GEN11.csd Written by Iain McCurdy, 2011 -odac --displays sr = 44100 ;SAMPLE RATE ksmps = 8 ;NUMBER OF AUDIO SAMPLES IN EACH CONTROL CYCLE nchnls = 1 ;NUMBER OF CHANNELS (1=MONO) 0dbfs = 1 ;MAXIMUM AMPLITUDE ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 0, 0, 0 ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "GEN11", 500, 170, 0, 0 ;SWITCHES ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | IDUR gkOnOff,ihOnOff FLbutton "Play Tone", 1, 0, 22, 120, 25, 5, 5, -1 gkSclFrq,ihSclFrq FLbutton "Rescale Frq.", 1, 0, 22, 120, 25, 5, 35, -1 FLsetColor2 255, 255, 50, ihOnOff ;SET SECONDARY COLOUR TO YELLOW FLsetColor2 255, 255, 50, ihSclFrq ;SET SECONDARY COLOUR TO YELLOW ;VALUE DISPLAY BOXES LABEL | WIDTH | HEIGHT | X | Y idfrq FLvalue " ", 50, 17, 130, 20 idamp FLvalue " ", 50, 17, 130, 55 idr FLvalue " ", 50, 17, 5, 145 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkfrq,ihfrq FLslider "Frequency", 1, 5000, -1, 23, idfrq, 360, 15, 130, 5 gkamp,ihamp FLslider "Global Amp.", 0, 1, 0, 23, idamp, 360, 15, 130, 40 gkr,ihr FLslider "Amp.Power", 0, 4, 0, 23, idr, 490, 25, 5, 120 ;COUNTERS MIN | MAX | STEP1 | STEP2 | TYPE | WIDTH | HEIGHT | X | Y | OPCODE gknh, ihnh FLcount "Num.Harms.", 1, 500, 1, 10, 1, 120, 25, 10, 75, -1 gklh, ihlh FLcount "Lowest Harm.", 1, 500, 1, 10, 1, 120, 25, 135, 75, -1 ;SET INITIAL VALUES OF FLTK VALUATORS VALUE | HANDLE FLsetVal_i 440, ihfrq FLsetVal_i 0.3, ihamp FLsetVal_i 1, ihr FLsetVal_i 8, ihnh FLsetVal_i 1, ihlh FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 500, 600, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " GEN11 ", 1, 5, 14, 490, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "GEN11 is a function table version of the 'gbuzz' opcode. ", 1, 5, 14, 490, 20, 5, 40 ih FLbox "The waveform GEN11 creates is a composite of harmonically ", 1, 5, 14, 490, 20, 5, 60 ih FLbox "related cosine waves. The user can specify the number of ", 1, 5, 14, 490, 20, 5, 80 ih FLbox "cosine waves in the stack and the partial number of the ", 1, 5, 14, 490, 20, 5, 100 ih FLbox "lowest cosine in the stack. Finally, just as with gbuzz, a ", 1, 5, 14, 490, 20, 5, 120 ih FLbox "multipler in an amplitude coefficient series is provided. ", 1, 5, 14, 490, 20, 5, 140 ih FLbox "Varying this parameter will shift the spectral predominence ", 1, 5, 14, 490, 20, 5, 160 ih FLbox "up or down the stack of partials. ", 1, 5, 14, 490, 20, 5, 180 ih FLbox "An efficiency advantage of using GEN11 over gbuzz is that ", 1, 5, 14, 490, 20, 5, 200 ih FLbox "calculation of the waveform can be done at the start of ", 1, 5, 14, 490, 20, 5, 220 ih FLbox "Csound performance once only as opposed to with every note, ", 1, 5, 14, 490, 20, 5, 240 ih FLbox "as would be the case when using gbuzz. In this implementation", 1, 5, 14, 490, 20, 5, 260 ih FLbox "because the function table is being forced to reintialise ", 1, 5, 14, 490, 20, 5, 280 ih FLbox "whenever changes are made, the table has to be recalculated ", 1, 5, 14, 490, 20, 5, 300 ih FLbox "anyway. The advantage to using gbuzz over GEN11 is that its ", 1, 5, 14, 490, 20, 5, 320 ih FLbox "parameters can be modulated at k-rate. The parameter ", 1, 5, 14, 490, 20, 5, 340 ih FLbox "modulation implemented in this example is not k-rate ", 1, 5, 14, 490, 20, 5, 360 ih FLbox "modulation and may produce discontinuities in the output. ", 1, 5, 14, 490, 20, 5, 380 ih FLbox "Changes made to the function table can be viewed in the ", 1, 5, 14, 490, 20, 5, 400 ih FLbox "output waveform if displays are enabled (i.e. if the -d flag ", 1, 5, 14, 490, 20, 5, 420 ih FLbox "is not used). ", 1, 5, 14, 490, 20, 5, 440 ih FLbox "If the 'Rescale Frq.' button is activated then the ", 1, 5, 14, 490, 20, 5, 460 ih FLbox "fundemental of the audio generating oscillator is rescaled ", 1, 5, 14, 490, 20, 5, 480 ih FLbox "by the reciprocal of the lowest harmonic - the frequency of ", 1, 5, 14, 490, 20, 5, 500 ih FLbox "the lowest harmonic will in this case correspond to the ", 1, 5, 14, 490, 20, 5, 520 ih FLbox "frequency defined by the 'Frequency' slider. For example: if ", 1, 5, 14, 490, 20, 5, 540 ih FLbox "'Lowest Harm' is '1', no rescaling is applied, if it is '2', ", 1, 5, 14, 490, 20, 5, 560 ih FLbox "frequency of the oscillator is divided by 2. ", 1, 5, 14, 490, 20, 5, 580 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;UPDATES FUNCTION TABLE ktrig changed gknh,gklh,gkr ;SENSE IF ONE OF THE PARAMETERS FOR CREATING THE FUNCTION TABLE HAS BEEN CHANGED, OUTPUT A MOMENTARY 1 IF ONE HAS if ktrig=1 then ;IF A PARAMETER FOR THE FUNCTION TABLE HAS BEEN CHANGED... reinit UPDATE ;...BEGIN A REINITIALISATION PASS FROM LABEL 'UPDATE' IN ORDER TO CREATE THE FUNCTION TABLE. (THIS CANNOT BE DONE AT PERFORMANCE TIME) UPDATE: ;A LABEL. BEGIN REINITIALIZATION FROM HERE. ;CREATE THE GEN09 FUNCTION TABLE. ;FUNCTION TABLE NUMBER IS DEFINED EXPLICITLY (I.E. NOT ZERO) SO THAT THE OLD TABLE WILL BE OVER-WRITTEN EACH TIME A CHANGE IS MADE giwave ftgen 1,0,4096,11,i(gknh),i(gklh),i(gkr) rireturn ;RETURN FROM REINITIALIZATION PASS endif ;END OF THIS CONDITIONAL BRANCH if gkOnOff=1 then ;IF ON/OFF BUTTON IS ON... kporttime linseg 0,0.001,0.01 ;CREATE A FUNCTION THAT RISES QUICKLY TO A HELD VALUE THAT WILL BE USED FOR PORTAMENTO TIME kfrq portk gkfrq,kporttime ;APPLY PORTAMENTO SMOOTHING TO THE FLTK SLIDER VARIABLE kamp portk gkamp,kporttime ;APPLY PORTAMENTO SMOOTHING TO THE FLTK SLIDER VARIABLE if gkSclFrq==1 then ;IF RESCALING FREQUENCY BUTTON IS ACTIVATED... kfrq=kfrq/gklh ;DIVIDE BASE FREQUENCY BY THE PARTIAL NUMBER OF THE LOWEST PARTIAL endif ;END OF THIS CONDITIONAL BRANCH a1 oscili kamp,kfrq,giwave ;CREATE AN LINEARLY INTERPOLATING AUDIO OSCILLATOR THAT WILL USE THE GEN09 DESIGNED WAVEFORM out a1 ;SEND THE AUDIO TO THE OUTPUT. APPLY THE AMPLITUDE ENVELOPE endif endin instr 2 ;PLAYS A TONE endin i 1 0 3600 ;INSTRUMENT 1 PLAYS A NOTE FOR 1 HOUR (AND KEEPS PERFORMANCE GOING)