How can I make a fade out button?

Csound Noobs
1

Hi everyone
I need to make a button that when I press it, makes a fade out to the signal I’m playing.
Thank you

2

You could use the latched() property of the button and check when status of it is triggered. In case it is triggered, then call a line opcode…

3

You could also do something like this with a global variable.

form caption("Untitled") size(400, 300), colour(58, 110, 182), pluginID("def1")
button bounds(10, 10, 120, 40), text("Fade Out", "Fade In"), channel("fadeOut")
</Cabbage>
<CsoundSynthesizer>
<CsOptions>
-n -d -+rtmidi=NULL -M0 -m0d 
</CsOptions>
<CsInstruments>
; Initialize the global variables. 
sr = 44100
ksmps = 32
nchnls = 2
0dbfs = 1

gkFade init 1

instr 1
    kButton chnget "fadeOut"
    kTrig changed kButton
    if kTrig == 1 then
        if kButton == 1 then
            event "i", "APPLY_FADE", 0, 1, 0 ;pass 0 as p4 to fade down
        else
            event "i", "APPLY_FADE", 0, 1, 1 ;pass 1 as p4 to fade down
        endif
    endif

    a1 oscili gkFade, 200
    outs a1, a1
endin

instr APPLY_FADE
    if p4 == 1 then
        gkFade line 0, p3, 1
    else
        gkFade line 1, p3, 0
    endif
endin

</CsInstruments>
<CsScore>
;causes Csound to run for about 7000 years...
f0 z
;starts instrument 1 and runs it for a week
i1 0 [60*60*24*7] 
</CsScore>
</CsoundSynthesizer>

Btw, I believe there is a simple opcode that can triggering simple fade in/out envelopes, but I can never find it when I search for it. Anyone remember what it’s called?

2 Likes
4

Linsegr has a release segment

5

There was another opcode though I came across to would be perfect for this kind of thing. I’ll have another look. Each time I come across it I always think how perfect it would be for this kind of thing!

6

Or one could do this:

instr 1
    kButton chnget "fadeOut"
    kFade port kButton, 1
    a1 oscili kFade, 500
    outs a1, a1
endin

Still not the opcode I am trying to remember, but quite eloquent all the same.

7

@rorywalsh has been quicker.
Here is also a solution using the lineto opcode

<Cabbage>
form caption("Untitled") size(400, 300), colour(58, 110, 182), pluginID("def1")
keyboard bounds(8, 158, 381, 95)
button bounds(190, 32, 80, 40) channel("buttonchan3") text("Fade", "Rise") 
</Cabbage>
<CsoundSynthesizer>
<CsOptions>
-n -d -+rtmidi=NULL -M0 -m0d --midi-key-cps=4 --midi-velocity-amp=5
</CsOptions>
<CsInstruments>
; Initialize the global variables. 
sr = 44100
ksmps = 32
nchnls = 2
0dbfs = 1

gkFlag init  0

; This instrument manages the interface
instr 2
 if changed:k(chnget:k("buttonchan3"))==1 then
    if chnget:k("buttonchan3")==1 then
        gkFlag =0
    else 
        gkFlag = 1
    endif 
 endif
endin

;instrument will be triggered by keyboard widget
instr 1
kEnv madsr .1, .2, .6, .4
aOut vco2 p5, p4

kFade lineto gkFlag,1
aOut = aOut*kEnv*kFade
outs aOut, aOut
endin

</CsInstruments>
<CsScore>
;causes Csound to run for about 7000 years...
f0 z
i 2 0 z
</CsScore>
</CsoundSynthesizer>
1 Like
8

Thank you so much! This was very useful!