Store profile precalculated data

[xivk]

For performance reasons we need to precalculate profile metrics. A profile is a function:

• { attributes-set } -> { factors and speeds }

We need to store this inline to remove the need to load attributes sets for each edge and translate them to factors and speeds again and again. We should also consider storing aspects to enable highly flexible profiles based on a set of precalculated fixed edge properties or 'aspects'.

A solution could be:

• { attribute-set } -> [ { aspect1, value1 }, { aspect2, value2 } ] -> { factors and speeds }

The aspect key value pairs are stored where appropriate.

[xivk]

When storing values on edges we need a way to retrieve them very fast. We probably need to distinguish between a few weight types:

• Exceptions: like cycling networks, they will apply to a tiny part of the network
• Covering: these aspects are on all edges, like 'access', 'comfort', 'speed'...

[xivk]

This is done now, what is left is to cache the length of an edge:

• [x] Cache the length of an edge.

This need for this was confirmed by performance testing: