[Dune] Fwd: Re: Returning Geometries As Objects

[Martin Nolte]

-------- Original Message --------
Subject: Re: [Dune] Returning Geometries As Objects
Date: Wed, 25 Jan 2012 13:19:59 +0100
From: Martin Nolte <nolte at mathematik.uni-freiburg.de>
To: Markus Blatt <markus at dr-blatt.de>

Hi Markus,

the decision is up to the grid developer. When returning a reference, the
entity / intersection must provide the storage for the implementation object
(as before).

Best,

Martin

On 01/25/2012 12:02 PM, Markus Blatt wrote:
> On Wed, Jan 25, 2012 at 11:04:36AM +0100, Jö Fahlke wrote:
>> Am Wed, 25. Jan 2012, 09:49:01 +0100 schrieb Martin Nolte:
>>> The changes try to be as uninvasive as possible. However, due to
>>> code evolution, there are some unnecessary changes left. The
>>> greatest benefit for a developer is the possibility to create a new
>>> geometry object whenever the geometry is requested. This gives us
>>> essentially two types of geometry implementations:
>>> (a) actually returned geometry implementations,
>>> (b) references to the actual geometry (as was previously enforced).
>>
>> So, in essence, Dune::Geometry may (a) store the actual geometry or may (b) be
>> a wrapper class holding a reference/pointer to the actual geometry?
>>
>> In case be (b), how long is a geometry object guaranteed to be valid?  Until
>> the entity/intersection object it was obtained from changes it's value or is
>> destroyed?
>>
>
> Who chooses between a and b? Does the user of the grid have the choice
> or does the grid developer decide whether a or b is available?
>
> Kind regards,
>
> Markus
>

-- 
Dr. Martin Nolte <nolte at mathematik.uni-freiburg.de>

Universität Freiburg                                   phone: +49-761-203-5630
Abteilung für angewandte Mathematik                    fax:   +49-761-203-5632
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79104 Freiburg, Germany