Re: [Libosmscout-development] ios Navigation

[Tim T. <ti...@fr...>]

Hello Dmitry,

> One more question - how can I configure the rendering of street  
> names. For example, draw from a certain zoom or change font  
> size. 

For rendering of the street names you can either define attributes for  
a WAY.TEXT (text follows way contour) or for a WAY.SHIELD (place on  
top of the way).

The used font name and size is defined as an attribute of the  
MapParameter that gets handed to the renderer. Currently only one font  
is supported (though you can define different font sizes in the style  
sheet). Font sizes in the style sheet are relative to the font size as  
given in the MapParameter. In principle more font should be possible,  
one must just make sure that the lookup between the style sheet entry  
and the actual font is O(1) or maximum (nlogn) to keep things fast.

See description in the standard.oss style sheet:
WAY.TEXT => "A text style for a path..."
WAY.SHIELD => "A shield style for a path has..."

Example:
  [MAG veryClose-] {
    [TYPE highway_tertiary,
          highway_unclassified,
          highway_road,
          highway_residential,
          highway_living_street,
          highway_service,
          highway_track,
          leisure_track] WAY.TEXT { label: name; size: 0.9; }
}

For the given way types in the magnification between veryClose-maximum  
zoom draw a label for these ways based on the way name using s  
slightly smaller font then default.

You can find a mapping between magnifcation level names and  
traditionaly zoom levels in Magnification.h:


     enum Mag {
       magWorld     =                        1, //  0
       magContinent =                       16, //  4
       magState     =                       32, //  5
       magStateOver =                       64, //  6
       magCounty    =                      128, //  7
       magRegion    =                      256, //  8
       magProximity =                      512, //  9
       magCityOver  =                     1024, // 10
       magCity      =                   2*1024, // 11
       magSuburb    =                 2*2*1024, // 12
       magDetail    =               2*2*2*1024, // 13
       magClose     =             2*2*2*2*1024, // 14
       magVeryClose =           2*2*2*2*2*1024, // 16
       magBlock     =         2*2*2*2*2*2*1024, // 18
       magStreet    =   2*2*2*2*2*2*2*2*2*1024, // 19
       magHouse     = 2*2*2*2*2*2*2*2*2*2*1024  // 20
     };

-- 
Gruß...
    Tim