Function ImGuiPlatformIO_Set_Renderer_SetWindowSize_PointerParam 

pub unsafe fn ImGuiPlatformIO_Set_Renderer_SetWindowSize_PointerParam(
    platform_io: *mut ImGuiPlatformIO,
    user_callback: Option<unsafe extern "C" fn(vp: *mut ImGuiViewport, size: *const ImVec2)>,
)

Install a C-compatible pointer-parameter callback for ImGuiPlatformIO::Renderer_SetWindowSize.

Safety

platform_io must be null or point to a live ImGuiPlatformIO. user_callback, when present, must obey Dear ImGui’s renderer callback contract and must not unwind.