articulation of form
Articulation refers to the manner in which the surfaces of a form come together to define its shape and volume. An articulated form clearly reveals the edges of its surfaces and the corners at which they meet. Its surfaces appear as planes with distinct shapes; their overall configuration is legible and easily perceived. Similarly, an articulated group of forms accentuates the joints between its constituent forms to visually express their individuality. A form and its surface planes can be articulated by: differentiating adjacent surfaces with a change in material, color, texture, or pattern; developing the corner as a distinct linear element independent of the surfaces; removing the corner to physically separate adjacent planes; and lighting the form to create sharp distinctions of light and dark at its corners. (Ching, 1979)