[postgis-users] Using a buffer with a LineString covering the whole world

[Paul Ramsey]

If he's just buffering one line, he should calculate it by hand, like
a Real Man :)

On Wed, Feb 11, 2009 at 10:22 AM, Chris Hermansen
<chris.hermansen at timberline.ca> wrote:
> It might not be that bad, Paul, depending on the latitude of the start
> and end points, which - USA <-> France - sounds like they might be
> pretty close.  If it was say Seattle Paris, that would be ok.
>
> Paul Ramsey wrote:
>> that's really not a good option. mercator does not preserve
>> length/distance, so the buffer would end up larger at one end than the
>> other, and furthermore would not be the expected width, since it would
>> be built far from the latitude of true scale.
>>
>> P.
>>
>> On Wed, Feb 11, 2009 at 8:52 AM, Pavel Iacovlev
>> <iacovlev.pavel at gmail.com> wrote:
>>
>>> As an option you can use google mercator projection for the whole world. But
>>> read carefully docs about it to understand the precision loss.
>>>
>>> http://genuchten.blogspot.com/2008/04/srid-stuff-in-postgis.html would be a
>>> good start.
>>>
>>> On Wed, Feb 11, 2009 at 6:26 PM, Matthes Rieke <matthes.rieke.01 at gmail.com>
>>> wrote:
>>>
>>>> Hi all,
>>>>
>>>> I am currently running into this problem: I have a LineString in lat/long
>>>> coordinates (SRID 4326 - going from USA to france). I now want to create a
>>>> buffer in meters from this. So the normal way to transfrom the coordinates
>>>> to a planar CRS, buffering, then transforming back to 4326 does not work
>>>> (the Line is covering many UTM zones). What would be a reasonable solution
>>>> for this problem?
>>>>
>>>> Thanks and regards,
>>>> Matthes
>>>>
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>>>
>>> --
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>
>
> --
> Regards,
>
> Chris Hermansen         mailto:chris.hermansen at timberline.ca
> tel+1.604.714.2878 · fax+1.604.733.0631 · mob+1.778.232.0644
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