[mkgmap-dev] [PATCH v1] Handling of boundary multipolygons

Mon Apr 19 21:38:01 BST 2010


On 19.04.2010 21:08, WanMil wrote:
>>
>> I don't really understand what this patch is trying to achieve. There is
>> a patch by Thilo Hanneman (I'm attaching it for you) that makes it
>> possible to directly render relations from the relations file, I think
>> that is more useful - or don't I understand something here that you
>> intend to achieve???
>>
>
> Felix,
> I had a closer look at the patch and got some questions.
>
> As far as I understand the patch it tries to connect all ways of a 
> relation and tags these ways with a special mkgmap:gtype tag which is 
> a summary of all attributes of the relation(?)
>
> The convertRelation method tries to connect all ways of a relation. 
> The responsible addWayToListAndChainIfPossible method seems to care 
> about oneway tags if a way is classified as road.
> I don't know if the handling of two connected ways in following order 
> is correct:
> Way 1: road, oneway=yes
> Way 2: no road
> You will get one way tagged with oneway=yes although the 2nd way is no 
> road.
>
> All new assembled ways are put to the waymap, but with a different id. 
> The assembled way copies the original way id from the first way but 
> for the way map a fake id is generated. Although it's working I think 
> that's no good programming style.
>
> I am a bit surprised because I think that the patch creates at least 
> one new way for each relation. Doesn't that mean that you have n 
> overlapping ways in case you have n relations on the same way? 
> Probably I don't understand it so could you please explain what 
> happens if one way is contained in multiple relations?
>
>
> WanMil
>
>
It's Thilo Hannemann who wrote this patch. I just tried it and like the 
behaviour better than your patch and thought this patch could solve the 
same problem your patch is addressing. I have no deep enough 
understanding of the code to understand whether or not the patch is well 
written.