What artists know that most architects haven’t yet fully embraced is the practice of drawing the dark shapes. It’s not natural when drafting on a computer to visualize exactly how the dark is going to move across the room especially when our entire focus tends to be on washing the space in the light.
I have recently revisited this lesson while gesture painting from a live model. All architects should practice figure drawing regularly if for no other reason; it will remind them to draw shadows as a solid shape. When all you have is 3 minutes to capture a form as with the drawing above, the dark and light shapes are just about all you get. What you learn is that there is no light until you have the dark defined and therefore no form. This is also true of architectural space.