Subject: Re: [geometry] [Boost-users] [boost.geometry] buffer distance strategies
From: Barend Gehrels (barend_at_[hidden])
Date: 2014-10-29 18:21:21
gchlebus wrote On 24-10-2014 16:44:
> I am wondering whether it would be possible to achieve anisotropic buffering
> (distances in neg x, pos x, neg y, pos y can have different values) of a
> polygon using the buffer function with custom-implemented distance strategy.
> What I want to achieve is presented on the figure 2-b in the following
> I would be grateful to hear from you whether it is doable, and if positive,
> how one could implement such a custom distance strategy.
The current distance strategy has (currently) no means to get the angle,
or a vector of the new point to be buffered. We can consider adding that.
However, by writing custom strategies for join, side, point (for
point-buffers) and possibly end (for line-buffers) you should be able to
create this, because these have this information.
Attached a program doing similar things with polygons and points (I vary
the distance based on angle - you will have to do something with your
The output is also attached.
The program defines three custom strategies, all based on the same
mechanism, to create interesting output.
I did not do the end-strategy but that would look similar, you can look
at the provided end-strategy (round) and apply the same function.
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