How to create line draworders in Basecamp

Forget about line draworders on your gps

There is no logic to the algorithm - ie bridges over dual carriageways or motorways often only overlap one of the highways . However, it is possible to force line draworders in Basecamp.

bitmap footbridge ALWAYS on top

One way to get 'overlapping' bridges is by placing them all in one img and make the priority of this map higher than the rst of the maps - in my experience, this is not guaranteed to work.

The following applies to Basecamp and more than likely will not apply to your gps device.

Bridges


Garmin TOPO No bridges across Motorways	Bridges Over Motorways

Routable types have a higher draworder then non routable ones
Changing a non routable line from a bitmap to a non bitmap gives it a higher draworder
Change rivers, streams etc to bitmap lines - In TYPWiz.click 'Convert to Bitmap' .
Some extended type numbers also have a default higher draworder , ie 108

The following procedure is just one way of creating bridges Problem: You can't use 0x1 for a Motorway as nothing crosses 0x1 ! Solution 1 Bridge No Outline:
Use 0x1 - 0x7 as bridges	highway=motorway & bridge=* [0x1 road_class=4 road_speed=7 resolution 24 continue]
use 0x12 for mways and make this line TRANSPARENT	highway=motorway [ 0x12 road_class=4 road_speed=7 resolution 16 continue]
use an extended line number to show the motorway AS A BITMAP	highway=motorway [ 0x10108 resolution 16 ]

Solution 2 Bridge With Outline:
Use 0x108 as a a transparent bridge outline	bridge=* [0x1 resolution 24 continue]
Use 0x1 - 0x7 as bridges	highway=motorway & bridge=* [0x2 road_class=4 road_speed=7 resolution 24 continue]
use 0x12 for mways and make this line TRANSPARENT	highway=motorway [ 0x12 road_class=4 road_speed=7 resolution 16 continue]
use an extended line to show the motorway AS A BITMAP	highway=motorway [ 0x10108 resolution 16 ]

Using this method you can have railway lines / even canals ALWAYS crossing motorways and other highways.For railway lines perhaps use type 0x0 (no bitmap)

The draw back is :

you will need to reorganise you highway numbers
You are having to create extra lines