[mkgmap-dev] Test cases for possible is-in-hook

Sat Jan 4 11:42:33 GMT 2020

Hi Jan

OK, but Outside needs to be expressed in the inverse, ie

e) any-in-or-on  >  3/ 4/ 5/ 6/

and then tested as ... is_in(tag,val,any-in-or-on)=false ...

because the logic will look for all correctly tagged polygons nearby
and then check each in turn to see if it matches the accuracy
requirements and stop with 'true' if it does, returning 'false' if none
match. So, if there were two matching areas, the line could be outside
one and inside the other, and 'outside' would return true.

The cases 1/ to 6/ would be more logically expressed with 3 flags:
  IN, ON, OUT
set as the algorithm examines the relationship of the line segments
with the polygon segments, then we have:

a) all-in            IN and not (ON or OUT)
   Jan's alternative IN and not OUT
b) all-in-or-on      (IN or ON) and not OUT 
c) all-on            ON and not (OUT or IN)
d) any-in            IN
e) any-in-or-on      IN or ON

Ticker

On Fri, 2020-01-03 at 23:49 +0100, jan meisters wrote:
> Hi all,
> 
> I would define the 6 cases in Tickers given (with the explained
> handling of apexes) as followed:
> 
> a) all-in			>	4/ 5/
> b) all-in-or-on		>	3/ 4/ 5/
> c) all-on			>	3/
> d) any-in			>	4/ 5/ 6/
> Outside			>	1/ 2/
> 
> These options are impressively complex, I can´t imagine any further
> yet.
> 
> Jan
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