Number Unit Descriptor Utilities [Widget Library]

Classes
struct	unit_t
Functions
double	to_base_value (double scaled_value, const unit_t &unit)
double	to_pinned_base_value (double scaled_value, const unit_t &unit, double min, double max)
double	to_scaled_value (double base_value, const unit_t &unit)
unit_t	to_unit (const dictionary_t &dict, const unit_t &default_unit=unit_t())

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Function Documentation

double adobe::to_base_value	(	double	scaled_value,
		const unit_t &	unit
	)

Performs an inverse-linear transformation on a scaled value given a unit.

Parameters:

scaled_value	is the value to be converted to the base value
unit	is the unit by which the scaled value is to be transformed

Returns:

the base value according to the unit_t's linear transformation.

Definition at line 189 of file number_unit.hpp.

double adobe::to_pinned_base_value	(	double	scaled_value,
		const unit_t &	unit,
		double	min,
		double	max
	)

Performs an inverse-linear transformation on a scaled value given a unit. It will also pin the value after the transformation has taken place to the unit_t's specified minimum and maximum values.

Todo:

the min and max values should come from the unit_t instead of parameters.

Parameters:

scaled_value	is the value to be converted to the base value
unit	is the unit by which the scaled value is to be transformed
min	is the minimum value allowed for the result
max	is the maximumn value allowed for the result

Returns:

the pinned base value according to the unit_t's linear transformation.

Definition at line 208 of file number_unit.hpp.

double adobe::to_scaled_value	(	double	base_value,
		const unit_t &	unit
	)

Performs a linear transformation on a base value given a unit.

Parameters:

base_value	is the value to be converted to the scaled value
unit	is the unit by which the base value is to be transformed

Returns:

the scaled value according to the unit_t's linear transformation.

Definition at line 176 of file number_unit.hpp.

unit_t adobe::to_unit	(	const dictionary_t &	dict,
		const unit_t &	default_unit = unit_t()
	)

Parameters:

dict	is the dictionary holding relevant unit information within.
default_unit	contains values for the resultant unit should they not be defined in dict.

Returns:

a complete unit_t as a result of the merging of the two parameters.

Dictionary Values

The values extracted from the dictionary are the following:

key	value type	default value	description
name	string	""	Name of this unit
bind	name	empty	Name of base unit to which this unit is bound
format	string	"#.00"	printf-style format for the widget when this unit is selected
increment	double	1	amount by which the property model value should be increemented when this unit is selected
scale	array of two doubles	[ 1.0, 0.0 ]	Scale factor for the property model's value to this specified unit. This allows you to represent a given cell (say, @width_inches) in an arbitrary unit given a linear conversion. The linear formula is y = a(x) + b, so the default settings are simply y = x. As an example, if you cell is saving values in unit inches and you want to display your value in centimeters, the scale would be [ 2.54, 0.0 ].
min_value	double	N/A	Optional. Minimum value allowed for this unit. Note that if you have a value that can be represented as multiple units, you have to specify a minimum value for each unit.
max_value	double	N/A	Optional. Maximum value allowed for this unit. Note that if you have a value that can be represented as multiple units, you have to specify a maximum value for each unit.