yg.util

Utility classes.

class yg.util.Motion

Represents a scalar value that performs a sequence of motion segments over time.

Example

function init()
    -- Initialize a Motion object. Make a repeating Motion:
    --   Acting from -9 to 9 in 3 seconds with SMOOTH2 easing
    --   Idling 0.2 seconds at 9
    --   Moving back to -9 in 1.5 seconds with CUBEDOWN easing
    --   Idling 0.2 seconds at -9
    mot = yg.util.Motion("REPEAT")
    mot:addRamp(3.0, -9, 9, "SMOOTH2")
    mot:addIdle(0.2, 9)
    mot:addRamp(1.5, 9, -9, "CUBEDOWN")
    mot:addIdle(0.2, -9)
end

function tick()
    -- Tick the Motion with the time delta of the last frame
    mot:tick(yg.time.getDelta())

    -- Get the current scalar value of the Motion (and do something with it)
    motVal = mot:val()
end

constructor

yg.util.Motion(flowType) -> yg.util.Motion

Argument	Type	Info
flowType	string	Motion flow type. Options: "ONCE", "REPEAT", "PINGPONG"

function yg.util.Motion.addIdle()

Adds an idle segment to the Motion.

ToDo: check if chaining works and if this function returns a Motion reference.

yg.util.Motion.addIdle(dt, val) -> void

Argument	Type	Info
dt	number	Duration of the segment [seconds]
val	number	Constant (idle) value of the segment

function yg.util.Motion.addRamp()

Adds a ramp segment to the Motion.

ToDo: check if chaining works and if this function returns a Motion reference.

yg.util.Motion.addRamp(dt, val0, val1, ease) -> void

Argument	Type	Info
dt	number	Duration of the segment [seconds]
val0	number	Start value of the segment
val1	number	End value of the segment
ease	string	Easing of the segment. Options: "NONE", "SQUARE", "SQUAREDOWN", "CUBE", "CUBEDOWN", "SINE", "SINEDOWN", "SMOOTH", "SMOOTH2"

function yg.util.Motion.tick()

Advances (ticks) the motion by a given time delta.

yg.util.Motion.tick(dt) -> void

Argument	Type	Info
dt	number	Time delta [seconds]

function yg.util.Motion.val()

Returns the current scalar value of the motion.

yg.util.Motion.val() -> number

function yg.util.Motion.pause()

Enables/disables (pauses) the Motion. During pause, tick() has no effect.

yg.util.Motion.pause(pause) -> void

Argument	Type	Info
pause	boolean	Enable/disable pause. Options: true, false

function yg.util.Motion.restart()

Restarts the Motion.

yg.util.Motion.restart() -> void

function yg.util.Motion.setDirection()

Enables/disables forward direction of the Motion.

yg.util.Motion.setDirection(forward) -> void

Argument	Type	Info
forward	boolean	Enable/disable forward direction. Options: true, false

function yg.util.Motion.isFinished()

Returns true if the Motion is finished.

yg.util.Motion.isFinished() -> boolean

function yg.util.Motion.isPaused()

Returns true if the Motion is paused.

yg.util.Motion.isPaused() -> boolean

function yg.util.Motion.getDirection()

Returns true if the Motion is in forward direction.

yg.util.Motion.getDirection() -> boolean