strange mkgmap behaviour, lines-only style

laufkaefer · 2010-09-22T08:14:03.000Z

i’m trying to create a lines-only map with mkgmap (vers 1625).

background: i want car and bicycle routing on my etrex. so the idea is to have a background map containing the polygons, non-routing lines and pois, and 2 transparent maps with invisible roads for routing that i can switch between. so far so good, the principle seems to work.

now the problem: after inserting a couple of lines in the style mkgmap started turning out empty img files (empty means 0 bytes, not empty maps). after a couple of hours of trail and error it seems that mkgmap needs a certain amount of pois in the range of 0x100 to 0x900 (cities) to create working maps.

the 0-byte maps appear only if (1) --route is used and (2) both {name} and [road_speed/road_class] for the routable lines is set by the style

java’s memory usage is not the problem -loads of pois make the problem go away.

any ideas how to solve that?

greets, micha

csdf · 2010-09-22T09:12:09.000Z

My routing layer style* has no POIs and compiles fine.

http://www.cferrero.net/maps/map_downloads.html

laufkaefer · 2010-09-22T13:34:45.000Z

csdf:

My routing layer style* has no POIs and compiles fine.

http://www.cferrero.net/maps/map_downloads.html

your lines file works fine for me too, because it’s not naming the lines. as soon as i use { name ‘something’ } mkgmap hangs up.

csdf · 2010-09-22T15:09:56.000Z

Hm, I don’t have access to mkgmap so I can’t verify what you’re saying, but I’m curious as to why you’re naming the ways in the routing layer rather than naming them in the non-routing layer?

PS This is worth emailing the mkgmap-dev mailing list about, as it sounds like it could be a genuine bug.

Seldom · 2010-09-22T20:56:47.000Z

I’ve never made a routable map with different layers, but if you want to have the GPSr display “Right Turn Onto Main Street” doesn’t “Main” Street have to be the name of the way on the routable layer?

csdf · 2010-09-23T06:11:24.000Z

On my particular GPS and mkgmap layer setup*, I get suitable directions even without assigning names to the ways in the routing layer. This implies that the GPS is using the way names from the non-routing layer, but the routing information from the routing layer.

I’ll have to look at this more closely to figure out what’s going on.

lowest layer is routing layer with no way names, middle layer is OSM layer, opaque, with way names, top layer is transparent contour layer

laufkaefer · 2010-09-23T09:28:26.000Z

“Right Turn Onto Main Street” is exactly what i’m trying to achieve, but i wanna add the ref to the name too. i haven’t checked yet if the gps is able to pull names from the non-routing layer. i actually doubt it, because i have (invisible) bus and tram lines along the roads, and their names never turn up while routing.

But back to the problem: i found a way around it. using

name=* { set name=‘${name} (${ref})’ }

as 1st line of the lines file works. this names a lot of lines i don’t actually need, but much better than having a lot of pois i don’t want

@csdf: does your routing layer really have no way names? mkgmap automaticly uses the name tag, the {name} in the lines file is only needed if you wanna rewrite the name (like i do - adding the ref)

csdf · 2010-09-23T10:21:35.000Z

Ah, yes, you might be right there.

This does sound like a bug so I’d urge you to report it to the dev list so that it can be fixed for all.