This should play if your Web browser has WebAssembly enabled (most do). Most examples will play unless they need to load files. The first time you click Play, Csound will spend a few seconds loading, then play. You can edit this code and replay it.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac ;;;realtime audio ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o pindex-2.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Required settings for WebAudio: sr = 48000 ksmps = 128 nchnls = 2 nchnls_i = 1 ; sr = 44100 ; ksmps = 32 ; nchnls = 2 0dbfs = 1 ; This UDO returns a pfield value but returns 0 if it does not exist. opcode mypvalue, i, i index xin inum pcount if (index > inum) then iout = 0.0 else iout pindex index endif xout iout endop ; Envelope UDO that reads parameters from a flexible number of pfields ; Syntax: kenv flexlinseg ipstart ; ipstart is the first pfield of the envelope ; parameters. Reads remaining pfields (up to 21 of them). ; kenv is the output envelope. opcode flexlinseg, k, i ipstart xin iep1 mypvalue ipstart iep2 mypvalue ipstart + 1 iep3 mypvalue ipstart + 2 iep4 mypvalue ipstart + 3 iep5 mypvalue ipstart + 4 iep6 mypvalue ipstart + 5 iep7 mypvalue ipstart + 6 iep8 mypvalue ipstart + 7 iep9 mypvalue ipstart + 8 iepa mypvalue ipstart + 9 iepb mypvalue ipstart + 10 iepc mypvalue ipstart + 11 iepd mypvalue ipstart + 12 iepe mypvalue ipstart + 13 iepf mypvalue ipstart + 14 iepg mypvalue ipstart + 15 ieph mypvalue ipstart + 16 iepi mypvalue ipstart + 17 iepj mypvalue ipstart + 18 iepk mypvalue ipstart + 19 iepl mypvalue ipstart + 20 kenv linseg iep1, iep2, iep3, iep4, iep5, iep6, iep7, iep8, \ iep9, iepa, iepb, iepc, iepd, iepe, iepf, iepg, \ ieph, iepi, iepj, iepk, iepl xout kenv endop instr 1 ; This instrument only requires 3 pfields but can accept up to 24. ; (You will still get warnings about more than 3). kenv flexlinseg 4 ; envelope params start at p4 aout oscili kenv*.5, 256, 1 outs aout, aout endin </CsInstruments> <CsScore> f1 0 8192 10 1 i1 0 2 0.0 1.0 1.0 1.0 0.0 i1 2 2 0.0 0.1 1.0 1.0 1.0 0.1 0.0 i1 4 2 0.0 0.5 0.0 ; one problem is that "missing" pfields carry i1 6 2 0.0 0.5 0.0 ! ; now we can fix this problem with ! i1 8 10 0.0 3.0 1.0 0.3 0.1 0.3 1.0 0.3 0.1 0.3 1.0 0.3 0.1 0.8 0.9 5.0 0.0 e </CsScore> </CsoundSynthesizer>