Sun Seeker Update v1.5

As part of a series of planned updates for the Sun Seeker augmented reality iPhone app, the latest update v1.5 has just been approved by Apple.

For a video demo of Sun Seeker see this earlier blog post.

The main changes for v1.5 are:

• Enhanced performance for smoother compass dial rotation
• Added new table of annual rise and set times
• Added new table of sun’s daily azimuth and elevation
• Added tap action to rise/set label to see local times instead of intervals
• Better handling of disabled Location Services
• More efficient use of GPS – now only used briefly on startup
• Fixed some minor bugs and issues with date changes

[Note - v1.5.1 update has been submitted to fix OS3.0 backward compatibility and missing sunset times for some locations west of GMT.]

Following is a more detailed description of some of these items.

1. Enhanced Compass Dial Rotation

The compass dial in Sun Seeker includes text which retains its orientation relative to the device regardless of the compass rotation, and this means that at least part of the image needs to be re-rendered for each incremental rotation of that dial as the compass rotates. Previously the whole image was being redrawn each time, and that performance hit meant that the dial motion was quite jerky when it needed to make large rotational changes. The new implementation involves much less redrawing, and hence allows the compass to be much more responsive.

2. New Tables

The table of rise and set times spans the entire year, and hence allows you to look up rise and set times for any given date.

The table of the solar path lists the sun’s azimuth and elevation at 15 minutes intervals throughout the currently selected day.

3. Tap action to see rise/set time instead of intervals

This was added simply for clarity. Tapping on the rise/set labels on the compass screen toggles the display between showing the rise and set time in local time versus showing time duration between now and the rise and set times.

4. Better handling of Location Services status

A problem to date has been if the user has switched off the device Location Services or (perhaps accidentally) disabled them for this particular app. In these cases the app can only use its last acquired location data, and in this case the app shows data which is correct for that old location, but incorrect for the user’s current location.

This issue has been the biggest generator of email support requests to date, but I now expect that this will lessen considerably, because I have implemented clear warning messages which pop-up whenever location services are disabled, each time that the app starts up or resumes from background.

5. More efficient use of GPS

Previous versions of the app left GPS on continuously while the app was active (although off when inactive or in background), and this presented the app with ongoing positional updates while it was open. But for the sake of efficient use of GPS, it seemed unnecessary to leave it on once the location had been determined to a reasonable accuracy, so GPS is now only on as long as location has not been found to reasonable accuracy. However an important point here is that the app should re-query its location not only every time it starts up, but also whenever it resumes from background. The reason for this of course is that the device may have changed location while it was in background – for example it may resume from background after the user has traveled somewhere by air!

6. Future Updates

By far the most common request from users has been to allow selection of other cities/locations rather than just the current current, and this is the next major feature planned. But please note that it is not a trivial update! A particular difficulty here is in ensuring that the local times reported for other locations respect the correct timezones and daylight savings rules for those locations throughout the year. However, I do have a solution planned, and hope to be able to do this within a reasonable timeframe.

The next most common request has been for an Android version. Due to the particularly technical nature of the app, and the fact that I personally have no grounding in Android development, this is a much more difficult proposition. However I have been looking to outsource it. I apologise to those who have been waiting impatiently, and I can assure you that these plans are progressing.

In the meantime, I hope you continue to enjoy the app!

See Breeze – Augmented Reality Wind Visualizer for iPhone and iPad

Ajnaware’s latest app “See Breeze” has just been approved by Apple, and is now available from the app store. This app has a universal binary – so can be installed onto either iPhone 3GS or onto iPad from the same purchase.

Like Sun Seeker, this app pushes the boundaries of what augmented reality on mobile devices can be used for. The app description is as follows.

Provides both a FLAT VIEW COMPASS and an AUGMENTED REALITY 3-D VIEW showing the local wind and weather conditions with animated wind vectors.

Ideal For:
- Aviators, Sailors, Surfers, Windsurfers, Kite Flyers, Cyclists, Fire Fighters, Weather Hobbyists and any other outdoor enthusiasts

Main Features:
- Compass view showing animated wind vectors for nearest weather stations with wind, temperature and humidity readings
- 3-D augmented reality view with animated wind vectors
- List of local observation stations (up to 10 nearest), from which any may be selected for individual wind viewing
- Map view of all local stations with weather arrows showing direction, speed and temperature
- Uses official Bureau of Meteorology data within Australia, and NOAA metar data (from airports) for rest of world

Feature Device Dependencies:
- iPhone – interface runs only in portrait mode, 3-D View is shown as an overlay on the camera view
- iPad – interface runs in any device orientation, 3-D View is displayed with an opaque background (due to absence of camera)

I had the idea for this app about the same time as I had the idea for Sun Seeker, but I had to choose just one to do first, and even when I did start it, I found that it took a lot longer than expected due to the various technical challenges involved. The first major challenge was learning some OpenGL ES, and the second one was figuring out how to get OpenGL ES to respond correctly to device orientation and heading changes. Many thanks to Jeff LaMarche for some great blog articles on the former, and as for the latter, I pretty much had to figure it out for myself. I did post on Stack Overflow, but ended up answering my own question.

Adapting the app to iPad was also an interesting issue to deal with. I ended up with quite a few conditional branches in the code to deal with cosmetic differences. But the end result more than justified the extra effort. It looks superb on the iPad. Credit for the excellent app artwork goes to Peter Fellows once again, whose work on the Oz Weather program was brilliant. Here are a few screenshots from the iPhone app.

and one from the iPad app, which of course has much nicer mapping ability…