Move into version control

1 files changed, 674 insertions, 0 deletions

diff --git a/src/imgui/backends/imgui_impl_sdl2.cpp b/src/imgui/backends/imgui_impl_sdl2.cpp
new file mode 100644
index 0000000..9f950bb
--- /dev/null
+++ b/src/imgui/backends/imgui_impl_sdl2.cpp
@@ -0,0 +1,674 @@
+// dear imgui: Platform Backend for SDL2
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL2 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+// (Prefer SDL 2.0.5+ for full feature support.)
+
+// Implemented features:
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Basic IME support. App needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+
+// 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.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// CHANGELOG
+// (minor and older changes stripped away, please see git history for details)
+//  2023-10-05: Inputs: Added support for extra ImGuiKey values: F13 to F24 function keys, app back/forward keys.
+//  2023-04-06: Inputs: Avoid calling SDL_StartTextInput()/SDL_StopTextInput() as they don't only pertain to IME. It's unclear exactly what their relation is to IME. (#6306)
+//  2023-04-04: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_TouchScreen. (#2702)
+//  2023-02-23: Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. (#6189, #6114, #3644)
+//  2023-02-07: Implement IME handler (io.SetPlatformImeDataFn will call SDL_SetTextInputRect()/SDL_StartTextInput()).
+//  2023-02-07: *BREAKING CHANGE* Renamed this backend file from imgui_impl_sdl.cpp/.h to imgui_impl_sdl2.cpp/.h in prevision for the future release of SDL3.
+//  2023-02-02: Avoid calling SDL_SetCursor() when cursor has not changed, as the function is surprisingly costly on Mac with latest SDL (may be fixed in next SDL version).
+//  2023-02-02: Added support for SDL 2.0.18+ preciseX/preciseY mouse wheel data for smooth scrolling + Scaling X value on Emscripten (bug?). (#4019, #6096)
+//  2023-02-02: Removed SDL_MOUSEWHEEL value clamping, as values seem correct in latest Emscripten. (#4019)
+//  2023-02-01: Flipping SDL_MOUSEWHEEL 'wheel.x' value to match other backends and offer consistent horizontal scrolling direction. (#4019, #6096, #1463)
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2022-09-26: Inputs: Disable SDL 2.0.22 new "auto capture" (SDL_HINT_MOUSE_AUTO_CAPTURE) which prevents drag and drop across windows for multi-viewport support + don't capture when drag and dropping. (#5710)
+//  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
+//  2022-03-22: Inputs: Fix mouse position issues when dragging outside of boundaries. SDL_CaptureMouse() erroneously still gives out LEAVE events when hovering OS decorations.
+//  2022-03-22: Inputs: Added support for extra mouse buttons (SDL_BUTTON_X1/SDL_BUTTON_X2).
+//  2022-02-04: Added SDL_Renderer* parameter to ImGui_ImplSDL2_InitForSDLRenderer(), so we can use SDL_GetRendererOutputSize() instead of SDL_GL_GetDrawableSize() when bound to a SDL_Renderer.
+//  2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
+//  2021-01-20: Inputs: calling new io.AddKeyAnalogEvent() for gamepad support, instead of writing directly to io.NavInputs[].
+//  2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
+//  2022-01-17: Inputs: always update key mods next and before key event (not in NewFrame) to fix input queue with very low framerates.
+//  2022-01-12: Update mouse inputs using SDL_MOUSEMOTION/SDL_WINDOWEVENT_LEAVE + fallback to provide it when focused but not hovered/captured. More standard and will allow us to pass it to future input queue API.
+//  2022-01-12: Maintain our own copy of MouseButtonsDown mask instead of using ImGui::IsAnyMouseDown() which will be obsoleted.
+//  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
+//  2021-08-17: Calling io.AddFocusEvent() on SDL_WINDOWEVENT_FOCUS_GAINED/SDL_WINDOWEVENT_FOCUS_LOST.
+//  2021-07-29: Inputs: MousePos is correctly reported when the host platform window is hovered but not focused (using SDL_GetMouseFocus() + SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, requires SDL 2.0.5+)
+//  2021-06-29: *BREAKING CHANGE* Removed 'SDL_Window* window' parameter to ImGui_ImplSDL2_NewFrame() which was unnecessary.
+//  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
+//  2021-03-22: Rework global mouse pos availability check listing supported platforms explicitly, effectively fixing mouse access on Raspberry Pi. (#2837, #3950)
+//  2020-05-25: Misc: Report a zero display-size when window is minimized, to be consistent with other backends.
+//  2020-02-20: Inputs: Fixed mapping for ImGuiKey_KeyPadEnter (using SDL_SCANCODE_KP_ENTER instead of SDL_SCANCODE_RETURN2).
+//  2019-12-17: Inputs: On Wayland, use SDL_GetMouseState (because there is no global mouse state).
+//  2019-12-05: Inputs: Added support for ImGuiMouseCursor_NotAllowed mouse cursor.
+//  2019-07-21: Inputs: Added mapping for ImGuiKey_KeyPadEnter.
+//  2019-04-23: Inputs: Added support for SDL_GameController (if ImGuiConfigFlags_NavEnableGamepad is set by user application).
+//  2019-03-12: Misc: Preserve DisplayFramebufferScale when main window is minimized.
+//  2018-12-21: Inputs: Workaround for Android/iOS which don't seem to handle focus related calls.
+//  2018-11-30: Misc: Setting up io.BackendPlatformName so it can be displayed in the About Window.
+//  2018-11-14: Changed the signature of ImGui_ImplSDL2_ProcessEvent() to take a 'const SDL_Event*'.
+//  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_sdl.cpp/.h away from the old combined SDL2+OpenGL/Vulkan examples.
+//  2018-06-08: Misc: ImGui_ImplSDL2_InitForOpenGL() now takes a SDL_GLContext parameter.
+//  2018-05-09: Misc: Fixed clipboard paste memory leak (we didn't call SDL_FreeMemory on the data returned by SDL_GetClipboardText).
+//  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors flag + honor ImGuiConfigFlags_NoMouseCursorChange flag.
+//  2018-02-16: Inputs: Added support for mouse cursors, honoring ImGui::GetMouseCursor() value.
+//  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.
+//  2018-02-05: Misc: Using SDL_GetPerformanceCounter() instead of SDL_GetTicks() to be able to handle very high framerate (1000+ FPS).
+//  2018-02-05: Inputs: Keyboard mapping is using scancodes everywhere instead of a confusing mixture of keycodes and scancodes.
+//  2018-01-20: Inputs: Added Horizontal Mouse Wheel support.
+//  2018-01-19: Inputs: When available (SDL 2.0.4+) using SDL_CaptureMouse() to retrieve coordinates outside of client area when dragging. Otherwise (SDL 2.0.3 and before) testing for SDL_WINDOW_INPUT_FOCUS instead of SDL_WINDOW_MOUSE_FOCUS.
+//  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"
+#ifndef IMGUI_DISABLE
+#include "imgui_impl_sdl2.h"
+
+// Clang warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wimplicit-int-float-conversion"  // warning: implicit conversion from 'xxx' to 'float' may lose precision
+#endif
+
+// SDL
+#include <SDL.h>
+#include <SDL_syswm.h>
+#if defined(__APPLE__)
+#include <TargetConditionals.h>
+#endif
+
+#if SDL_VERSION_ATLEAST(2,0,4) && !defined(__EMSCRIPTEN__) && !defined(__ANDROID__) && !(defined(__APPLE__) && TARGET_OS_IOS) && !defined(__amigaos4__)
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    1
+#else
+#define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    0
+#endif
+#define SDL_HAS_VULKAN                      SDL_VERSION_ATLEAST(2,0,6)
+
+// SDL Data
+struct ImGui_ImplSDL2_Data
+{
+    SDL_Window*     Window;
+    SDL_Renderer*   Renderer;
+    Uint64          Time;
+    Uint32          MouseWindowID;
+    int             MouseButtonsDown;
+    SDL_Cursor*     MouseCursors[ImGuiMouseCursor_COUNT];
+    SDL_Cursor*     LastMouseCursor;
+    int             PendingMouseLeaveFrame;
+    char*           ClipboardTextData;
+    bool            MouseCanUseGlobalState;
+
+    ImGui_ImplSDL2_Data()   { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendPlatformUserData 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.
+// FIXME: multi-context support is not well tested and probably dysfunctional in this backend.
+// FIXME: some shared resources (mouse cursor shape, gamepad) are mishandled when using multi-context.
+static ImGui_ImplSDL2_Data* ImGui_ImplSDL2_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDL2_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
+}
+
+// Functions
+static const char* ImGui_ImplSDL2_GetClipboardText(void*)
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    bd->ClipboardTextData = SDL_GetClipboardText();
+    return bd->ClipboardTextData;
+}
+
+static void ImGui_ImplSDL2_SetClipboardText(void*, const char* text)
+{
+    SDL_SetClipboardText(text);
+}
+
+// Note: native IME will only display if user calls SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1") _before_ SDL_CreateWindow().
+static void ImGui_ImplSDL2_SetPlatformImeData(ImGuiViewport*, ImGuiPlatformImeData* data)
+{
+    if (data->WantVisible)
+    {
+        SDL_Rect r;
+        r.x = (int)data->InputPos.x;
+        r.y = (int)data->InputPos.y;
+        r.w = 1;
+        r.h = (int)data->InputLineHeight;
+        SDL_SetTextInputRect(&r);
+    }
+}
+
+static ImGuiKey ImGui_ImplSDL2_KeycodeToImGuiKey(int keycode)
+{
+    switch (keycode)
+    {
+        case SDLK_TAB: return ImGuiKey_Tab;
+        case SDLK_LEFT: return ImGuiKey_LeftArrow;
+        case SDLK_RIGHT: return ImGuiKey_RightArrow;
+        case SDLK_UP: return ImGuiKey_UpArrow;
+        case SDLK_DOWN: return ImGuiKey_DownArrow;
+        case SDLK_PAGEUP: return ImGuiKey_PageUp;
+        case SDLK_PAGEDOWN: return ImGuiKey_PageDown;
+        case SDLK_HOME: return ImGuiKey_Home;
+        case SDLK_END: return ImGuiKey_End;
+        case SDLK_INSERT: return ImGuiKey_Insert;
+        case SDLK_DELETE: return ImGuiKey_Delete;
+        case SDLK_BACKSPACE: return ImGuiKey_Backspace;
+        case SDLK_SPACE: return ImGuiKey_Space;
+        case SDLK_RETURN: return ImGuiKey_Enter;
+        case SDLK_ESCAPE: return ImGuiKey_Escape;
+        case SDLK_QUOTE: return ImGuiKey_Apostrophe;
+        case SDLK_COMMA: return ImGuiKey_Comma;
+        case SDLK_MINUS: return ImGuiKey_Minus;
+        case SDLK_PERIOD: return ImGuiKey_Period;
+        case SDLK_SLASH: return ImGuiKey_Slash;
+        case SDLK_SEMICOLON: return ImGuiKey_Semicolon;
+        case SDLK_EQUALS: return ImGuiKey_Equal;
+        case SDLK_LEFTBRACKET: return ImGuiKey_LeftBracket;
+        case SDLK_BACKSLASH: return ImGuiKey_Backslash;
+        case SDLK_RIGHTBRACKET: return ImGuiKey_RightBracket;
+        case SDLK_BACKQUOTE: return ImGuiKey_GraveAccent;
+        case SDLK_CAPSLOCK: return ImGuiKey_CapsLock;
+        case SDLK_SCROLLLOCK: return ImGuiKey_ScrollLock;
+        case SDLK_NUMLOCKCLEAR: return ImGuiKey_NumLock;
+        case SDLK_PRINTSCREEN: return ImGuiKey_PrintScreen;
+        case SDLK_PAUSE: return ImGuiKey_Pause;
+        case SDLK_KP_0: return ImGuiKey_Keypad0;
+        case SDLK_KP_1: return ImGuiKey_Keypad1;
+        case SDLK_KP_2: return ImGuiKey_Keypad2;
+        case SDLK_KP_3: return ImGuiKey_Keypad3;
+        case SDLK_KP_4: return ImGuiKey_Keypad4;
+        case SDLK_KP_5: return ImGuiKey_Keypad5;
+        case SDLK_KP_6: return ImGuiKey_Keypad6;
+        case SDLK_KP_7: return ImGuiKey_Keypad7;
+        case SDLK_KP_8: return ImGuiKey_Keypad8;
+        case SDLK_KP_9: return ImGuiKey_Keypad9;
+        case SDLK_KP_PERIOD: return ImGuiKey_KeypadDecimal;
+        case SDLK_KP_DIVIDE: return ImGuiKey_KeypadDivide;
+        case SDLK_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case SDLK_KP_MINUS: return ImGuiKey_KeypadSubtract;
+        case SDLK_KP_PLUS: return ImGuiKey_KeypadAdd;
+        case SDLK_KP_ENTER: return ImGuiKey_KeypadEnter;
+        case SDLK_KP_EQUALS: return ImGuiKey_KeypadEqual;
+        case SDLK_LCTRL: return ImGuiKey_LeftCtrl;
+        case SDLK_LSHIFT: return ImGuiKey_LeftShift;
+        case SDLK_LALT: return ImGuiKey_LeftAlt;
+        case SDLK_LGUI: return ImGuiKey_LeftSuper;
+        case SDLK_RCTRL: return ImGuiKey_RightCtrl;
+        case SDLK_RSHIFT: return ImGuiKey_RightShift;
+        case SDLK_RALT: return ImGuiKey_RightAlt;
+        case SDLK_RGUI: return ImGuiKey_RightSuper;
+        case SDLK_APPLICATION: return ImGuiKey_Menu;
+        case SDLK_0: return ImGuiKey_0;
+        case SDLK_1: return ImGuiKey_1;
+        case SDLK_2: return ImGuiKey_2;
+        case SDLK_3: return ImGuiKey_3;
+        case SDLK_4: return ImGuiKey_4;
+        case SDLK_5: return ImGuiKey_5;
+        case SDLK_6: return ImGuiKey_6;
+        case SDLK_7: return ImGuiKey_7;
+        case SDLK_8: return ImGuiKey_8;
+        case SDLK_9: return ImGuiKey_9;
+        case SDLK_a: return ImGuiKey_A;
+        case SDLK_b: return ImGuiKey_B;
+        case SDLK_c: return ImGuiKey_C;
+        case SDLK_d: return ImGuiKey_D;
+        case SDLK_e: return ImGuiKey_E;
+        case SDLK_f: return ImGuiKey_F;
+        case SDLK_g: return ImGuiKey_G;
+        case SDLK_h: return ImGuiKey_H;
+        case SDLK_i: return ImGuiKey_I;
+        case SDLK_j: return ImGuiKey_J;
+        case SDLK_k: return ImGuiKey_K;
+        case SDLK_l: return ImGuiKey_L;
+        case SDLK_m: return ImGuiKey_M;
+        case SDLK_n: return ImGuiKey_N;
+        case SDLK_o: return ImGuiKey_O;
+        case SDLK_p: return ImGuiKey_P;
+        case SDLK_q: return ImGuiKey_Q;
+        case SDLK_r: return ImGuiKey_R;
+        case SDLK_s: return ImGuiKey_S;
+        case SDLK_t: return ImGuiKey_T;
+        case SDLK_u: return ImGuiKey_U;
+        case SDLK_v: return ImGuiKey_V;
+        case SDLK_w: return ImGuiKey_W;
+        case SDLK_x: return ImGuiKey_X;
+        case SDLK_y: return ImGuiKey_Y;
+        case SDLK_z: return ImGuiKey_Z;
+        case SDLK_F1: return ImGuiKey_F1;
+        case SDLK_F2: return ImGuiKey_F2;
+        case SDLK_F3: return ImGuiKey_F3;
+        case SDLK_F4: return ImGuiKey_F4;
+        case SDLK_F5: return ImGuiKey_F5;
+        case SDLK_F6: return ImGuiKey_F6;
+        case SDLK_F7: return ImGuiKey_F7;
+        case SDLK_F8: return ImGuiKey_F8;
+        case SDLK_F9: return ImGuiKey_F9;
+        case SDLK_F10: return ImGuiKey_F10;
+        case SDLK_F11: return ImGuiKey_F11;
+        case SDLK_F12: return ImGuiKey_F12;
+        case SDLK_F13: return ImGuiKey_F13;
+        case SDLK_F14: return ImGuiKey_F14;
+        case SDLK_F15: return ImGuiKey_F15;
+        case SDLK_F16: return ImGuiKey_F16;
+        case SDLK_F17: return ImGuiKey_F17;
+        case SDLK_F18: return ImGuiKey_F18;
+        case SDLK_F19: return ImGuiKey_F19;
+        case SDLK_F20: return ImGuiKey_F20;
+        case SDLK_F21: return ImGuiKey_F21;
+        case SDLK_F22: return ImGuiKey_F22;
+        case SDLK_F23: return ImGuiKey_F23;
+        case SDLK_F24: return ImGuiKey_F24;
+        case SDLK_AC_BACK: return ImGuiKey_AppBack;
+        case SDLK_AC_FORWARD: return ImGuiKey_AppForward;
+    }
+    return ImGuiKey_None;
+}
+
+static void ImGui_ImplSDL2_UpdateKeyModifiers(SDL_Keymod sdl_key_mods)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.AddKeyEvent(ImGuiMod_Ctrl, (sdl_key_mods & KMOD_CTRL) != 0);
+    io.AddKeyEvent(ImGuiMod_Shift, (sdl_key_mods & KMOD_SHIFT) != 0);
+    io.AddKeyEvent(ImGuiMod_Alt, (sdl_key_mods & KMOD_ALT) != 0);
+    io.AddKeyEvent(ImGuiMod_Super, (sdl_key_mods & KMOD_GUI) != 0);
+}
+
+// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
+bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+
+    switch (event->type)
+    {
+        case SDL_MOUSEMOTION:
+        {
+            ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            io.AddMouseSourceEvent(event->motion.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
+            return true;
+        }
+        case SDL_MOUSEWHEEL:
+        {
+            //IMGUI_DEBUG_LOG("wheel %.2f %.2f, precise %.2f %.2f\n", (float)event->wheel.x, (float)event->wheel.y, event->wheel.preciseX, event->wheel.preciseY);
+#if SDL_VERSION_ATLEAST(2,0,18) // If this fails to compile on Emscripten: update to latest Emscripten!
+            float wheel_x = -event->wheel.preciseX;
+            float wheel_y = event->wheel.preciseY;
+#else
+            float wheel_x = -(float)event->wheel.x;
+            float wheel_y = (float)event->wheel.y;
+#endif
+#ifdef __EMSCRIPTEN__
+            wheel_x /= 100.0f;
+#endif
+            io.AddMouseSourceEvent(event->wheel.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseWheelEvent(wheel_x, wheel_y);
+            return true;
+        }
+        case SDL_MOUSEBUTTONDOWN:
+        case SDL_MOUSEBUTTONUP:
+        {
+            int mouse_button = -1;
+            if (event->button.button == SDL_BUTTON_LEFT) { mouse_button = 0; }
+            if (event->button.button == SDL_BUTTON_RIGHT) { mouse_button = 1; }
+            if (event->button.button == SDL_BUTTON_MIDDLE) { mouse_button = 2; }
+            if (event->button.button == SDL_BUTTON_X1) { mouse_button = 3; }
+            if (event->button.button == SDL_BUTTON_X2) { mouse_button = 4; }
+            if (mouse_button == -1)
+                break;
+            io.AddMouseSourceEvent(event->button.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
+            io.AddMouseButtonEvent(mouse_button, (event->type == SDL_MOUSEBUTTONDOWN));
+            bd->MouseButtonsDown = (event->type == SDL_MOUSEBUTTONDOWN) ? (bd->MouseButtonsDown | (1 << mouse_button)) : (bd->MouseButtonsDown & ~(1 << mouse_button));
+            return true;
+        }
+        case SDL_TEXTINPUT:
+        {
+            io.AddInputCharactersUTF8(event->text.text);
+            return true;
+        }
+        case SDL_KEYDOWN:
+        case SDL_KEYUP:
+        {
+            ImGui_ImplSDL2_UpdateKeyModifiers((SDL_Keymod)event->key.keysym.mod);
+            ImGuiKey key = ImGui_ImplSDL2_KeycodeToImGuiKey(event->key.keysym.sym);
+            io.AddKeyEvent(key, (event->type == SDL_KEYDOWN));
+            io.SetKeyEventNativeData(key, event->key.keysym.sym, event->key.keysym.scancode, event->key.keysym.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
+            return true;
+        }
+        case SDL_WINDOWEVENT:
+        {
+            // - When capturing mouse, SDL will send a bunch of conflicting LEAVE/ENTER event on every mouse move, but the final ENTER tends to be right.
+            // - However we won't get a correct LEAVE event for a captured window.
+            // - In some cases, when detaching a window from main viewport SDL may send SDL_WINDOWEVENT_ENTER one frame too late,
+            //   causing SDL_WINDOWEVENT_LEAVE on previous frame to interrupt drag operation by clear mouse position. This is why
+            //   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)
+                io.AddFocusEvent(true);
+            else if (event->window.event == SDL_WINDOWEVENT_FOCUS_LOST)
+                io.AddFocusEvent(false);
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
+
+    // Check and store if we are on a SDL backend that supports global mouse position
+    // ("wayland" and "rpi" don't support it, but we chose to use a white-list instead of a black-list)
+    bool mouse_can_use_global_state = false;
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+    const char* sdl_backend = SDL_GetCurrentVideoDriver();
+    const char* global_mouse_whitelist[] = { "windows", "cocoa", "x11", "DIVE", "VMAN" };
+    for (int n = 0; n < IM_ARRAYSIZE(global_mouse_whitelist); n++)
+        if (strncmp(sdl_backend, global_mouse_whitelist[n], strlen(global_mouse_whitelist[n])) == 0)
+            mouse_can_use_global_state = true;
+#endif
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDL2_Data* bd = IM_NEW(ImGui_ImplSDL2_Data)();
+    io.BackendPlatformUserData = (void*)bd;
+    io.BackendPlatformName = "imgui_impl_sdl2";
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;       // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;        // We can honor io.WantSetMousePos requests (optional, rarely used)
+
+    bd->Window = window;
+    bd->Renderer = renderer;
+    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
+
+    io.SetClipboardTextFn = ImGui_ImplSDL2_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplSDL2_GetClipboardText;
+    io.ClipboardUserData = nullptr;
+    io.SetPlatformImeDataFn = ImGui_ImplSDL2_SetPlatformImeData;
+
+    // Load mouse cursors
+    bd->MouseCursors[ImGuiMouseCursor_Arrow] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_ARROW);
+    bd->MouseCursors[ImGuiMouseCursor_TextInput] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_IBEAM);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeAll] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEALL);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNS] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENS);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeEW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZEWE);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNESW] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENESW);
+    bd->MouseCursors[ImGuiMouseCursor_ResizeNWSE] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_SIZENWSE);
+    bd->MouseCursors[ImGuiMouseCursor_Hand] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_HAND);
+    bd->MouseCursors[ImGuiMouseCursor_NotAllowed] = SDL_CreateSystemCursor(SDL_SYSTEM_CURSOR_NO);
+
+    // Set platform dependent data in viewport
+    // 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))
+    {
+#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.
+    // (This is unfortunately a global SDL setting, so enabling it might have a side-effect on your application.
+    // It is unlikely to make a difference, but if your app absolutely needs to ignore the initial on-focus click:
+    // you can ignore SDL_MOUSEBUTTONDOWN events coming right after a SDL_WINDOWEVENT_FOCUS_GAINED)
+#ifdef SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH
+    SDL_SetHint(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, "1");
+#endif
+
+    // From 2.0.18: Enable native IME.
+    // IMPORTANT: This is used at the time of SDL_CreateWindow() so this will only affects secondary windows, if any.
+    // For the main window to be affected, your application needs to call this manually before calling SDL_CreateWindow().
+#ifdef SDL_HINT_IME_SHOW_UI
+    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
+#endif
+
+    // From 2.0.22: Disable auto-capture, this is preventing drag and drop across multiple windows (see #5710)
+#ifdef SDL_HINT_MOUSE_AUTO_CAPTURE
+    SDL_SetHint(SDL_HINT_MOUSE_AUTO_CAPTURE, "0");
+#endif
+
+    return true;
+}
+
+bool ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
+{
+    IM_UNUSED(sdl_gl_context); // Viewport branch will need this.
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForVulkan(SDL_Window* window)
+{
+#if !SDL_HAS_VULKAN
+    IM_ASSERT(0 && "Unsupported");
+#endif
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForD3D(SDL_Window* window)
+{
+#if !defined(_WIN32)
+    IM_ASSERT(0 && "Unsupported");
+#endif
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForMetal(SDL_Window* window)
+{
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+bool ImGui_ImplSDL2_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer)
+{
+    return ImGui_ImplSDL2_Init(window, renderer);
+}
+
+bool ImGui_ImplSDL2_InitForOther(SDL_Window* window)
+{
+    return ImGui_ImplSDL2_Init(window, nullptr);
+}
+
+void ImGui_ImplSDL2_Shutdown()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    if (bd->ClipboardTextData)
+        SDL_free(bd->ClipboardTextData);
+    for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
+        SDL_FreeCursor(bd->MouseCursors[cursor_n]);
+    bd->LastMouseCursor = nullptr;
+
+    io.BackendPlatformName = nullptr;
+    io.BackendPlatformUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDL2_UpdateMouseData()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    ImGuiIO& io = ImGui::GetIO();
+
+    // 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) ? SDL_TRUE : SDL_FALSE);
+    SDL_Window* focused_window = SDL_GetKeyboardFocus();
+    const bool is_app_focused = (bd->Window == focused_window);
+#else
+    const bool is_app_focused = (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0; // SDL 2.0.3 and non-windowed systems: single-viewport only
+#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)
+            SDL_WarpMouseInWindow(bd->Window, (int)io.MousePos.x, (int)io.MousePos.y);
+
+        // (Optional) Fallback to provide mouse position when focused (SDL_MOUSEMOTION already provides this when hovered or captured)
+        if (bd->MouseCanUseGlobalState && bd->MouseButtonsDown == 0)
+        {
+            int window_x, window_y, mouse_x_global, mouse_y_global;
+            SDL_GetGlobalMouseState(&mouse_x_global, &mouse_y_global);
+            SDL_GetWindowPosition(bd->Window, &window_x, &window_y);
+            io.AddMousePosEvent((float)(mouse_x_global - window_x), (float)(mouse_y_global - window_y));
+        }
+    }
+}
+
+static void ImGui_ImplSDL2_UpdateMouseCursor()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
+        return;
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+
+    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
+    if (io.MouseDrawCursor || imgui_cursor == ImGuiMouseCursor_None)
+    {
+        // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
+        SDL_ShowCursor(SDL_FALSE);
+    }
+    else
+    {
+        // Show OS mouse cursor
+        SDL_Cursor* expected_cursor = bd->MouseCursors[imgui_cursor] ? bd->MouseCursors[imgui_cursor] : bd->MouseCursors[ImGuiMouseCursor_Arrow];
+        if (bd->LastMouseCursor != expected_cursor)
+        {
+            SDL_SetCursor(expected_cursor); // SDL function doesn't have an early out (see #6113)
+            bd->LastMouseCursor = expected_cursor;
+        }
+        SDL_ShowCursor(SDL_TRUE);
+    }
+}
+
+static void ImGui_ImplSDL2_UpdateGamepads()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
+        return;
+
+    // Get gamepad
+    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
+    SDL_GameController* game_controller = SDL_GameControllerOpen(0);
+    if (!game_controller)
+        return;
+    io.BackendFlags |= ImGuiBackendFlags_HasGamepad;
+
+    // Update gamepad inputs
+    #define IM_SATURATE(V)                      (V < 0.0f ? 0.0f : V > 1.0f ? 1.0f : V)
+    #define MAP_BUTTON(KEY_NO, BUTTON_NO)       { io.AddKeyEvent(KEY_NO, SDL_GameControllerGetButton(game_controller, BUTTON_NO) != 0); }
+    #define MAP_ANALOG(KEY_NO, AXIS_NO, V0, V1) { float vn = (float)(SDL_GameControllerGetAxis(game_controller, AXIS_NO) - V0) / (float)(V1 - V0); vn = IM_SATURATE(vn); io.AddKeyAnalogEvent(KEY_NO, vn > 0.1f, vn); }
+    const int thumb_dead_zone = 8000;           // SDL_gamecontroller.h suggests using this value.
+    MAP_BUTTON(ImGuiKey_GamepadStart,           SDL_CONTROLLER_BUTTON_START);
+    MAP_BUTTON(ImGuiKey_GamepadBack,            SDL_CONTROLLER_BUTTON_BACK);
+    MAP_BUTTON(ImGuiKey_GamepadFaceLeft,        SDL_CONTROLLER_BUTTON_X);              // Xbox X, PS Square
+    MAP_BUTTON(ImGuiKey_GamepadFaceRight,       SDL_CONTROLLER_BUTTON_B);              // Xbox B, PS Circle
+    MAP_BUTTON(ImGuiKey_GamepadFaceUp,          SDL_CONTROLLER_BUTTON_Y);              // Xbox Y, PS Triangle
+    MAP_BUTTON(ImGuiKey_GamepadFaceDown,        SDL_CONTROLLER_BUTTON_A);              // Xbox A, PS Cross
+    MAP_BUTTON(ImGuiKey_GamepadDpadLeft,        SDL_CONTROLLER_BUTTON_DPAD_LEFT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadRight,       SDL_CONTROLLER_BUTTON_DPAD_RIGHT);
+    MAP_BUTTON(ImGuiKey_GamepadDpadUp,          SDL_CONTROLLER_BUTTON_DPAD_UP);
+    MAP_BUTTON(ImGuiKey_GamepadDpadDown,        SDL_CONTROLLER_BUTTON_DPAD_DOWN);
+    MAP_BUTTON(ImGuiKey_GamepadL1,              SDL_CONTROLLER_BUTTON_LEFTSHOULDER);
+    MAP_BUTTON(ImGuiKey_GamepadR1,              SDL_CONTROLLER_BUTTON_RIGHTSHOULDER);
+    MAP_ANALOG(ImGuiKey_GamepadL2,              SDL_CONTROLLER_AXIS_TRIGGERLEFT,  0.0f, 32767);
+    MAP_ANALOG(ImGuiKey_GamepadR2,              SDL_CONTROLLER_AXIS_TRIGGERRIGHT, 0.0f, 32767);
+    MAP_BUTTON(ImGuiKey_GamepadL3,              SDL_CONTROLLER_BUTTON_LEFTSTICK);
+    MAP_BUTTON(ImGuiKey_GamepadR3,              SDL_CONTROLLER_BUTTON_RIGHTSTICK);
+    MAP_ANALOG(ImGuiKey_GamepadLStickLeft,      SDL_CONTROLLER_AXIS_LEFTX,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickRight,     SDL_CONTROLLER_AXIS_LEFTX,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadLStickUp,        SDL_CONTROLLER_AXIS_LEFTY,  -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadLStickDown,      SDL_CONTROLLER_AXIS_LEFTY,  +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickLeft,      SDL_CONTROLLER_AXIS_RIGHTX, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickRight,     SDL_CONTROLLER_AXIS_RIGHTX, +thumb_dead_zone, +32767);
+    MAP_ANALOG(ImGuiKey_GamepadRStickUp,        SDL_CONTROLLER_AXIS_RIGHTY, -thumb_dead_zone, -32768);
+    MAP_ANALOG(ImGuiKey_GamepadRStickDown,      SDL_CONTROLLER_AXIS_RIGHTY, +thumb_dead_zone, +32767);
+    #undef MAP_BUTTON
+    #undef MAP_ANALOG
+}
+
+void ImGui_ImplSDL2_NewFrame()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDL2_Init()?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+    int display_w, display_h;
+    SDL_GetWindowSize(bd->Window, &w, &h);
+    if (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_MINIMIZED)
+        w = h = 0;
+    if (bd->Renderer != nullptr)
+        SDL_GetRendererOutputSize(bd->Renderer, &display_w, &display_h);
+    else
+        SDL_GL_GetDrawableSize(bd->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 (we don't use SDL_GetTicks() because it is using millisecond resolution)
+    // (Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. Happens in VMs and Emscripten, see #6189, #6114, #3644)
+    static Uint64 frequency = SDL_GetPerformanceFrequency();
+    Uint64 current_time = SDL_GetPerformanceCounter();
+    if (current_time <= bd->Time)
+        current_time = bd->Time + 1;
+    io.DeltaTime = bd->Time > 0 ? (float)((double)(current_time - bd->Time) / frequency) : (float)(1.0f / 60.0f);
+    bd->Time = current_time;
+
+    if (bd->PendingMouseLeaveFrame && bd->PendingMouseLeaveFrame >= ImGui::GetFrameCount() && bd->MouseButtonsDown == 0)
+    {
+        bd->MouseWindowID = 0;
+        bd->PendingMouseLeaveFrame = 0;
+        io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+    }
+
+    ImGui_ImplSDL2_UpdateMouseData();
+    ImGui_ImplSDL2_UpdateMouseCursor();
+
+    // Update game controllers (if enabled and available)
+    ImGui_ImplSDL2_UpdateGamepads();
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
+
+#endif // #ifndef IMGUI_DISABLE