Planes are flat surface areas which depict contours of the face in a flat manner. The technique of breaking down objects into simpler forms is at least 500 years old, and is still used all the time by 3d animators today.
In the popular digital sculpting program ZBrush you can create virtual sculptures, and in this video tutorial you can see how the artist looked at each plane of the face as a starting point to model an entire face.
In the following illustration we can see how Loomis simplified the face into flat planes.
And here we can see how Paolo Uccello did so with a vase drawing he made nearly 500 years ago.
Planes of the face can have simple variations in value which can distinguish where a plane ends, and another begins.
And planes can help simplify cartoon characters making it easy to draw from multiple angles. Such as in this step by step guide by Loomis on how to draw cartoons.
But why is this an important skill as it concerns 3d modeling? Well, for starters it isn’t that difficult to model an extremely complicated looking character in a program like ZBrush. However the more vertices present, the slower a character will perform in 3d. That’s why all 3d characters are simplified down to more efficient characters.
In the tutorial below we can see how simple objects are even simplified down to easier planar shapes in Blender. We are going to be doing the same, except with drawing.
For todays exercise we will be working from photos of animals and humans, and your task will be to redraw these images in a much simpler way. As always you are welcome to use a tablet to draw (not trace!) the images.
If you are looking for more inspiration, and are interested in using Blender I recommend starting with this set of tutorials. Blender is free to download and there are hundreds and hundreds of tutorials online which go from very basic to (as seen in the video below) quite advanced.