Method UpdateKeyboardInputs

tutorials/common/imgui/imgui.cpp:4172–4280

}

static void ImGui::UpdateKeyboardInputs()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    // Import legacy keys or verify they are not used
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    if (io.BackendUsingLegacyKeyArrays == 0)
    {
        // Backend used new io.AddKeyEvent() API: Good! Verify that old arrays are never written to externally.
        for (int n = 0; n < ImGuiKey_LegacyNativeKey_END; n++)
            IM_ASSERT((io.KeysDown[n] == false || IsKeyDown((ImGuiKey)n)) && "Backend needs to either only use io.AddKeyEvent(), either only fill legacy io.KeysDown[] + io.KeyMap[]. Not both!");
    }
    else
    {
        if (g.FrameCount == 0)
            for (int n = ImGuiKey_LegacyNativeKey_BEGIN; n < ImGuiKey_LegacyNativeKey_END; n++)
                IM_ASSERT(g.IO.KeyMap[n] == -1 && "Backend is not allowed to write to io.KeyMap[0..511]!");

        // Build reverse KeyMap (Named -> Legacy)
        for (int n = ImGuiKey_NamedKey_BEGIN; n < ImGuiKey_NamedKey_END; n++)
            if (io.KeyMap[n] != -1)
            {
                IM_ASSERT(IsLegacyKey((ImGuiKey)io.KeyMap[n]));
                io.KeyMap[io.KeyMap[n]] = n;
            }

        // Import legacy keys into new ones
        for (int n = ImGuiKey_LegacyNativeKey_BEGIN; n < ImGuiKey_LegacyNativeKey_END; n++)
            if (io.KeysDown[n] || io.BackendUsingLegacyKeyArrays == 1)
            {
                const ImGuiKey key = (ImGuiKey)(io.KeyMap[n] != -1 ? io.KeyMap[n] : n);
                IM_ASSERT(io.KeyMap[n] == -1 || IsNamedKey(key));
                io.KeysData[key].Down = io.KeysDown[n];
                if (key != n)
                    io.KeysDown[key] = io.KeysDown[n]; // Allow legacy code using io.KeysDown[GetKeyIndex()] with old backends
                io.BackendUsingLegacyKeyArrays = 1;
            }
        if (io.BackendUsingLegacyKeyArrays == 1)
        {
            GetKeyData(ImGuiMod_Ctrl)->Down = io.KeyCtrl;
            GetKeyData(ImGuiMod_Shift)->Down = io.KeyShift;
            GetKeyData(ImGuiMod_Alt)->Down = io.KeyAlt;
            GetKeyData(ImGuiMod_Super)->Down = io.KeySuper;
        }
    }

#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    if (io.BackendUsingLegacyNavInputArray && nav_gamepad_active)
    {
        #define MAP_LEGACY_NAV_INPUT_TO_KEY1(_KEY, _NAV1)           do { io.KeysData[_KEY].Down = (io.NavInputs[_NAV1] > 0.0f); io.KeysData[_KEY].AnalogValue = io.NavInputs[_NAV1]; } while (0)
        #define MAP_LEGACY_NAV_INPUT_TO_KEY2(_KEY, _NAV1, _NAV2)    do { io.KeysData[_KEY].Down = (io.NavInputs[_NAV1] > 0.0f) || (io.NavInputs[_NAV2] > 0.0f); io.KeysData[_KEY].AnalogValue = ImMax(io.NavInputs[_NAV1], io.NavInputs[_NAV2]); } while (0)
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceDown, ImGuiNavInput_Activate);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceRight, ImGuiNavInput_Cancel);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceLeft, ImGuiNavInput_Menu);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceUp, ImGuiNavInput_Input);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadDpadLeft, ImGuiNavInput_DpadLeft);