Method RenderDimmedBackgroundBehindWindow

src/imgui/imgui.cpp:5734–5759

}

static void ImGui::RenderDimmedBackgroundBehindWindow(ImGuiWindow* window, ImU32 col)
{
    if ((col & IM_COL32_A_MASK) == 0)
        return;

    ImGuiViewportP* viewport = (ImGuiViewportP*)GetMainViewport();
    ImRect viewport_rect = viewport->GetMainRect();

    // Draw behind window by moving the draw command at the FRONT of the draw list
    {
        // We've already called AddWindowToDrawData() which called DrawList->ChannelsMerge() on DockNodeHost windows,
        // and draw list have been trimmed already, hence the explicit recreation of a draw command if missing.
        // FIXME: This is creating complication, might be simpler if we could inject a drawlist in drawdata at a given position and not attempt to manipulate ImDrawCmd order.
        ImDrawList* draw_list = window->RootWindow->DrawList;
        if (draw_list->CmdBuffer.Size == 0)
            draw_list->AddDrawCmd();
        draw_list->PushClipRect(viewport_rect.Min - ImVec2(1, 1), viewport_rect.Max + ImVec2(1, 1), false); // FIXME: Need to stricty ensure ImDrawCmd are not merged (ElemCount==6 checks below will verify that)
        draw_list->AddRectFilled(viewport_rect.Min, viewport_rect.Max, col);
        ImDrawCmd cmd = draw_list->CmdBuffer.back();
        IM_ASSERT(cmd.ElemCount == 6);
        draw_list->CmdBuffer.pop_back();
        draw_list->CmdBuffer.push_front(cmd);
        draw_list->AddDrawCmd(); // We need to create a command as CmdBuffer.back().IdxOffset won't be correct if we append to same command.
        draw_list->PopClipRect();
    }
}

ImGuiWindow* ImGui::FindBottomMostVisibleWindowWithinBeginStack(ImGuiWindow* parent_window)
{