(Repost from my corresponding GitHub page. There may be differences between the two pages in the future.)

This page discusses my findings on the curly brace format used to display results of Funky Trees in labels. My research is based on a discussion, found on a Discord channel, about features used on labels on the main displays on the Wasp. This article aims to explain the workings of this format.

Funky Trees value substitution terms can follow the form {VALUE;FORMAT;UNITS}, where:

• VALUE is the Funky Trees, same as the kind used in variables and Input Controllers,
• FORMAT is a format specifier for the numeric value, and
• UNITS converts the displayed value by a game-defined factor and appends the unit to the numeric value.

The FORMAT and UNITS terms can only be applied to Funky Trees with numeric results. Boolean results will be converted into the numeric values -1 or 1 before any unit conversions, if applicable. String results will not work at all.

As the terms are used one after the other, using any term requires defining all previous terms. It is only possible to specify a unit conversion if the format is specified.

Label Format

The format specifier is defined in the System.NumberFormatter class, likely this implementation in Mono. Two styles of formats are allowed:

• Standard numeric format strings
• Custom numeric format strings

The following standard format specifiers do not work in SimplePlanes:

• Binary (B)
• Decimal (D)
• Hexadecimal (X)

However, the decimal format can be defined as a custom format by writing the desired number of zeroes. For example, the custom format 000 can be used in place of the standard format D3.

It is also possible to insert literal characters into custom numeric format strings. Rich text formatting defined inside the format string will work as normal. Such formatting can be used to create different styles for the value and its units, or to hide the units.

Lastly, to display only the associated unit without the numeric value or any other characters, the format ', '', ", or "" can be used.

Label Units

By defining a unit type for the label, the value in the label can automatically be converted from the units used internally by the game. The unit can be chosen from one of several categories, and will be converted from game units into the corresponding unit in the player's chosen unit system. The abbreviation of the unit will be inserted directly after the number with no separating spaces.

The following table lists the values allowed on the left, and the units that are available. The names of the units in the imperial, metric, and nautical systems are written as they are inserted in the labels. This data is available in Settings.xml, which is found in the SimplePlanes persistent data directory.

Label Unit Type Game Units  Imperial    Metric      Nautical
LongDistance    m       mi      km      nm
ShortDistance   m       ft      m       ft
TinyDistance    m       in      mm      in
Speed       m/s     mph     km/h        kts
Mass        kg      lbs     kg      lbs
Force       N       lbf     N       lbf
Volume      L       gal     L       gal
Area        m^2     ft^2        m^2     ft^2
WingLoading     kg/m^2      lbs/ft^2    kg/m^2      lbs/ft^2

As values from Funky Trees are converted to the unit system selected by the player, it removes the need to multiply by a conversion factor, and can improve usability for other players. However, the builder must be careful of any formatting issues that can be caused by the use of different units. The builder must also consider if the use of certain units is appropriate for the theme of the aircraft.

Examples

Simple Heading Display

{floor(repeat(Heading,360));000}

Displays heading as a three-digit integer from 000 to 359.

Wasp Altitude Display

<size=70%>ALT<size=100%><mspace=.5em><br><smallcaps>{Altitude;000000'<size=60%></mspace>';ShortDistance}

The label displays altitude as a six-digit integer, and the units are converted from meters to feet if the player has selected the imperial or nautical unit systems. In addition, the text within the single quotes ' are treated as literal characters that are inserted between the number and its unit.