Hi,

Maybe Anita Graser has something on the topic? https://anitagraser.com/ She 
does a lot of work in visualization mass transportation. Yes, looking at line 
azimut by color was the way I did it in the past.  It’s still a good way when 
the network has a lot of snapping errors.  My algorithm with permit you find 
those problems. If you see a network problem my algorithm does not find, please 
tell me and I could work them in.

Nicolas Cadieux
https://gitlab.com/njacadieux

> Le 8 oct. 2021 à 02:54, Andreas Neumann <[email protected]> a écrit :
> 
> 
> Hi,
> 
> Besides on what was discussed here on the list already, I can add the 
> following information: the Swiss QGIS user group has mandated Nyall Dawson to 
> carry out a couple of days of research exactly on this topic - kind of a 
> feasibility study if it would be possible to draw such network maps "on the 
> fly" / automatically - with transit maps and hiking maps (multiple parallel 
> hiking routes) in mind.
> 
> I believe Nyall will work on this before the end of the year.
> 
> Of course we cannot promise anything - but based on the outcome of this 
> study, there might be follow-up work pending. If there is interest from other 
> users we might want to organize an institutional crowd funding initiative.
> 
> This won't help you immediately - but it might be good for you to know that 
> the problem is on the radar. If there is a positive outcome in the study, 
> there might be implementation work pending next year.
> 
> Greetings,
> 
> Andreas
> 
>> On 2021-10-07 23:53, David Strip wrote:
>> 
>> For a transit map, it seems the offset would not be constant. Consider two 
>> bus routes that overlap along a single street in their routes. On that 
>> street, the two lines typically would be offset to opposite sides of the 
>> line representing the street. On the rest of the route, however, the route 
>> would be shown as lying directly over the centerline, not offset to either 
>> side. Life gets even more complicated when multiple routes overlap with 
>> different numbers of other routes at various points on the map.  Or at least 
>> that's what I've typically seen on transit maps. 
>> 
>>> On 10/7/2021 3:30 PM, Nicolas Cadieux wrote:
>>> Hi,
>>> You can also trim the lines in the symbology (at least in QGIS 3.20) as 
>>> well as giving it an offset.  That will insure that intersection are not 
>>> overlapping in the offset.
>>> 
>>> Nicolas Cadieux
>>> https://gitlab.com/njacadieux
>>> 
>>>> Le 7 oct. 2021 à 17:23, Nicolas Cadieux <[email protected]> a 
>>>> écrit :
>>>> 
>>>> Oups!  Forgot the list...
>>>> 
>>>> Nicolas Cadieux
>>>> https://gitlab.com/njacadieux
>>>> 
>>>>> Le 7 oct. 2021 à 17:23, Nicolas Cadieux <[email protected]> a 
>>>>> écrit :
>>>>> 
>>>>> Hi,
>>>>> You can automatically draw an offset by adding a offset in the symbology. 
>>>>>  Things get more complicated when line vectorization changes directions 
>>>>> as the offset flips side depending on, for example, if the line is drawn 
>>>>> from A to B or B to A.  
>>>>>  
>>>>> In the QGIS models, https://plugins.qgis.org/, go to models then Fix 
>>>>> Directional Network models 1,2 and 3.  That will help you find problems 
>>>>> (like disconnected lines) but also identify all the lines that are 
>>>>> flipped. You can then flip them manually or figure out an algorithm to do 
>>>>> it automatically.
>>>>>  
>>>>> You will also find a boring YouTube video on my YouTube channel. 
>>>>> https://youtu.be/v61PafSByvM
>>>>> 
>>>>> Nicolas Cadieux
>>>>> https://gitlab.com/njacadieux
>>>>> 
>>>>>> Le 7 oct. 2021 à 14:17, Hugh Kelley <[email protected]> a écrit :
>>>>>> 
>>>>>> Hi all,
>>>>>>  
>>>>>> I'm wondering if anyone has any good tricks for mapping bus routes. The 
>>>>>> key problem is defining how to offset lines where the routes overlap.
>>>>>>  
>>>>>> I've handled this by chopping up the lines and offsetting in postgis 
>>>>>> according to some st_dwithins and st_intersections but wanted to see if 
>>>>>> there is anything in the wide world of QGIS that I'm not aware of.
>>>>>>  
>>>>>> My understanding is that it's a fairly significant challenge to do a 
>>>>>> great job with it. A company called transitapp had an interesting blog 
>>>>>> post about it a while ago. 
>>>>>> https://archive.transitapp.com/transit-maps-apple-vs-google-vs-us-cb3d7cd2c362#.e9kcryzg1
>>>>>> 
>>>>>> 
>>>>>> Hugh 
>>>>>>  
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