[done] Zooming and pixelization

You can tell us what you like or don't like in AlpineQuest, and what you would like to see in future releases.
CRider

[done] Zooming and pixelization

Post by CRider » Thu Jan 10, 2013 6:53 pm

Hi,
When I zoom in / out with multi touch, most of the time the map appears pixelized. When I use + and - buttons, the map is displayed fine.
As a result, I cannot have a good displayed map corresponding to a zoom level that doesn't match the + and - levels.

It looks like the map is stored as a bitmap for the set of + and - zoom levels.
For a satellite map, this makes sense.
But for a vector map (google map or open street map), this is very annoying.

Am I missing something ?
Thanks.
Regards.

Psyberia-Support
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Re: Zooming and pixelization

Post by Psyberia-Support » Thu Jan 10, 2013 10:16 pm

Hi,
Actually all maps are "bitmap" maps. AlpineQuest doesn't generate maps, it only retrieve them from servers, store and display them. The map servers (Google Maps, OpenStreetMap, ...) only generate the maps at fixed zoom levels (each following zoom level double the precision of the previous one).
These fixed levels are displayed when you use the +/- buttons, however between this levels, the previous map has to be scaled, that's why it may look pixelized depending on the map quality.
Unfortunately I can't see something to do, except to forbid to zoom the map between two zoom levels (that's what other applications do).
Best regards
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CRider

Re: Zooming and pixelization

Post by CRider » Fri Jan 11, 2013 10:10 am

Hi,
1. Google Maps (the app) and My Tracks both display (Google) maps nicely at any fine zoom level. I guess those apps rely on vector maps or some special Api.

2. With the current display of map, it could be convenient that the resulting zoom level of the multi touch gesture is at the end adjusted to the closest "good" zoom level.
The real time bitmap zoom is handy for giving a feedback to the user during his/her multi touch gesture and should be kept.

Thanks.
Regards

CRider

Re: Zooming and pixelization

Post by CRider » Sun Jan 13, 2013 11:33 am

Hi,

Any feedback on the suggested "zoom snapping" feature ?
CRider wrote: it could be convenient that the resulting zoom level of the multi touch gesture is at the end adjusted to the closest "good" zoom level.
The real time bitmap zoom is handy for giving a feedback to the user during his/her multi touch gesture and should be kept.
Thanks
Best regards.

Psyberia-Support
Site Admin
Posts: 4943
Joined: Wed Apr 14, 2010 9:41 pm

Re: Zooming and pixelization

Post by Psyberia-Support » Sun Jan 13, 2013 9:49 pm

Hi again,

Yes you're right, newer versions of Google map allows you to select any value of zoom since it now uses a vector map. AlpineQuest uses the maps from the web servers, and handle them as images, whatever they contain (roads, satellite images, topo, ...).

Concerning the closest zoom level selection, that's already more or less the case. If you display the map scale, you will also see the current level scale (the value between parentheses), which usually goes from x1/2 to x2.
Depending on the scale range between two consecutive zoom levels, the level scale can be bigger, the the map can look more pixelized as you are describing.
These value are also adapted based on the device pixel screen density.

Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

CRider

Re: Zooming and pixelization

Post by CRider » Wed Jan 23, 2013 9:19 pm

Hi,
AlpineQuest wrote:Yes you're right, newer versions of Google map allows you to select any value of zoom since it now uses a vector map. AlpineQuest uses the maps from the web servers, and handle them as images, whatever they contain (roads, satellite images, topo, ...).
Do you intend to support such vector map in the future ?
AlpineQuest wrote: Concerning the closest zoom level selection, that's already more or less the case. If you display the map scale, you will also see the current level scale (the value between parentheses), which usually goes from x1/2 to x2.
I agree that the current level scale is useful. But it's not always easy to set this level scale exactly to x1.0 with the pinch-to-zoom gesture. That's the reason why I'd like to have an automatic selection of the closest x1.0 zoom level when I finish my pinch-to-zoom gesture. This automatic selection could be enabled via a setting preference.

Thanks,
Regards.

Psyberia-Support
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Posts: 4943
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Re: Zooming and pixelization

Post by Psyberia-Support » Thu Jan 24, 2013 10:34 pm

Hi again,
For the vector maps, there is a very little chance... Topo maps are usually in raster formats, whereas vector maps are much useful for drivers (it's needed for turn to turn directions). Moreover, the only vectorized data source available is OpenStreetMap, which is good but far as complete as local topo maps.

Concerning the auto "pinch lock" feature, it's a good idea. It won't be in the next version (which is under testing), but I'll try to put it in the next one.

Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

Psyberia-Support
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Re: Zooming and pixelization

Post by Psyberia-Support » Thu Jan 24, 2013 10:40 pm

Another thing I realized today: the built-in maps only contains one map level over two (if you compare with the levels available on the respective websites, not all levels are available).
This have been done to reduce the amount of cached data on user device, but on the other hand it expends the gap between levels. It can be why you can find the map so pixelized.
I'll have a look at the opportunity to add all levels.
Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

CRider

Re: Zooming and pixelization

Post by CRider » Fri Jan 25, 2013 1:32 pm

Hi,
With additional / intermediate zoom levels and the auto pinch-to-zoom feature, I won't miss vector maps.
Thanks in advance
Best regards

Psyberia-Support
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Re: Zooming and pixelization

Post by Psyberia-Support » Thu Jan 31, 2013 8:16 pm

The version 1.3.8 has a new option to activate the use of all the levels for the online maps.
Be sure to restart the application after changing this parameter.
I'll try to add the "auto pinch-to-zoom feature" in the next version.
Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

CRider

Re: Zooming and pixelization

Post by CRider » Fri Feb 01, 2013 10:19 pm

Hi again,
Thanks for the additional levels.
But it seems that the behaviour of the current zoom level has changed. When I use only the + and - buttons (so no pixelization), the current zoom level is ×0.67 ! I was expecting to have ×1.0. Am I missing something ?
Regards

Psyberia-Support
Site Admin
Posts: 4943
Joined: Wed Apr 14, 2010 9:41 pm

Re: Zooming and pixelization

Post by Psyberia-Support » Fri Feb 01, 2013 11:58 pm

Hi,
It's due to the fact that you have a high pixel density screen.
On Android 3.2 and more it was not well detected, in this version it's corrected. Now the "High resolution map" setting is activated, so you have 1.5x more quality, so the map can un-zoom properly until x1/1.5=0.67.
You can un-check the setting if you want to get the previous behaviour.
Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

CRider
Posts: 126
Joined: Sat Feb 02, 2013 2:23 pm

Re: Zooming and pixelization

Post by CRider » Fri Apr 26, 2013 6:25 am

Hi,
I've noticed by chance that you've implemented the auto pinch lock feature in 1.4.0.
It's awesome and it would have deserved some indication in the release notes.
I've also noticed that you have removed some preference settings related with high res map. I guess the app now uses the most relevant settings for the device.
Thanks for all these improvements.
Regards.

Psyberia-Support
Site Admin
Posts: 4943
Joined: Wed Apr 14, 2010 9:41 pm

Re: Zooming and pixelization

Post by Psyberia-Support » Sun Apr 28, 2013 11:39 am

Hi and thanks for your feedback,
Yes you're true it hasn't been much indicated.
After your request, I have made this feature as optional, but after using it I found it nice. So it's now activated by default.
However I already received a complaint by email, so I will add an option to disabled it (right now you can disable it using another way described below).

As you noticed, I have also removed few settings, as I always try to keep only the most important ones not to increase the complexity.
However I have added a new feature, called "user settings" that I need to document.
In one word, you can tweak more settings using a file placed in the AlpineQuest folder. It allows to add more capabilities that are only needed in particular cases or for just few users, without adding more and more settings in the Preferences window.

Right now, you can disable the "auto pinch lock", the map sliding, add a custom location display, and other things.

Based on that, I have added the ability to activate the save of all data in GPX files (accuracy and pressure as we talked about), when exporting tracks and when copying/pasting. As a result, I have removed this option in the track export dialog.
To activate this mode, you can create a file called "user_settings.conf" in the AlpineQuest folder (usually "/sdcard/alpinequest/"), and add this line:

Code: Select all

landmarks.features.offlinelandmarks.formats.gpx.full_export=1
You should see "1 user settings loaded in..." in the log file when starting the application.

I'll try to document all this soon.
Best regards
Do you like AlpineQuest ? Leave a small comment on Google Play !

CRider
Posts: 126
Joined: Sat Feb 02, 2013 2:23 pm

Re: Zooming and pixelization

Post by CRider » Mon Apr 29, 2013 7:54 am

Hi,
AlpineQuest wrote: In one word, you can tweak more settings using a file placed in the AlpineQuest folder.
You're right in separating general settings from extra / advanced settings.
However, instead of a file, I would have preferred an extra or advanced settings page that would be displayed by a dedicated button from the main settings page.
I don't find editing a file on a smartphone really convenient.
It's just my humble opinion. I can live with the settings file :-)
Regards.

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