Spot GRIB Request

saildocs provides support for the Spot GRIB requests. Spot requests returns forecasts for a given location. Let's say you just dropped the hook, and you want to know what your night is going to look like...
If you send an email to query@saildocs.com, with a body like this:

 send spot:37.5N,122.5W|5,3|PRMSL,WIND,RAIN

, you will receive a response like that one:

Data extracted from file gfs130704-12z.grb dated 2013/07/04 16:52:56
request code: spot:37.5N,122.5W|5,3|PRMSL,WIND,RAIN

Forecast for 37°30N 122°30W (see notes below)
Date  Time  PRESS  WIND DIR RAIN
        utc    hPa  kts deg mm/h
----------- ------ ----- --- ----
07-05 00:00 1005.7  9.8 288  0.0
07-05 03:00 1005.7  11.5 297  0.0
07-05 06:00 1006.8  12.9 302  0.0
07-05 09:00 1006.7  13.0 303  0.0
07-05 12:00 1006.7  12.6 303  0.0
07-05 15:00 1007.0  11.7 299  0.0
07-05 18:00 1007.7  10.3 280  0.0
07-05 21:00 1007.2  11.4 270  0.0
... etc

This is "human readable", as they call it, but not that catchy, hey?
The cool thing is that this content can be parsed, using basic regular expressions.
If you drop the content of the request's response in the box below, you will have a chance to render it visually.
See in full
The browser you use must support HTML5 for that.

Reviving the Weather Wizard Applet

It needs to be signed (to be trusted)..., but give it a try: here (in full), or below (in small).

This demonstrates a small subset of the features of the Weather Wizard. There is no GRIB, no routing, no possibility to save anything.
But that gives you a taste of the possibilities.

The applet is signed. That means it wants to get out of the Sun sandbox. Namely, it wants to read the faxes from an external website.
Once you have selected your composite (from the top drop-down list), do not forget to hit the "Go" button...

Version(s) 3.0.1.3

Released today the version 3.0.1.3 of the Weather Wizard, the Navigation Desktop, and the Polar Smoother.
The release includes some bug fixes, cosmetic improvements, and a decomposition of the deviation curve (in the NMEA Console), as shown below.

Click the image to enlarge.

And with the NMEA re-broadcast, the Navigation Console works like a charm with OpenCPN 3.1.1328.

OpenCPN 3.1.1328 released

A new beta of OpenCPN has just been released, it supports other channels than Serial for the NMEA data input. TCP, UDP, GPSD... That means that if you read the NMEA port from the Console, you can re-broadcast them on another channel that OpenCPN can listen to; no more Serial port access conflict, the two applications can run simultaneously, that is very cool. That also means that when you replay logged data in the console, you can visualize them in OpenCPN too. Even better!
AIS Data can also be read this way. The San Francisco Bay traffic can be seen by using a TCP connection on 207.7.148.216, port 9009

Custom Micro Pattern

The micro patterns rely on two main features:

• A background
• GRIB Smoothing

The GRIB Smoothing is not a problem, and the value it can take are now available in the pattern editor.
The problem can come from the backgrounds. Up to now, they refer to an image, part of a jar, accessed through a getResource() method.
In order for the user to be able to come up with his own patterns, there is now "protocol" for the background.

Click the image to enlarge it. Notice in the fax URL (a background is just a non-transparent fax), it begins with ext-resource://.
Whatever is after that is the URL of the image you want to set as a background. In this case, it is picked up in the resources directory. But it can come from the web as well, it just has to begin with http://...
Notice beside the "Projection" drop down list, you now also have the possibility not to display the chart contour.
The GRIB smoothing parameters we talked about before are the 2 last parameters at the bottom of the dialog displayed above.

Micro Patterns

Combining the chart backgrounds and the GRIB smoothing, we can come up with a local pattern, which can actually make some sense, specially for local conditions (wind and kite surfers might be interested).

The image above is the display of the following request:

  GFS:42N,32N,128W,116W|1,1|0,3..168|PRMSL,WIND,HGT500

It is displayed with a GRIB 2D smoothing of 6 (cells are 10x10 nm) and a time smoothing of 3 (one frame every hour). The total time is one week, that makes 168 frames.
At the entrance of the San Francisco Bay, the wind goes from WSW on Wednesday at 06:00 UTC, to South and 12:00 UTC, to North on Friday at 00:00 UTC. Interesting...
This feature - and the associated background - will be available soon, in the next patch version of the software.

Digital Image

This is indeed what you can call a digital image... Just take a step back in case it is not obvious to you. Or forward actually, it depends on what you missed. ;0)
Click here to see it in full.
You can do your own, just go to text-image.com.

Routing now avoiding land

Sounds obvious, I know, but the routing is now - on request - able to avoid land.

The feature is being developed - ie it works on my machine - and will be available in beta soon (in 3.0.0.5).
There will be some limitations for the inland seas, like Caspian, Aral, Black Sea, Great Lakes... But that should beOK for the rest of us.
As always, the code will be available on Google Code.

Google Locator for everyone

The Google Locator is this application we used during the trip to show our position on Google Maps in the blog (this blog) we were feeding from SailMail.
It is now available to whoever wants to use it, you just have to register.
To register, go to http://donpedro.lediouris.net/php/locator/idform.html and fill out the form.
(All images below are clickable, to enlarge them)

Once this is done, you can use the Google Locator available in the Navigation Desktop. You need to set your Boat ID in the preferences

When you hit the button "Generate URL", the URL you need is in the clipboard.

You can paste it in an email, or use it as it is. Here is the kind of renderings it produces in a browser

You can try it for yourself.
Enjoy!

How SailMail works

By popular demand... here is a quick post explaining how we can send and receive emails when at sea. We have been successfully using SailMail.
The SSB is using an analogous signal. Emails are digital data. That is why you need a modem (MOdulator-DEModulator) between the radio and the laptop, to convert the analogous signal into a digital one, and vice-versa.

So, on the boat, you need: a laptop, a modem, an SSB, with its antenna. You also do need the SailMail client program, which knows how to communicate with the modem and the SSB. All details about that are given on the SailMail web site.

The SailMail association has a network of land radio stations, which can receive the signals emitted by the boats. The land stations also have a modem, and are connected on the Internet. The emails rely on the Internet. It is like if the land stations had two faces: one facing the sea (with the SSB), and one facing the web (with the Internet connection).

What happens when the boat sends an email:
On the boat, you compose your email, and you put it in your outbox. Then you turn your SSB on, and you use the SailMail client program to contact a land SailMail station.
When the contact is established, the messages sitting in the outbox go through the modem and the SSB to be streamed to the land station. On receive, the land station then turns the messages back into digital files, and uses its Internet connection to post them on the web. From there, it's the usual email story.

What happens when an email is sent to the boat:
Someone has been sending the boat an email, using its @sailmail.com address.
When boat is establishing a connection with a land station - just like above - the land station is converting the digital emails sitting in your SailMail inbox into an analogous signal, so they can be streamed to the boat.
On the boat side, when those messages are received, they're converted into emails, and put into your SailMail client inbox on your laptop. That's it!

The radio transmission is very slow, compared to what DSL and others can provide.
Remember the dial-in time? Well, divide it by ten, and you're not even close...
That's why SailMail is appropriately cutting any attachment to the incoming emails..., and that's why, if you reply to a SailMail email, please do not hit the reply button without cutting the original message! Thank you.
A SailMail subscription grants you 90 minutes of transmission per week. Transmission time also include the time it takes to receive unwanted messages (like the original message, the one you replied to without cutting it). Thanks again.