[Tagging] Relation for saying "x is attached to y"?

Tom Chance tom at acrewoods.net
Tue Aug 31 09:30:20 BST 2010

On 30 August 2010 14:18, Richard Welty <rwelty at averillpark.net> wrote:

>  On 8/30/10 9:06 AM, M∡rtin Koppenhoefer wrote:
>> +1, but site-relations might still be useful in the context of power
>> generators. There are situations where the single objects do not
>> overlap but are side a side, for example you might have 3 generators
>> with 3 chimneys and want to model which chimney is connected to which
>> generator.
> i'd lean towards site relations being useful because i think that
> the computational complexity of doing lots of polygon intersections
> is being underestimated. yes, for small bounding boxes it's ok,
> but consider if you needed to do it on a larger scale, it'd make
> certain tasks completely unreasonable (i'm not sure what those
> tasks might be yet, haven't thought about it.)

Based on this discussion, it seems that the best advice to put on my
proposal for power generators is:

- use site relations where the power=generator objects don't obviously
overlap with the buildings they relate to, particularly where you are
dealing with a cluster of nearby objects

- for simple cases like a wind turbine on a roof, it is helpful but not
necessary to use a site relation to specify the relationship between the
generator and the building


http://tom.acrewoods.net   http://twitter.com/tom_chance
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