[FOSS-GPS] FoxtrotGPS paint-optimize branch

[Sander van Grieken]

On Friday 14 May 2010 01:15:39 John Stowers wrote:
> On Thu, 2010-05-13 at 14:21 +0200, Sander van Grieken wrote:
> > Hi All,
> > 
> > Before the clash with Marcus Bauer and the forking of FoxtrotGPS I had worked on 
improving 
> > the graphics routines. These improvements were coded against Tango 0.99.2 and were 
> > noticably faster on my freerunner, although some regressions were still present. My 
> > patches were never reviewed or merged, and instead Marcus implemented another (more 
crude 
> > IMO) caching mechanism and released 0.99.3, from which FoxtrotGPS was forked. So in 
the 
> > past weeks I have worked on rebasing my patches against the FoxtrotGPS code base.
> 
> Hi,
> 
> This is just a friendly reminder to invite you all to check out
> osm-gps-map [1]. The optimisations you describe and many others were
> implemented in osm-gps-map a while ago. In fact, the excellent
> performance of osm-gps-map is one of the main reasons it is used in many
> of the most popular mapping apps on maemo.

It sure looks very nice and I'd love to ditch my stuff and replace it with osm-gps-map, 
but there are some issues, AFAICS from the API;

- There seems to be no callback for download-progress-reporting (number of threads, queue 
depth). I'd hate to ditch the visual download feedback foxtrot currently has.
- There seems to be no way to add/manage tile repositories programmatically.
- I assume I can register event handlers on click events? Will it associate click events 
with (groups of) images added to the widget?
- Is there a way to control visibility of the overlays programmatically?
- why are draw_gps and clear_gps exposed to the public API? They look like paint 
primitives, while the rest of the rendered objects are handled in a 'managed' fashion. I 
would have expected something like 'enable_draw_gps(boolean)' and 'update_position' or 
something.
- functions for managing tracks, images and layers are not symmetric; tracks have no 
remove function, layers have no remove function, images have no replace function (which 
would be nice for e.g. highlighting)

From playing around a bit with gpxview on maemo, there seem to be some glitches with 
downloading tiles. Sometimes a whole zoom-level stays white, sometimes a scaled tile 
doesn't get updated with the tile from the correct zoom level.

grtz,
Sander