likeliHUD

• Index

Contents

• Functions

Modules

• Utils

Classes

• Block
• Layout
• Rectangle
• Image
• Stack
• Label
• ImageButton
• TextField

Topics

• README

Examples

• buttons.lua
• elide.lua
• events.lua
• fill.lua
• focus.lua
• inside.lua
• layout.lua
• o.lua
• simple.lua
• squares.lua
• start.lua

Module Utils

Different utility functions

Functions

utils.round (x)	Round function.
utils.inside (x0, y0, x, y, w, h)	Tells whether or not a given point lies inside an axis-aligned rectangle.
utils.clearArray (t)	Clears the array part of the table.
utils.clear (t)	Clears the table.
utils.textAtWidth (text, width, font)	Returns the maximum substring (prefix) of a string which width is less than or equal to a given width.
utils.elide (text, width, font)	Elides the text and appends an ellipsis at the end if elided.
utils.placeAt (block, x, y, w, h, s)	Places the block in a given enclosing cell with some default algorithm.
utils.FSM (t)	Creates a finite state machine.

Functions

utils.round (x)

Round function.

Parameters:

• x A number.

Returns:

math.floor(x + 0.5)

utils.inside (x0, y0, x, y, w, h)

Tells whether or not a given point lies inside an axis-aligned rectangle.

Parameters:

• x0 The point's x-coordinate.
• y0 The point's y-coordinate.
• x x-coordinate of the top-left corner of the rectangle.
• y y-coordinate of the top-left corner of the rectangle.
• w Width of the rectangle.
• h Height of the rectangle.

Returns:

Whether the point (x0, y0) lies inside the rectangle (x, y, w, h).

utils.clearArray (t)

Clears the array part of the table.

Parameters:

• t A table.

utils.clear (t)

Clears the table.

Parameters:

• t A table.

utils.textAtWidth (text, width, font)

Returns the maximum substring (prefix) of a string which width is less than or equal to a given width. NOTE: this function will work only for fonts with monotonically increasing width once the length of the string increases. In other words, for any non-empty strings S1, S2: width(S1 + S2) > width(S1).

Parameters:

• text A string. The original text to elide.
• width A non-negative number. The width to fit the text.
• font A font. The target font.

Returns:

A string. The maximum prefix of text which width (according to the font font) is less or equal to width. If text is an empty string returns an empty string. If width is 0 returns an empty string.

utils.elide (text, width, font)

Elides the text and appends an ellipsis at the end if elided.

Parameters:

• text a string. The original text to elide.
• width a non-negative number. The width to fit the text.
• font a font. The target font.

See also:

utils.textAtWidth

Usage:

local t = 'Something went wrong' -- suppose this text is 10 units wide in out font
t = utils.elide(t, 4, font)
print(t) --> Somet...

utils.placeAt (block, x, y, w, h, s)

Places the block in a given enclosing cell with some default algorithm. It is unlikely you need this function ever -- it is used internally, but exposed for the sake of reusability.

Parameters:

• block a block. The block to place.
• x x coordinate of the enclosing cell.
• y y coordinate of the enclosing cell.
• w width of the enclosing cell.
• h height of the enclosing cell.
• s size of the block which must be used during placement. If nil then Block:size is used.

See also:

Block:place

utils.FSM (t)

Creates a finite state machine.

Parameters:

• t

  A table containing events, states and transitions.

  • events : an array of event IDs. Technically can be of any type that is allowed for a table key, but it is more convenient to use strings.

  • states : an array of state IDs. Technically can be of any type that is allowed for a table key, but it is more convenient to use strings.

  • transitions : a table of the following form.

    transitions = {
        eventID = {
            stateID_from = { state = stateID_to, action = f },
            stateID_from = { state = stateID_to, action = f },
            ...
        },
        eventID = {
            stateID_from = { state = stateID_to, action = f },
        },
        ...
    
        initial = stateID,
    }
    

    where eventID denotes the event that causes the transition, stateID_from and stateID_to is the current and the next state respectively, and action is a function that is called each time this transition is active. Also it must contain the initial state under the initial key. Events are processed via the process method: fsm:process(event). Below you can see an FSM which is used for managing mouse events in this library (which diagram can be seen in the Block:new section):

Usage:

local m = self.mouse

utils.FSM {
    events = {
        'press',
        'inside',
        'outside',
        'release',
    },

    states = {
        'idle',
        'hovered',
        'pressed'
    },

    transitions = {
        ['press']   = {
            ['hovered'] = { state = 'pressed', action = f(m.onPress) }
        },
        ['inside']  = {
            ['idle']    = { state = 'hovered', action = f(m.onEnter) }
        },
        ['outside'] = {
            ['pressed'] = { state = 'idle', action = f(m.onExit) },
            ['hovered'] = { state = 'idle', action = f(m.onExit) },
        },
        ['release'] = {
            ['pressed'] = { state = 'hovered', action = f(m.onClick) }
        },
    },

    initial = 'idle'
}