sfx

sfx(id, [note=-1], [duration=-1], [channel=0], [volume=15], [speed=0])

...or to stop playing:

sfx(-1)
sfx(-1, nil, nil, channel)

Parameters

• id : the SFX id (0..63) or -1 to stop playing
• note : the note number or name (see below) or -1 to play the last note note assigned in the SFX Editor
• duration : the duration (number of frames) or -1 to play continuously
• channel : the audio channel to use (0..3)
• volume : the volume (0..15)
• speed : the speed (-4..3)

Description

This function will play the sound with id created in the SFX Editor. Calling the function with an id of -1 will stop playing a channel: sfx(-1) stops the default channel (0), sfx(-1, nil, nil, n) stops playing channel 'n'.

The note can be supplied as an integer between 0 and 95 (representing 8 octaves of 12 notes each) or as a string giving the note name and octave. For example, a note value of '14' will play the note 'D' in the second octave. The same note could be specified by the string 'D-2'. Note names consist of two characters, the note itself (in upper case) followed by '-' to represent the natural note or '#' to represent a sharp. There is no option to indicate flat values. The available note names are therefore: C-, C#, D-, D#, E-, F-, F#, G-, G#, A-, A#, B-. The octave is specified using a single digit in the range 0 to 8.

The duration specifies how many ticks to play the sound for; since TIC-80 runs at 60 frames per second, a value of 30 represents half a second. A value of -1 will play the sound continuously.

The channel parameter indicates which of the four channels (0 to 3) to use.

Volume can be set within the range 0 to 15.

Speed in the range -4 to 3 specifies the speed at which the SFX envelope is traversed and corresponds with the speed setting in the SFX Editor.

Example

-- title:  sfx example
-- author: paul59
-- script: lua

local t=0
function TIC()
	t=t+1
	-- play note 14 (D in octave 2)
	-- every half second with a duration of 
	-- 20 ticks
	if t%30==0 then sfx(0,14,20) end
	-- play D in octave 4 every second
	-- with a duration of 20 ticks
	-- use channel 1 and volume 10
	if t%60==0 then sfx(0,'D-4',20,1,10) end
	-- every 2 seconds
	-- play D quietly in octave 5
	if t%120==0 then sfx(0,'D-5',20,1,4) end
end