ShralpTide  a tide clock and tide predictor for mobile devices
    Version 1.0.0

    Copyright (C) 2009  Michael Parlee

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
    
    The tide prediction algorithms contained in this software are
    derived from XTide 1.6.2. For more information please visit the
    XTide website. http://www.flaterco.com/xtide

THIS PACKAGE IS AVAILABLE FROM:
http://github.com/shralpmeister/shralptide

Introduction
------------

ShralpTide provides a reduced feature set of the excellent Unix
command line tide tool, XTide, in a format accessible to the casual
beach goer on the iPhone mobile platform.

Hardware and operating system requirements
------------------------------------------

ShralpTide can be run only on an Apple iPhone or iPhone simulator. 
The iPhone simulator requires an Intel-based Mac running Mac OS X 10.5
or newer.  It can be obtained free of charge from Apple as part of the 
iPhone SDK at http://developer.apple.com/iphone. Registration is required.

ShralpTide can be installed using the iTunes App Store or by using Apple's
iPhone SDK. Using the SDK it is possible to install it on the iPhone 
simulator or on an iPhone provisioned with a Development key.

Usage
-----

Once installed the ShralpTide icon will show up on the iPhone home screen.
Press the icon with a finger to launch it.

Launching ShralpTide will bring up a utility style interface. It takes a few
seconds to load so be patient. Once it has finished caluculating tides you
can scroll sideways between the days. Dots at the bottom of the screen show
the number of pages -- the highlighted dot showing the position of the
current page.

The first page shows today's tide. The tide level closest to the current
current time is displayed at the top with an upward pointing arrow indicating 
an increasing or flowing tide and a downward pointing arrow indicting a
decreasing or ebbing tide.

Turning the device from a portrait to landscape orientation will display a
plot of the tidal movement for the selected day. If the present day is 
selected a red line or cursor indicates the current time. In the bar at the
top of the screen the tide level and associated time are displayed. Touching 
the screen causes the cursor to jump to the point of contact and the tide
shown at the top of the screen changes to reflect the tide level at the 
point in time nearest the cursor. This works the same for the following days
except that the cursor rests on midnight instead of the current time.

When ShralpTide is first launched after installation it calculates tides for
the default tide station at La Jolla, California. To choose the location
nearest you touch the location icon at the bottom left of the portrait mode
display. This feature will ask the iPhone or iTouch for its location and
query the tide stations for those closest to that location. The display will
flip over and display a list of those locations sorted in descending order by
distance from the current position. This is most likely to succeed on an 
iPhone with GPS or good cell reception and most likely to fail on an iPod
touch. 

If the device doesn't return a location the globe icon on the bottom right
of the portrait display will allow selection from a list of all the tide
stations world wide. Typing the name of a location in the search field will
filter the list. The last tide station selected will be remembered as long
as ShralpTide remains installed on the device.

Installing from source code
---------------------------

To build ShralpTide from source an Intel based machine running Mac OS X 10.5
and the iPhone SDK is required. The iPhone SDK is available as a free download
from Apple's developer web site, http://developer.apple.com/iphone. The SDK
alone will be enough to build and deploy to an iPhone simulator. Additional
steps are needed to deploy on the iPhone itself. See Apple's website and do
some searching on the internet for available deployment options.

Download the source code from Github at 
http://github.com/shralpmeister/shralptide.

The source is available in both zip and tar.gz formats or you can clone the
git repository with the following command:

    git clone git://github.com/shralpmeister/shralptide.git

To build and run the project open the project, ShralpTide.xcodeproj, in XCode.

Select the "Debug - Simulator" build configuration. Click the build and run 
icon in the menu bar. The build will take a little while to finish. When
finished it will launch the Simulator, install ShralpTide, and run it.

Repeat the same steps but with "Debug - Device" to install it on your 
development iPhone.

Acknowlegements
---------------

Thanks to Dave Flater of XTide fame for providing excellent free software
and writing awesome FAQs.

Thanks to all the XTide contributers.

Thanks to Phill Tornroth and David Snow for motivating me to continue when 
I had already satisfied my curiosity.

Thanks to my wife Larissa and my children for putting up with my late nights 
of coding and graphics designing.

Contact Info
------------

Mike Parlee
shralpmeister@me.com