zgui/libs/imgui/backends/imgui_impl_sdl2.h

// 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.)

// 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

#pragma once
#include "imgui.h"      // IMGUI_IMPL_API
#ifndef IMGUI_DISABLE

struct SDL_Window;
struct SDL_Renderer;
struct _SDL_GameController;
typedef union SDL_Event SDL_Event;

// FIX(paoda)
extern "C" {
    // Follow "Getting Started" link and check examples/ folder to learn about using backends!
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForVulkan(SDL_Window* window);
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForD3D(SDL_Window* window);
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForMetal(SDL_Window* window);
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer);
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOther(SDL_Window* window);
    IMGUI_IMPL_API void     ImGui_ImplSDL2_Shutdown();
    IMGUI_IMPL_API void     ImGui_ImplSDL2_NewFrame();
    IMGUI_IMPL_API bool     ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event);
}

// Gamepad selection automatically starts in AutoFirst mode, picking first available SDL_Gamepad. You may override this.
// When using manual mode, caller is responsible for opening/closing gamepad.
enum ImGui_ImplSDL2_GamepadMode { ImGui_ImplSDL2_GamepadMode_AutoFirst, ImGui_ImplSDL2_GamepadMode_AutoAll, ImGui_ImplSDL2_GamepadMode_Manual };
// FIX(padoa)
extern "C" IMGUI_IMPL_API void     ImGui_ImplSDL2_SetGamepadMode(ImGui_ImplSDL2_GamepadMode mode, struct _SDL_GameController** manual_gamepads_array = NULL, int manual_gamepads_count = -1);

#endif // #ifndef IMGUI_DISABLE