FIGURE- Planes and Construction

Plane- a flat or level surface (no elevations or depressions WITHIN). An area of a two-dimensional surface having determinate extension and spatial direction or position.

Spatial direction and position are important terms for us to consider. This allows the eye to read if a plane is sloped toward or away, what angle , and what the profile of the shape is. Joining of multiple planes begins to create form or the impression of three dimensions. A simple example is to think of a diamond (the precious stone) it has a form that is composed of a multitude of planes or facets. Drawing the human body can be approached this way, thinking of the three big masses (head, rib cage, pelvis) as blocks with cubic limbs extending. Gradually more and more subtle planes can be added making more complex transitions and form. It is best to WORK FROM BIG TO SMALL- the whole to the detail, the big body masses to smaller masses, etc. The following examples are all from Bridgman's Complete Guide to Drawing From Life. These are also presented in an order of process , more or less. Remember basic to more complex.

The 3 Masses of the body (Head, Rib Cage, and Pelvis) note how they are consider blocks (and their proportions) and their stacked position. The twist and bend are easy to see and describe as the relationship of these blocks turn or lean. Essential for carrying the basic movement of the figure.
Horizontal Axis of shoulders, pelvis, knees. This gives an understanding of where the balance is, how the body manages to distribute its weight evenly, and where the body opens or compresses etc.
Basic example of planes going up the back and side (almost two sided at its simplest).What is important to notice is the forward and backward slope as it moves upward or downward.
This is a good way to think about each body part, as a cross section. Is its mass similar to a cylinder, box or pyramid- round, square, triangle.
Further example of this shape of mass. Notice how the shapes alternate as they transition through a limb.
This example of the arm is interesting to see how planes can rise up and dip down as they meet another mass. To use Bridgman's term, they wedge together and interlock.
Planes of the leg from behind, notice how the planes begin to describe muscles.
The torso is a complex structure with a multitude of planes describing its surface. these planes all change as the torso twists and bends. Again we see the muscle groups beginning to be described by planes.