The recipe covers how to use ClutterBindConstraint
to bind actor sizes together.
It gives some examples of where this approach is appropriate,
as well as explaining an alternative using allocation-changed
or notify::* signals.
Three examples are given:
1. Resizing a texture to the stage.
2. Resizing a rectangle to act as a transparent overlay on
top of a texture (using constraints).
3. Resizing a rectangle to act as a transparent overlay on
top of a texture, but with a size proportional to the texture
(using a handler connected to allocation-changed signals
emitted by the texture).
