[postgis-users] st_box2d

[JP de Miranda]

Mark,
I do believe that box2d returns a polygon with 5 points.
Here is an example
My starting polygon

POLYGON((-81.507568359375 42.7631458668949,-81.4141845703125 43.6023850422415,-81.32080078125 44.441624217588,-79.6893310546875 44.6526402614971,-78.057861328125 44.8636563054061,-77.047119140625 44.3015041922804,-76.036376953125 43.7393520791547,-76.7889404296875 43.0448886007946,-77.54150390625 42.3504251224346,-78.310546875 42.3260577253395,-79.07958984375 42.3016903282445,-80.2935791015625 42.5324180975697,-81.507568359375 42.7631458668949))


Results of box2d

POLYGON((-81.507568359375 42.3016891479492,-81.507568359375 44.8636589050293,-76.036376953125 44.8636589050293,-76.036376953125 42.3016891479492,-81.507568359375 42.3016891479492))




Mark Cave-Ayland wrote:
> JP de Miranda wrote:
>> Hi,
>> I'm trying to find out some information about the polygon returned by 
>> box2d.
>> Namely, what is the order of the points?  Are they always in the 
>> format POLYGON((minx miny, minx maxy, maxx maxy, maxx miny, minx miny))?
>>
>> I checked the postgis docs and it doesn't describe the returned polygon.
>> Thanks for your help.
>
>
> Hi JP,
>
> BOX2Ds are simply expressed as BOX2D(x1 y1, x2 y2) where x1, y1 is the 
> lower left corner and x2, y2 is upper right corner.
>
>
> HTH,
>
> Mark.
>

-- 
JP de Miranda
Supervisor, Web Services

First Base Solutions
www.firstbasesolutions.com
140 Renfrew Drive, Suite 100
Markham, Ontario, Canada
L3R 6B3
T: 905.477.3600 x302
F: 905.477.0892
jpdemiranda at firstbasesolutions.com