[mkgmap-dev] patch to improve style throughput

Wed Apr 25 22:28:45 BST 2018

Hi Gerd,

> thanks for review, I've added a unit test to show why your version doesn't work.

Yes, that doesn't work.

Well, I'll just say what I was trying to do.

With these rules:

	a=* {set b=2}
	b=1 [0x10404 resolution 24]

and an element with a=1, it is not possible to
match the b=1 rule, but it is still tried anyway.
In this case changeableTags contains the full b=2 keystring
so it ought to be possible to recognise that the
second rule cannot match.

..Steve

> I see no simple way to improve the index much more. I thought about a different approach:
> Instead of doing all the calculations before any rule is really executed we might do this dynamically.
> Each rule which changes or adds tags would point to a list of further rules which are to be checked. Only when such
> a change really happens the additional rules are checked.
> No idea if this can be implemented more efficiently than the current static index.