NavInputs[NAV_NO] = 1.0f; }
+    #define MAP_ANALOG(NAV_NO, AXIS_NO, V0, V1) { float v = (axes_count > AXIS_NO) ? axes[AXIS_NO] : V0; v = (v - V0) / (V1 - V0); if (v > 1.0f) v = 1.0f; if (io.NavInputs[NAV_NO] < v) io.NavInputs[NAV_NO] = v; }
+    int axes_count = 0, buttons_count = 0;
+    const float* axes = glfwGetJoystickAxes(GLFW_JOYSTICK_1, &axes_count);
+    const unsigned char* buttons = glfwGetJoystickButtons(GLFW_JOYSTICK_1, &buttons_count);
+    MAP_BUTTON(ImGuiNavInput_Activate,   0);     // Cross / A
+    MAP_BUTTON(ImGuiNavInput_Cancel,     1);     // Circle / B
+    MAP_BUTTON(ImGuiNavInput_Menu,       2);     // Square / X
+    MAP_BUTTON(ImGuiNavInput_Input,      3);     // Triangle / Y
+    MAP_BUTTON(ImGuiNavInput_DpadLeft,   13);    // D-Pad Left
+    MAP_BUTTON(ImGuiNavInput_DpadRight,  11);    // D-Pad Right
+    MAP_BUTTON(ImGuiNavInput_DpadUp,     10);    // D-Pad Up
+    MAP_BUTTON(ImGuiNavInput_DpadDown,   12);    // D-Pad Down
+    MAP_BUTTON(ImGuiNavInput_FocusPrev,  4);     // L1 / LB
+    MAP_BUTTON(ImGuiNavInput_FocusNext,  5);     // R1 / RB
+    MAP_BUTTON(ImGuiNavInput_TweakSlow,  4);     // L1 / LB
+    MAP_BUTTON(ImGuiNavInput_TweakFast,  5);     // R1 / RB
+    MAP_ANALOG(ImGuiNavInput_LStickLeft, 0,  -0.3f,  -0.9f);
+    MAP_ANALOG(ImGuiNavInput_LStickRight,0,  +0.3f,  +0.9f);
+    MAP_ANALOG(ImGuiNavInput_LStickUp,   1,  +0.3f,  +0.9f);
+    MAP_ANALOG(ImGuiNavInput_LStickDown, 1,  -0.3f,  -0.9f);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+    if (axes_count > 0 && buttons_count > 0)
+        io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+    else
+        io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+}
+
+void ImGui_ImplGlfw_NewFrame()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.Fonts->IsBuilt() && "Font atlas not built! It is generally built by the renderer backend. Missing call to renderer _NewFrame() function? e.g. ImGui_ImplOpenGL3_NewFrame().");
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    int display_w, display_h;
+    glfwGetWindowSize(g_Window, &w, &h);
+    glfwGetFramebufferSize(g_Window, &display_w, &display_h);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+    if (w > 0 && h > 0)
+        io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
+
+    // Setup time step
+    double current_time = glfwGetTime();
+    io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
+    g_Time = current_time;
+
+    ImGui_ImplGlfw_UpdateMousePosAndButtons();
+    ImGui_ImplGlfw_UpdateMouseCursor();
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplGlfw_UpdateGamepads();
+}