Tom replies
The dynamics of cloth and other flexible fabrics can be deceptively difficult to master. It’s often tempting to delegate the task of communicating the presence of a cape or scarf to a series of amorphous, flowing lines. In some situations this can be expressive, but it rarely reflects the properties of real materials.
The important thing to remember is that the cape, just like the superhero figure, is a three-dimensional, physical object. It has weight and mass – it reflects light and casts shadows – just like other objects. The only thing that betrays its flexibility is movement and it’s relationships with other objects and forces. Otherwise, it might just as easily be moulded from clay or carved from stone.
Because this isn’t an animation exercise, I’ll rule out any actual movement (although I’ll do my best to suggest it a little in the static image), which leaves us with relationships. The arrows in the main picture represent the relationships that define the contours of the cape. Primarily, it’s being pulled between two rigid objects: the superhero (yellow) pulling one way, and the antenna (green) the other. Between the antenna and the figure, the cape is pulled quite flat, with a little sag to suggest that the figure has slowed down or stopped to check what’s happened. However, the antenna has broken the influence of the hero’s momentum, so everything to the left of it falls, tent-like, to the force of gravity (the red arrow).
Observing these basic principles enables me to create a cape that looks relatively realistic, despite a colourful, comic-book style.