sfx - nesbox/TIC-80 GitHub Wiki
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()
cls()
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