
Geometry : 
Subject: [ggl] Polygon DP simplification
From: Barend Gehrels (barend)
Date: 20111007 09:41:43
Hi,
On 3092011 19:56, V D wrote:
> Hi,
>
> I'm trying to supply my own strategy to work around the problem for now.
> Using the same code as before, except now I'm trying:
>
>
> 27 typedef boost::geometry::strategy::distance::pythagoras<point_xy,
> point_xy, double> dist_strat;
> 28 typedef
> boost::geometry::strategy::simplify::douglas_peucker<point_xy,
> dist_strat > simp_strat;
> 30 simp_strat my_simplify_strat_test;
> 31 boost::geometry::simplify(original_1, simplified_1, 1.0 / 2048.0,
> my_simplify_strat_test);
>
>
> But I cannot get the strategy to compile, I get a pretty nasty compile
> error :
The Douglas Peucker strategy expects a pointtosegment distance
strategy. I'm happy to say that this is documented ;)
<http://www.boost.org/doc/libs/1_47_0/libs/geometry/doc/html/geometry/reference/strategies/strategy_simplify_douglas_peucker.html>
So the next lines will compile:
typedef boost::geometry::strategy::distance::pythagoras<point_xy,
point_xy, double> dist_strat;
typedef
boost::geometry::strategy::distance::projected_point<point_xy, point_xy,
double, dist_strat> pp_dist_strat;
typedef
boost::geometry::strategy::simplify::douglas_peucker<point_xy,
pp_dist_strat> simp_strat;
simp_strat my_simplify_strat_test;
// etc
However, this change would not have solved the problem, because the now
commented line would have taken the accompagnying comparable strategy
instead...
Regards, Barend
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