Longer street names do not render

[mvglasow (2)]

Currently a lot of street names do not render on Navit, even when the street seems long enough to fit a label into. This seems to be more of an issue on high-resolution displays (e.g. Android HDPI) with a theme scaled appropriately (e.g. the 0606.at theme).

It appears that the current algorithm with which Navit renders labels on ways, such as street names, works in a manner similar to this:

• Break the way into segments from one point to the next
• Determine if the segment is long enough to render the label
• If yes, render the label.

This has drawbacks, which become apparent when a road is mapped with a hogh level of detail (i.e. high density of points):

• Short names (e.g. A2) get rendered very frequently – when this road is part of the route, the text almost completely obscures the colored line marking the route. (Style-dependent, of course.)
• Long names do not get rendered at all.

As a suggestion for improvement, I would suggest a label placing algorithm similar to the one in Mapnik:

• Place labels along paths (possibly with a limit on the maximum angle between two adjacent letters)
• Try to render each way label at least once
• Repeat labels on long ways (but with a reasonable amount of space in between)

This will probably be more resource-intensive than the current solution, but at the moment, the vast majority of street names is not rendering – not an acceptable solution.