Variable interfacing

[aconstlink]

A major problem is how to properly and generically interface with variables in order to connect engine layers.

For UI purposes, the property system exists. For real-time the wire framework is used. But how can the engine interface with random variables in order to expose them as properties or as slots in a wire node.

So I try to implement a variable interfacing library that exposes more information about variables but still have them efficient enough to be used during run-time.

This can be used to connect to keyframe animations, other computations or a UI property sheet in a generic way.

[aconstlink]

I actually experimented with meta data and some stored setter/getter stuff. But it turned out that is sucked, so I changed my mind and moved everything to wire.

In wire, there will be a variable type which will exactly do what we need.

I.e. connecting to variables/subvariables through slots. So there will be no unsafe pointer bingbang. It then will also nicely integrate into the concurrent node framework.