In order to use this API, you should be aware of a few basic rules in order to understand it:
* A HUD bar is an approximate graphical representation of the ratio of a current value and a maximum value, i.e. current health of 15 and maximum health of 20. A full HUD bar represents 100%, an empty HUD bar represents 0%.
* The current value must always be equal to or smaller then the maximum
* Both current value and maximum must not be smaller than 0
* Both current value and maximum must be real numbers. So no NaN, infinity, etc.
* The HUD bar will be hidden if the maximum equals 0. This is intentional.
*`identifier`: A globally unique internal name for the HUD bar, will be used later to refer to it. Please only rely on alphanumeric characters for now. The identifiers “`health`” and “`breath`” are used internally for the built-in health and breath bar, respectively. Please do not use these names.
*`text_color`: A 3-octet number defining the color of the text. The octets denote, in this order red, green and blue and range from `0x00` (complete lack of this component) to `0xFF` (full intensity of this component). Example: `0xFFFFFF` for white.
*`bar`: The file name of the bar image (as string). This is only used for the `progress_bar` bar type (see `README.txt`, settings section).
*`icon`: The file name of the icon, as string. For the `progress_bar` type, it is shown as single image left of the bar, for the two statbar bar types, it is used as the statbar icon and will be repeated. This field can be `nil`, in which case no icon will be used, but this is not recommended, because the HUD bar will be invisible if the one of the statbar bar types is used.
*`bgicon`: The file name of the background icon, it is used as the background for the modern statbar mode only. This field can be `nil`, in which case no background icon will be displayed in this mode.
*`default_start_value`: If this HUD bar is added to a player, and no initial value is specified, this value will be used as initial current value
*`default_max_value`: If this HUD bar is added to a player, and no initial maximum value is specified, this value will be used as initial maximum value
*`format_string`: Optional; You can specify an alternative format string to use for the final text on the HUD bar. The default format string is “`@1: @2/@3`” (The “@” numbers are placeholders that have a meaning in this order: @1 = Label, @2 = current value, @3 = maximum value). Do *not* use minetest.translator on this string, the string will be translated by `hudbars`, but you still must put this string into the translation catalogue file.
*`format_string_config`: Required if `format_string` is set. This allows to change which parameters to use in the format string. It's a table with these fields:
*`textdomain`: Text domain of the format string, used by `minetest.translate`
*`order`: Table that contains the order of the placeholders. It's also possible to remove placeholders. Default order: `{ "label", "value", "max_value" }`
Displays an armor HUD bar with a label of the form „Armor: 53%“. (`N` is a dummy function that returns its argument, used to make the string visible for translator scripts.)
*`start_value`: The initial current value of the HUD bar. This is optional, `default_start_value` of the registration function will be used, if this is `nil`.
*`start_max`: The initial maximum value of the HUD bar. This is optional, `default_start_max` of the registration function will be used, if this is `nil`
*`start_hidden`: Whether the HUD bar is initially hidden. This is optional, `default_start_hidden` of the registration function will be used as default
