Function ImGui_RenderColorRectWithAlphaCheckerboard 

pub unsafe extern "C" fn ImGui_RenderColorRectWithAlphaCheckerboard(
    draw_list: *mut ImDrawList,
    p_min: ImVec2,
    p_max: ImVec2,
    fill_col: ImU32,
    grid_step: f32,
    grid_off: ImVec2,
    rounding: f32,
    flags: ImDrawFlags,
)