
Most of them have a bunch of variables listed, but in our examples we will
only use a few. The rest of the variables are assumed to have default values.
In the OpenSCAD manual, you might see more than we even list since func-
tionality gets added to the program all the time.
Default, in this case, means that the program says, “unless you tell me oth-
erwise, I’m assuming that all the other variables have certain predefined
values.” For example, most OpenSCAD shapes have a variable called
ce n te r, which is defaulted to false. The meaning varies a bit depending on
the shape (see the OpenSCAD manual), but for example center = false
for a cyl