Method CloseButton

include/imgui/imgui_widgets.cpp:903–938

Button to close a window

// Button to close a window
bool ImGui::CloseButton(ImGuiID id, const ImVec2& pos)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // Tweak 1: Shrink hit-testing area if button covers an abnormally large proportion of the visible region. That's in order to facilitate moving the window away. (#3825)
    // This may better be applied as a general hit-rect reduction mechanism for all widgets to ensure the area to move window is always accessible?
    const ImRect bb(pos, pos + ImVec2(g.FontSize, g.FontSize));
    ImRect bb_interact = bb;
    const float area_to_visible_ratio = window->OuterRectClipped.GetArea() / bb.GetArea();
    if (area_to_visible_ratio < 1.5f)
        bb_interact.Expand(ImTrunc(bb_interact.GetSize() * -0.25f));

    // Tweak 2: We intentionally allow interaction when clipped so that a mechanical Alt,Right,Activate sequence can always close a window.
    // (this isn't the common behavior of buttons, but it doesn't affect the user because navigation tends to keep items visible in scrolling layer).
    bool is_clipped = !ItemAdd(bb_interact, id);

    bool hovered, held;
    bool pressed = ButtonBehavior(bb_interact, id, &hovered, &held);
    if (is_clipped)
        return pressed;

    // Render
    ImU32 bg_col = GetColorU32(held ? ImGuiCol_ButtonActive : ImGuiCol_ButtonHovered);
    if (hovered)
        window->DrawList->AddRectFilled(bb.Min, bb.Max, bg_col);
    RenderNavCursor(bb, id, ImGuiNavRenderCursorFlags_Compact);
    const ImU32 cross_col = GetColorU32(ImGuiCol_Text);
    const ImVec2 cross_center = bb.GetCenter() - ImVec2(0.5f, 0.5f);
    const float cross_extent = g.FontSize * 0.5f * 0.7071f - 1.0f;
    const float cross_thickness = 1.0f * (float)(int)g.Style._MainScale; // FIXME-DPI
    window->DrawList->AddLine(cross_center + ImVec2(+cross_extent, +cross_extent), cross_center + ImVec2(-cross_extent, -cross_extent), cross_col, cross_thickness);
    window->DrawList->AddLine(cross_center + ImVec2(+cross_extent, -cross_extent), cross_center + ImVec2(-cross_extent, +cross_extent), cross_col, cross_thickness);

    return pressed;
}

bool ImGui::CollapseButton(ImGuiID id, const ImVec2& pos)
{