window->RootNonPopupWindow=!(flags&(ImGuiWindowFlags_ChildWindow|ImGuiWindowFlags_Popup))||(flags&ImGuiWindowFlags_Modal) ? window:parent_window->RootNonPopupWindow;// Used to display TitleBgActive color and for selecting which window to use for NavWindowing
window->RootNonPopupWindow=!(flags&(ImGuiWindowFlags_ChildWindow|ImGuiWindowFlags_Popup))||(flags&ImGuiWindowFlags_Modal)||(parent_window==NULL)? window:parent_window->RootNonPopupWindow;// Used to display TitleBgActive color and for selecting which window to use for NavWindowing
// This is how we end up with child menus appearing (most-commonly) on the right of the parent menu.
IM_ASSERT(window_pos_set_by_api);
floathorizontal_overlap=style.ItemSpacing.x;// We want some overlap to convey the relative depth of each popup (currently the amount of overlap it is hard-coded to style.ItemSpacing.x, may need to introduce another style value).
ImGuiWindow*ParentWindow;// Immediate parent in the window stack *regardless* of whether this window is a child window or not)
ImGuiWindow*ParentWindow;// If we are a child window, this is pointing to our parent.
ImGuiWindow*RootWindow;// Generally point to ourself. If we are a child window, this is pointing to the first non-child parent window.
ImGuiWindow*RootNonPopupWindow;// Generally point to ourself. Used to display TitleBgActive color and for selecting which window to use for NavWindowing