Geometry Boost List: [ggl] Problems with the difference between two polygons

Subject: [ggl] Problems with the difference between two polygons
From: Enrico Leoni (lions.forever)
Date: 2011-07-28 22:25:42

Hi Barend,

On Tue, Jul 26, 2011 at 11:04 PM, Barend Gehrels <barend_at_[hidden]> wrote:
> I'm not yet experienced in using C++ in .NET, so I have to get used to this
> code style.

I have almost no serious experience with C++ so my code doesn't help for sure.

> Aren't you afraid that you are measuring a lot of copying? I see
> 2 calls to FromRegionToGglRegion, a call to FromGglRegionToRegion, within
> those calls I see nested calls, etc. Well, I see that for all those
> libraries, and it will be a minor part, but still...

Taking the third test, this is the time spent passing the poligons to
the libraries (ms):

Gtl - 8
Ggl - 9
KBool - 487
Gpc - 4
Clipper - 64

For Ggl the incidence is less than 1% but for KBool and Clipper the
incidence is greater (14% and 37%) because they are doing "something"
while a polygon is passed to them. So I think that the time spent
passing the poligons to the libraries has to be considered (also
keeping in mind that those libraries are wrapped to be used from
withing "managed" code).

> I will study it more. It is interesting to see this in a .NET environment.

In the end it is only a wrapper, C++/Cli is used to a minimum.

Regards, Enrico