Improve rendering on e-ink devices

[pshunter]

Hi, I have an e-ink tablet and since the screen can only display black and white (and grey shades) I tried every map style available.
It seems that it's not possible to use distinctive hatches instead of solid color fills.
Could anyone tell if whether this would be possible, and how difficult to implement. If possible, what files in the code would be relevant ? I have no knowledge of the codebase ATM.

[pebogufi]

Did you try map mode night ?
Don't know whether it is better.

[pshunter]

Sure, a more contrasted custom stylesheet is already better for roads. Problem is, it's hard to tell apart e.g. forest, meadow, water because of the lack of color, it falls back to hard to distinguish grey shades. Using hatches at various angles and spacings, cross hatches or even other shapes like tiny waves for water could solve this very nicely. It could even improve readability of the color map by enabling to put in more details, or use less color shades.

[vshcherb]

Rendering styles are fully customizable probably it worth to start a style and replace some constants first of all.

[pietervdvn]

Hey, is this perhaps one of those onyx-boox that you have?
I have one as well and some experience customizing, we could work on something?

[naoliv]

Maybe a style like this http://maps.stamen.com/toner would be useful for you (but someone would still have to implement it for OsmAnd)

[pshunter]

@pietervdvn
Almost. Mine is one of these newer likebook mimas. Same screen AFAIK. If you already have some customized stylesheets (?) for your device, it would be good input about what can be done now.
@naoliv
Yes this is a good example, however it is not very detailed and I found only one type of dither used. E-ink screens should be used to cram a maximum information on the map, like paper maps used to. No color means that we have to use smart variations on full, dashed or dotted lines to distinguish between features. to be readable, I guess maximum 2 grey shades apart from solid black or white can be used.

[mezzarobba]

Hi,

Thanks a lot for your work on this great application!

I tried using it on an e-ink device as well. I found both the standard osmand style and the topo map style usable, but I'd be willing to help create and test a style really suitable for e-ink displays.

Something else that makes osmand unpleasant to use on this kind of device, though, is the frequency of redraws, even with animations disabled. It would be really great if there was a way to limit scrolling to large discrete steps (1/3 to 1/2 of view size), draw the map in just one or two passes instead of displaying a number of layers one after the other, and drastically reduce screen redraws while scrolling or zooming.

[mmveets]

I have the same need, for navigation on an e-ink device, and would love to see this, and to help if I can.
FWIW, I've tried the Nautical map style from a more recent update, and found that it works nicely for contrasting a route to be followed against the surroundings. In other styles, the dark coloring of streets would make it hard to distinguish the route, at a glance. The nautical style has an overall orange tone for cities, so it would help even more to customize that by lightening it up a shade (yellow?), at least on my device.
Also FWIW, my use case is a Yotaphone mounted on a bike. The e-ink display is great for navigating during the day (no glare) and with low battery usage.