Nederlands
Deutsch (via google translate)
Introduction
In may 2010 I've got a new Oregon GPSr to replace my broken eTrex
CS. This new GPSr was missing proximity functionality I used to
calculate intersections of circles. Fortunately the Oregon is
capable of running Wherigo's making it a programmable device. This
prompted me to program a Wherigo to calculate intersections between
circles. This Wherigo has grown to contain more functionality and
has become
Wherigo Geocaching Tools or WGT for short.
Attention: This is a complex program. Initialising may
take some time. Also after updating for example the language or units it may take
a while before all updates are processed. Please be patient and
don't assume the cardridge has frozen.
Further the interface of the Oregon isn't as user friendly as I'd like it to
be. For example the numeric keypad is missing a dot (.). A lot of
people mistake the minus sign (-) for the dot. When entering
numbers WGT accepts the minus sign as a dot. For
example 116.88611 can be entered as 116-88611.
Main screen
When you start
WGT you will see on the main screen several items and
have three characters in your inventory. The items work as points on witch the operations work. The characters
are the objects that are capable of operations. Geometric operates on the points calculates
amongst other things the intersections. Converter converts strings and values.
Wherigo gives information about the
GPS and controls the configuration options. Quantities converts physical quantity to
several units of measurement. All these items en characters are
described in more detail in the next paragraphs.
Points / items
A number of actions are possible on Points.
Properties
The properties of a point can be changed with this action. After
selecting the properties action. Name The name of the point. The
prefix, x), cannot be chanced. Latitude The latitude (North,
South) or Y-coordinate of the point. Longitude The latitude (East,
West) or X-coordinate of the point. Radius When the point is used
as a circle, this is the radius of the circle. The center is
defined by the latitude and longitude.
Project
A point can be projected over a distance. When you select this
action, you will be asked for a bearing. The distance is the radius
of the circle you have set with the properties. When you project
the projected waypoint will be in the first zone. The radius of this zone will be equal to the
projected distance. After a projection, only the first zone is
visible and an eventual previous calculated coordinate in the first
zone will be overwritten.
Swap
You can swap points with either other points, zones or your current
location. When swapping with a point or zone, the name, without
prefix, location and radius are swapped. Prefix and image will
not be swapped. When swapping with the current location,
Here, the point will become the current location, the name the
current date and time and the radius the current accuracy of your
GPSr. Moving you to the position of the point will be implemented
when the license for Transporter
technology can be obtained from Starfleet.
Distances
When you select distances. You will be shown the distance between
this point and the other points. And the direction of those points.
Wherigo
The Wherigo character gives you
control and information about the cartridge.
GPS
Gives information about your current location, altitude and
accuracy of the GPS. This function may be removed in future
versions since most of these information can also be retrieved with
the "Swap Here" functionality.
Environment
Gives you environment variables like the Platform,
DeviceID, Device et cetera.
Language
Give you the opportunity to make WGT display a
language you (don't) understand. Thanks to
inkasso for the German translation.
Save
Saves the cartridge to and the settings so the next time you load
WGT your settings will be restored. Most players will
ask to save the cartridge when it is closed. This function is
useful when player on a device that doesn't ask to save the
cartridge or is buggy and frequently crashes. Remember Wherigo is
still in βητα.
Unlock
Gives you the unlock code to
unlock WGT on wherigo.com. When you select this
action, the status also becomes completed. So instead of entering
the unlock code, you can also upload the Save file.
Units
You can select your preferred units/format for Distance,
Bearing and Coordinates. The unit you select will be
used for input and display. For distances and bearings you can use
any unit you like, as long as you put the symbol behind the value.
For example 47 yd. If you omit the unit or use an unrecognised
unit, the unit you have selected will be used.
Coordinates
Coordinates are special. Regardless of you select H DDD.DDDD,
H DDD MM.MMM or H DDD MM SS.S,
WGT will recognise the format. The output of
coordinates is always in the by you selected format.
When you select Dutch Grid*, you have to enter the
coordinates in Dutch Grid. Dutch grid is only valid for x in
between -7000 and 300000 and y in between 289000 and 629000. If you
enter a value outside this range, an asterisk will be added. For
example: -50536 130922*.
*Rijksdriehoekscoördinaten
or RD for short in Dutch.
Bearing
The bearing can also be entered in cardinal directions: N(orth),
S(outh), E(ast) and W(est) and their subdivisions. For the Dutch,
instead of an E an O, for Oost and a Z for Zuid instead of S can
also be used. No more than three divisions (NNNW) will be
displayed. You can enter more, just like degrees where you can
enter 135.0884841043611, it will be used with that precision for
calculation but when displayed it will be rounded. For example:
when you enter NENNENEEEENNE it will be displayed as NE.
Converter
WGT can convert some common encodings.
ASCII / EBCDIC
Converts text to ASCII and
EBCDIC values, and back. You can enter the ASCII/EBCDIC values
either as decimal or as hexadecimal values. WGT will
try to guess you intentions. Ambiguous codes will be interpreted as
decimal. You can disambiguate the code by leaving out the spaces.
For example: 5463 When you enter text you also get the ASCII string
encoded as EBCDIC and vice versa. This is usually garbage.
Base
This function shows a number in different bases. The number can
also be entered in different bases. First you will be asked for the
base or radix of the number. If you enter an invalid value or no
value at all the default base of 10 will be used.
For example: Enter radius 16, you can now enter values in base 16
or hexadecimal. Entering the number 4EB will convert it to bases 2
up until 36. The binary representation of this number is
10011101011, octal: 2353 and decimal: 1259.
Caesar
Caesar's
cipher is one of the simplest and most widely known encryption
techniques. It is a type of substitution cipher in which each
letter in the plaintext is replaced by a letter some fixed number
of positions down the alphabet. For example, with a shift of 3, A
would be replaced by D, B would become E, and so on. This action
will preform all 26 possible substitutions on the text you've
entered.
Morse
Encodes and decodes
Morse code. A
dot is represented by "." and "-" is used as
dash. One or more spaces can be used as letter spacing, the short
gap. The medium gap, between words, is represented by a slash
/. If a message only contains Morse characters, the Morse
code will be decoded. If not, the text will be encoded in Morse.
Roman
Encodes and decodes Roman numerals.
When the text you've entered contains only digits, the number will
be converted to Roman numerals. If it also contains characters the
number is decoded back to decimal Arabic. Some remarks:
- When encoding to Roman, abbreviations like IV for 4 are used.
You can enter also the ancient representation IIII for 4, in fact
you can even use IIIII for 6.
- Although shortcuts MIM for 1999 disagree with the rule that
letters may only precede letters of the same order, MIM will be
converted to 1999. You can even push the subtractive principle to
it's limit. For example by entering IIVVVXXXXC. When you want to
convert 1999 to Roman numerals it will return the correct format of
MCMXCIX.
- Large numbers are commonly represented by a bar over the
characters, meaning the value of the letter will be multiplied by
1000. I = 1000,
V = 5000,
X = 10000, etc.
Since most GPSr's cannot handle overlines, the notation with
parentheses will be used. 90500 or IXD in Roman will be represented
as (ix)D. You can also use the parenthesis to enter large Roman
numerals.
Values
Shows the several values of a string. A=1, A=26, Vanity/SMS. As a
bonus also the rot13 and mirror (A=Z,
B=Y, C=X, etc.) conversions of that string will be shown. When a
number has been entered, the factorisation in prime numbers will be
calculated.
Viginère
Encodes and decodes the plaintext with the Viginère cipher.
Only letters wil be used. Any character that is not a letter will
be ignored in both the key as the plaintext.
Geometric
In WGT
the Earth is modeled as a sphere with a radius of 6371 km. A
'straight' line represents the shortest distance between two points
P1 and P2. On a curved object this generalisation is called a
geodesic. The
geodesic on a sphere is a great circle.
Distances
The distance command gives the great circle distance from point A
to point B. This is the shortest distance between these points. The
bearing from A to B and from B to A is also given. Only for very
small distances the difference between these bearings is 180°. The
shortest distance between the line A-B* and point C will
also be given. And the area of the triangle with vertices point
A, B and C.
*The line A-B is the great circle that goes
though points A and B.
Intersections
With the intersections command you can calculate the intersections
between lines and circles. The result will be shown to you as one
or two zones.
Lines
The lines are defined
by points. The first line by point A and B, the second by point C
and D. On a sphere any two lines intersect twice, these
intersections are known as antipodal points and are on opposite
sides of the sphere. WGT will give you the point
closest to the four points that have defined both lines. The radius
of the zone will be the maximum distance between the great circles.
If you want to calculate the intersections of lines that are
defined by a single point and a bearing, project that point over a
reasonable distance* and use this point as the second
point defining the line.
*No to small to have for accuracy, not to big
to confuse with intersection result will be returned. About
1000 km will usually do.
Circles
The circles
are defined by points with a radius. The first circle by point A
and the second by point B. When circles intersect each other, it
will be usually in two points. You are presented the point nearest
to your current location. Both points are available as zone in your
locations. The radii of each zone is the distance between these two
points.
Circle and Line
The line is defined by point A and point B. The circle by point C
with it's radius. Just like the intersection of two circles,
usually two points of intersection exists. And just like with the
two circle are you presented the point nearest to your current
location. Both points are available as zone in your locations. The
radii of both zones is the distance between the line and the center
of the circle.
Triangles
With three
points, a triangle can be
constructed. There are hundreds of different constructions that
find a special point associated with (and often inside) a triangle,
satisfying some unique property. Prof. Clark Kimberling has made an
extensive overview of these Triangle
Centers. Often they are constructed by finding three lines
associated in a symmetrical way with the three sides.
WGT can calculate (or approximate) a few of the most
commonly encountered constructions.
Incenter
An angle bisector of
a triangle is a straight line through a vertex which cuts the
corresponding angle in half. The three angle bisectors intersect in
a single point, the incenter, the center of
the triangle's incircle. The incircle
is the circle which lies inside the triangle and touches all three
sides. It is the largest circle contained in the triangle. The
radius of the zone is the radius of this circle.
Centroid
A median of a
triangle is a straight line through a vertex and the
midpoint of the
opposite side, and divides the triangle into two equal areas. The
three medians intersect in a single point, the triangle's centroid or geometric
barycenter. The centroid of a rigid triangular object (cut out of a
thin sheet of uniform density) is also its center of mass:
the object can be balanced on its centroid in a uniform
gravitational field. The centroid cuts every median in the ratio
2:1, i.e. the distance between a vertex and the centroid is twice
the distance between the centroid and the midpoint of the opposite
side.
Circumcenter
A perpendicular bisector
of a side of a triangle is a straight line passing through the
midpoint of the
side and being perpendicular to it, i.e. forming a right angle with
it. The three perpendicular bisectors meet in a single point, the
triangle's circumcenter; this
point is the center of the circumcircle, the
circle passing
through all three vertices. The diameter of this circle is the
radius of the zone when calculating the circumcenter.
Orthocenter
An altitude of
a triangle is a straight line through a vertex and perpendicular to
(i.e. forming a right angle with) the opposite side. This opposite
side is called the base of the altitude, and the point where
the altitude intersects the base (or its extension) is called the
foot of the altitude. The length of the altitude is the
distance between the base and the vertex. The three altitudes
intersect in a single point, called the orthocenter of the
triangle. The orthocenter lies inside the triangle if and only if
the triangle is acute. The diameter of the resulting zone will be
the current altitude according to your GPSr reading.
Snellius–Pothenot problem
Given three known points A, B and C an observer at an unknown
point P observes that the segment AB subtends an angle a and the
segment BC subtends an angle b; the problem is to determine the
position of the point P. The angle can be entered in the radius
field. Where the circumference of the Earth is 360 degrees. Thus
the radius is one radial and one minute one nautic mile. You can
enter angles easy by adding deg to the number or switching the
distance unit to Angle.
The Dutch astronomer and mathematician Willebrord_Snellius
Was the first to solve this problem. He calculated the position of
his house, by measuring the angles between the Pieterskerk,
City
Hall and Hooglandse Kerk.
WGT is also capable of solving the problem: Determine
the position of the point P given four known points A, B, C and D
an observer at an unknown point P observes that the segment AB
subtends an angle a and the segment CD subtends an angle c. So
solve this problem, enter a small (< 2', 2 NM or about
3.7 km) angle.
Quantities Most physical
quantities can be expressed in different units of measurements.
First select the physical quantity to want to convert. Then enter
that quantity in one unit. The result will be the same quantity in
a lot of other units.
Since I still haven't found a reliable way to show special
characters (high ASCII or Unicode), The degree symbol (°) will be
left out when showing and entering temperatures. Also when
temperature is expressed in Réaumur or Rømer, the accented
characters will be replaced by regular charaters. Their symbols
will become Re and Ro respectively.
Zones
The result of a geometric calculation will be stored in a
Zone. With a calculation also a radius is added. When you
enter of leave the radius of the zone, you will get a warning.
Easter eggs
WGT contains some Easter eggs:
- X marks the spot.
- The base of WGT is the crossing of the runways of
air base Gilze-Rijen.
- The default circles around each point and zone are intersecting
this cross.
- What are you saying?
- When the names of the points, including the prefix, x),
are pronounced the way the Dutch do. They sound like Dutch cities,
towns and hamlets.
- The default location of the points is located at those
places.
- The image is an areal photo of that place.
- Lunatic.
- The default locations of the zones are the landing places of
Apollo 11 and 12.
- The images show these landing places.
- ????.
- ????.
- ????.
- ????.
- ????.
- ??????.
- ??????.
- ??????.
- ??????.
Banners
Some banners to put in your profile, signature and other places.
| Cache banner, regular size: |
 |
<a
href="http://www.geocaching.com/seek/cache_details.aspx?guid=a765721f-bed0-4722-b576-7518a2847b36"><img
src="http://img.geocaching.com/cache/bd512958-35d7-40dd-96e3-73621cf8a367.jpg"
width="133" height="50" alt="Wherigo Geocaching Tools (GC2C308)"
border="0" /></a> |
| Cache banner, small size: |
 |
<a
href="http://www.geocaching.com/seek/cache_details.aspx?guid=a765721f-bed0-4722-b576-7518a2847b36"><img
src="http://img.geocaching.com/cache/17d8f38b-490d-45c2-a75f-8c67982591be.jpg"
width="50" height="50" alt="Wherigo Geocaching Tools (GC2C308)"
border="0" /></a> |
| Wherigo banner, poster size: |
 |
<a
href="http://www.wherigo.com/cartridge/details.aspx?CGUID=02168bb5-4c04-4a92-a8d5-f8d46dcf40c6"><img
src="http://img.geocaching.com/cache/4ecfbf97-04dc-4661-be2d-8295e0da4235.jpg"
width="120" height="150" alt="Wherigo Geocaching Tools" border="0"
/></a> |
| Wherigo banner, regular size: |
 |
<a
href="http://www.wherigo.com/cartridge/details.aspx?CGUID=02168bb5-4c04-4a92-a8d5-f8d46dcf40c6"><img
src="http://img.geocaching.com/cache/719c478a-c30f-49c0-a61a-10ec96291b09.jpg"
width="133" height="50" alt="Wherigo Geocaching Tools" border="0"
/></a> |
| Wherigo banner, small size: |
 |
<a
href="http://www.wherigo.com/cartridge/details.aspx?CGUID=02168bb5-4c04-4a92-a8d5-f8d46dcf40c6"><img
src="http://img.geocaching.com/cache/be8d36db-8986-4580-abbf-22887bfe2a70.jpg"
width="50" height="50" alt="Wherigo Geocaching Tools (GC2C308)"
border="0" /></a> |
Awards
I'm proud to have been awarded with: |
GeoCheck
You can check your solution with GeoCheck: |
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