Draw order on Garmin devices


Obviously, the various Garmin devices use different ways to draw their maps.

I am familiar with the etrex series. I have a Vista HCx and I know that on the etrex devices and in Mapsource, areas are drawn by style file priority and other features are drawn in physical order. My hiking map uses this to show composite hiking marks made up from multiple layers.

The oregon and colorado draw differently and the icon composition does not work. It seems to always show the base icon. Some people have tried the result of test maps, but we have been unable to figure out what is happening on these devices. I am mostly interested in the POI drawing order. After the experiments, we have established that

  • it is not in physical or inverse physical order
  • it is not drawn by id or inverse id

Has anybody figured out something about the drawing order on these devices and how to influence it?


Regarding to pois I try to use poi groups that are not used by standard garmin symbols, like 0x1100 or 0x2800
Disadvantage is that those pois don’t show up in one of the poi categories.

Regarding to lines its just a matter of trial and error, some ways shows up fine in Mapsource and some GPS units, while on other units the display is crap.
Feel free to have a look at my maps and scripts on my website.

Cheers, Minko