[mkgmap-dev] draw-priority and layers

Sun Aug 30 08:07:59 BST 2009

Hi,

I'm trying to build a map with different layers, but I guess something
is wrong with the draw-priority parameter or the way i use it.

4 layers :

- Layer 1 : Contour line.
            draw-priority=25 (the highest).
            Transparent
            Specific style (contour) - the style is just (actually):
            natural=coastline [0x15 resolution 12]
            I generate a gmapsupp.img file

- Layer 2 : Personal data
            draw-priority=20 (a little less than layer 1).
            Transparent
            Specific style (perso)
            I generate a gmapsupp.img file

- Layer 3 : Normal OSM map.
            draw-priority=10 (the highest).
            NO Transparency (of course)
            Specific style (perso)
            I generate a gmapsupp.img file

- Layer 4 : Search map (with the road-name-pois parameter).
            draw-priority=1 (the lowest).
            No specific style.
            I generate a gmapsupp.img file

So I should have :

layer 1 (contour) : - - - - - - - - - - - - - - - - - - -
layer 2 (personal : - - - - - - - - - - - - - - - - - - -
layer 3 (normal)  : -------------------------------------
layer 4 (search)  : -------------------------------------

So, layers 1, 2 and 3 should be visible, not layer 4 as below a non
transparent layer.

Now, when I mix all those gmapsupp files (I rename all of them of
course) plus the two .TYP files (PERSO and CONTOUR), I have different
results depending the way I place them on the command line.

1) ex: mkgmap gmapsupp_layer1 gmapsupp_layer2 gmapsupp_layer3
gmapsupp_layer4 CONTOUR.TYP PERSO.TYP

makes layer2 not visible. The map displayed seems to use a default style.

2) ex: mkgmap gmapsupp_layer4 gmapsupp_layer2 gmapsupp_layer1
gmapsupp_layer4 CONTOUR.TYP PERSO.TYP

makes layer1 not visible. I don't know which style it uses, none of mine
at least.

3) Now if I compile layer1 with my "perso" style and if I remove the
CONTOUR.TYP file from the gmapsupp generated at the end of the process,
my perso style is again not used, and I have always one of the layers,
not displayed.

Maybe I do something wrong here, but I do not understand from the tests
I made and results I have how the draw-priority works. Francois

P.S. I tried all possible orders, but I never got a good result.
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