Backends: SDL3: avoid calling SDL_SetTextInputArea() again if already installed the same text input area

[morrazzzz]

This will help to avoid situations where the same text input area is set. But we set it over and over again, generating the appropriate events, which may have its cost.

[ocornut]

Unlike #8727 i am not sure this is needed, as we already perform a check in the calling code:

    // Notify Platform/OS when our Input Method Editor cursor has moved (e.g. CJK inputs using Microsoft IME)
    ImGuiPlatformImeData* ime_data = &g.PlatformImeData;
    if (g.PlatformIO.Platform_SetImeDataFn != NULL && memcmp(ime_data, &g.PlatformImeDataPrev, sizeof(ImGuiPlatformImeData)) != 0)
    {
        IMGUI_DEBUG_LOG_IO("[io] Calling Platform_SetImeDataFn(): WantVisible: %d, InputPos (%.2f,%.2f)\n", ime_data->WantVisible, ime_data->InputPos.x, ime_data->InputPos.y);
        IM_ASSERT(ime_data->ViewportId == IMGUI_VIEWPORT_DEFAULT_ID); // master branch
        ImGuiViewport* viewport = GetMainViewport();
        g.PlatformIO.Platform_SetImeDataFn(&g, viewport, ime_data);
    }

[morrazzzz]

Unlike #8727 i am not sure this is needed, as we already perform a check in the calling code:

    // Notify Platform/OS when our Input Method Editor cursor has moved (e.g. CJK inputs using Microsoft IME)
    ImGuiPlatformImeData* ime_data = &g.PlatformImeData;
    if (g.PlatformIO.Platform_SetImeDataFn != NULL && memcmp(ime_data, &g.PlatformImeDataPrev, sizeof(ImGuiPlatformImeData)) != 0)
    {
        IMGUI_DEBUG_LOG_IO("[io] Calling Platform_SetImeDataFn(): WantVisible: %d, InputPos (%.2f,%.2f)\n", ime_data->WantVisible, ime_data->InputPos.x, ime_data->InputPos.y);
        IM_ASSERT(ime_data->ViewportId == IMGUI_VIEWPORT_DEFAULT_ID); // master branch
        ImGuiViewport* viewport = GetMainViewport();
        g.PlatformIO.Platform_SetImeDataFn(&g, viewport, ime_data);
    }

And how does this relate to the specified text input area? I recently watched this, it seems to be asking anyway, even without looking at this code.

[ocornut]

And how does this relate to the specified text input area?

The ImGuiPlatformImeData struct contains the text input position and height, so this is called whenever it changes.