Create a simple 3-D model of a two-story house, a detached garage, and a three-story apartment building next door. Use shadow casting to model the shadow line at 8:00 a.m., 10:00 a.m., noon, 2:00 p.m., and 5:00 p.m. You can either estimate or consult specialized charts used by architects to locate the sun at these times of day.