Knaģa emuāri

A new version of OfflineCacher has been published. The instructions are still the same and are available from previous post. The same post has more information on what OfflineCacher can do. In short – it is an Windows Mobile Smartphone application to enable geocaching from your mobile phone without ever using the GPRS (data) connection – this is really useful when traveling as roaming charges most of the time are through the roof.

Download:

• Desktop application 504Kb (map downloader, no installation required);
• Mobile application setup 350Kb (run the .cab file from the mobile phone).

Changes in this version:

• The cache storage is changed from a simple XML file to a SQLite database. This means that the application can work with lot more caches without eating all of the memory and startup time will always be constant – previously it could take even 20 seconds to load with 200 caches.
• Download process is now made paralel and in total runs up to 4 times faster. It is also now possible to cancel the whole download or only part of it (for example, if you do not need the satelite maps).
• The cache description is loaded correctly – previously only the long description (second part) was loaded and short description was ignored. This caused incomplete cache instructions to be displayed on the device.
• Changed to download also the cache images not only images from logs. But still only the last 20 images are downloaded.
• Turning off and on the GPS works correctly without restarting the application. Previously turning off worked fine but after turning it back on the application had to be restarted.

The work continues to enable the application to load and store more than 2000 caches at the same time with as much maps as possible. The first step has been done – it is now possible to store many caches at the same time, the next version will contain changes to how maps are stored to use the limited capacity of storage cards as effectively as possible.

It could be possible that some cache filtering options do not work correctly but my weekend caching session did not turn up any major issues.

The change from XML to SQLite also means that whatever caches you had loaded previously will be lost and you will have to load them again. As all .gpx files are not deleted but copied to the Processed directory, you can just move tham back up and the application will load them.

Pētot, kā priekš savas slēpņošanas programmas iegūt Latvijas topogrāfiskās kartes, uzdūros LĢIA karšu serverim. Kas mani iepriecināja – pārsteidzoši aktuāla informācija – laukos kaimiņa nesen izraktais dīķis (ar kuru viņš appludināja daļu mūsu meža) ir jau iezīmēts.

Taču reizē ar to uzzināju kaut ko jaunu – Latvijā šādām kartēm neizmanto vis kādu no standarta koordinātu sistēmām (UTM vai WGS84 – šis ir visbiežāk sastopamais formā N 56’ 23.233’’ – to nedaudz citā pierakstā izmanto arī Google Maps un citi), bet gan savu standartu LKS-92. Cik nu varēju izlobīt, tad tas pēc būtības ir tas pats UTM, tikai, lai to izmantotu, aprēķinos ir jāizmanto specifiskas konstantes. Katrā ziņā problēma ir vienkārša – ja man ir koordinātas WGS84 formātā, uz šādas kartes tās uzlikt tik vienkārši nevar.

Pameklējos internetā, uzdūros boot.lv foruma rakstam par tēmu. Tajā atbilde netika dota, taču bija norāde uz konkrētu resursu, kurš pārrēķina ievadītās koordinātas starp dažādām sistēmām, tajā skaitā LKS-92. Tā kā visi aprēķini tika veikti JavaScript-ā, tad ar salīdzinoši nelielu darbu esmu ieguvis C# kodu, kas pārrēķina starp WGS84 un LKS-92.

Pirmkoda lejupielāde

Arhīvā ir divas klases: PointD ir vienkārša struktūra X/Y vērtību pārim, bet LKS92andWGS84 satur divas metodes konvertēšanai starp LKS-92 un WGS84 koordinātu sistēmām.

Pilnīgi nejauši uzgāju “fīču” iekš YouTube, kuras tur, manuprāt, agrāk nebija. Nospiežot uz “CC” pogas zem video agrāk tika piedāvāti subtitri, kas tika pievienoti pašam video. Tagad te parādījusies iespēja radīt subtitrus automātiski, izmantojot Google balss atpazīšanu. Jāsaka, ka rezultāts ir salīdzinoši labs, atceroties eksperimentus ar Windows 7 iebūvēto balss atpazīšanu, šeit kļūdu ir mazāk un tās nav tik šausmīgas.

Iepriekš rakstīju par jautrībām, kas iestājas, ja VPN tīkla IP adreses pārklājas ar lokālā tīkla IP adresēm. Toreiz secinājums bija, ka Windows 7 atšķirībā no Windows XP ar to tiek tīri labi galā. Šodien atklāju, ka ir viens gadījums, kad arī Windows 7 padodas.

Problēma rodas gadījumā, ja caur VPN savienojumu cenšas pieslēgties serverim, kura IP adrese sakrīt ar lokālo IP adresi (to, ko iedalījis WiFi u.tml.). Šajā gadījumā arī Windows 7 cenšas pieslēgties pie lokālā datora un nevis pie servera. Teorētiski neko nevar pārmest, taču galvassāpes tas var sagādāt, jo pēkšņi bez nekāda acīmredzama iemesla kāds serveris nestrādā.

Viens no risinājumiem ir mēģināt dabūt jaunu IP adresi, bet, tā kā DHCP adreses parasti tiek piesaistītas MAC adresei uz vismaz nedēļu, vienīgais variants ir mainīt lokālo MAC adresi (ja vien nav pieeja rūterim). Taču vismaz manai WiFi kartei tādas opcijas nav. Ja ir pieeja rūterim, tad pareizāka rīcība ir nomainīt lokālā tīkla IP adreses uz kaut ko pavisam random, piemēram, kaut ko no 10.x.x.x apgabala. Ar šādām adresēm ir krietni mazāka iespēja uzrauties uz šo problēmu, salīdzinot ar 192.168.0.x, kas ir noklusētās adreses vairumam rūteru.

OpenStreetMap nenoliedzami ir ļoti, ļoti vērtīgs projekts. Piemēram, kājiniekam vai riteņbraucējam šī karte ir noderīgāka par Google Maps, jo pēdējā praktiski vispār nav atrodamas dažādas takas parkos utt.

Taču community veidotai kartei (nav gan izslēgts, ka arī citās kartēs ir tāpat) ir arī dažādas kļūdas. Piemēram, koordinātās 0;0 (netālu no Āfrikas krasta, kur ekvators krustojas ar 0 platuma grādu) OpenStreetMap ir ierakstīts “South Pole”. Korektās koordinātas ir –90;0, acīm redzot kāds ir nokļūdījies. Man pagāja laiciņš, kamēr sapratu, kāpēc kartē redzu dienvidpolu.

http://www.openstreetmap.org/?lat=0&lon=0&zoom=16&layers=M

A new version of OfflineCacher has been published. Installation instructions and download links can be found in the previous post.

Main changes:

• saved cache web page can be opened from Windows Mobile 6.5;
• custom caches/waypoints can be created for given coordinates or on a specific point on the map.

For initial description and reasoning behind the OfflineCacher application, see the previous post. In short – OfflineCacher is a Windows Mobile Standard (otherwise known as Smartphone) application for geocaching without using data (GPRS/EDGE/…) connection. Both maps and additional cache information is predownloaded on the desktop and copied over the wire to the phone.

Note: the instructions below are constantly updated when new version is released.

Requirements:

• Microsoft .NET Framework 3.5 SP1 on the desktop;
• Microsoft .NET Compact Framework 3.5 on the mobile phone (the link is for a desktop application that during install allows you to install the library on the phone (via ActiveSync);
• Premium Membership on geocaching.com to download .gpx files.

Download (current version is v.5):

• Desktop application 522Kb (map downloader, no installation required);
• Mobile application setup 357Kb (run the .cab file from the mobile phone).

Setup:

• unzip the desktop application – no further setup required, just launch it;
• on the mobile phone storage card create directory \Storage Card\OfflineCache (the directory goes directly on the storage card, the given path is when accessed from the phone itself) – it cannot be changed currently;
• it is recommended to either use a card reader or switch the phone to work as a removable drive and not via ActiveSync (otherwise the copy speed will be extremely slow and during the copy it will automatically overwrite files and not leave existing ones; also via ActiveSync the desktop application will not be able to directly connect to the phone).

Typical usage:

• download .gpx file from geocaching.com (either individual cache or a pocket query) to a local folder – specify this folder in the desktop application; alternative is to download .gpx files to the OfflineCacher data folder under Caches subfolder.;
• connect your phone via USB connection, set it up so it does not use ActiveSync;
• create the OfflineCacher folder on the memory card – this way the download application will detect it automatically and work always even if for some reason Windows decides to give the card different drive letter later;
• launch the downloader application, select the removable folder option (if required, browse for the folder), it will automatically read the .gpx files and display the caches on the map;
• navigate the map by mouse (right click centers the map, double left zooms in, double right zooms out);
• select the caches you want to visit either from the list or from the map;
• click “Download maps and extras” – this will download maps for all zoom levels (only the deepest for sattelite map) for all selected caches – approximately 3x3 mobile screens are predownloaded; it will also download the cache web page with all logs (the .gpx includes only the latest ones) and images;
• launch the the mobile application, it usually takes about 5 seconds to load (no matter the number of caches);
• usage of the mobile application is via the menus and keyboard shortcuts:
  • “1” – zooms out;
  • “3” – zooms in;
  • “0” – centers on GPS coordinates, second click zooms in on GPS coordinates;
  • “Enter” – opens the selected (under the center of the screen) cache info page.

The usage of this application might seem a bit complex at first but after the first time it should be very straight forward – it is this complex because of the requirement to predownload maps – once you start copying the maps to the storage card you will understand why it is better to be done this way – the size of them is quite large and if that is downloaded from the mobile phone, the bill can grow quite a bit.