portamento.csd -odac -dm0 -M0 -+rtmidi=virtual sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; FLcolor 255, 255, 255, 0, 0, 0 ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "Portamento", 500, 170, 0, 0 ;VALUE DISPLAY BOXES WIDTH | HEIGHT | X | Y idporttime FLvalue " ", 60, 18, 5, 95 idcurve FLvalue " ", 60, 18, 5, 145 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkporttime,ihporttime FLslider "Portamento Time", 0, 1, 0, 23, idporttime, 490, 25, 5, 70 gkcurve,ihcurve FLslider "Curve (s-curve)", -8, 8, 0, 23, idcurve, 490, 25, 5,120 ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 4, 1, 255, 255, 255 ;LABELS MADE INVISIBLE (I.E. SAME COLOR AS PANEL) ;BUTTON BANKS TYPE | NUMX | NUMY | WIDTH | HEIGHT | X | Y | OPCODE gktype, ihtype FLbutBank 14, 1, 4, 18, 60, 50, 2, -1 ;GENERAL_TEXT_SETTINGS SIZE | FONT | ALIGN | RED | GREEN | BLUE FLlabel 13, 4, 3, 0, 0, 0 ;LABELS MADE VISIBLE AGAIN ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox "Type:", 1, 2, 14, 48, 15, 0, 0 ih FLbox "portk ", 1, 5, 12, 65, 15, 70, 0 ih FLbox "lineto ", 1, 5, 12, 65, 15, 70, 15 ih FLbox "s-curve 1", 1, 5, 12, 65, 15, 70, 30 ih FLbox "s-curve 2", 1, 5, 12, 65, 15, 70, 45 ;SET INITIAL VALUES VALUE | HANDLE FLsetVal_i 0.1, ihporttime FLsetVal_i 2, ihcurve FLsetVal_i 0, ihtype FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 515, 420, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " Portamento ", 1, 5, 14, 490, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 20, 5, 20 ih FLbox "Demonstration of three different approaches to implement ", 1, 5, 14, 490, 20, 5, 40 ih FLbox "pitch portamento between successive midi notes. ", 1, 5, 14, 490, 20, 5, 60 ih FLbox "The first method uses 'portk' which is really just a low pass", 1, 5, 14, 490, 20, 5, 80 ih FLbox "filter on the change of note. Changes between notes spaced ", 1, 5, 14, 490, 20, 5, 100 ih FLbox "far apart will take longer than changes between notes that ", 1, 5, 14, 490, 20, 5, 120 ih FLbox "are close together. ", 1, 5, 14, 490, 20, 5, 140 ih FLbox "The second method employs the 'lineto' opcode. This creates a", 1, 5, 14, 490, 20, 5, 160 ih FLbox "linear glide between the two notes and is the method that ", 1, 5, 14, 490, 20, 5, 180 ih FLbox "would be used on hardware synthesizers. Again glides between ", 1, 5, 14, 490, 20, 5, 200 ih FLbox "far apart notes will take longer than glides between notes ", 1, 5, 14, 490, 20, 5, 220 ih FLbox "that are close together. ", 1, 5, 14, 490, 20, 5, 240 ih FLbox "A third method (s-curve 1) moves between the two notes in the", 1, 5, 14, 490, 20, 5, 260 ih FLbox "shape of an inflected spline. The portamento time is the same", 1, 5, 14, 490, 20, 5, 280 ih FLbox "regardless of distance between the two notes. The shape of ", 1, 5, 14, 490, 20, 5, 300 ih FLbox "the curve (should be positive) can be set by the user. ", 1, 5, 14, 490, 20, 5, 320 ih FLbox "A fourth method (s-curve 2) differs to spline 1 in that ", 1, 5, 14, 490, 20, 5, 340 ih FLbox "portamento time is proportional to the gap between the old ", 1, 5, 14, 490, 20, 5, 360 ih FLbox "and new notes; rate of pitch change is constant. This method ", 1, 5, 14, 490, 20, 5, 380 ih FLbox "probably gives the most natural portamento effect. ", 1, 5, 14, 490, 20, 5, 400 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; opcode sspline,k,Kiii kdur,istart,iend,icurve xin ;READ IN INPUT ARGUMENTS imid = istart+((iend-istart)/2) ;SPLINE MID POINT VALUE isspline ftgentmp 0,0,4096,-16,istart,4096*0.5,icurve,imid,(4096/2)-1,-icurve,iend ;GENERATE 'S' SPLINE kspd = i(kdur)/kdur ;POINTER SPEED AS A RATIO (WITH REFERENCE TO THE ORIGINAL DURATION) kptr init 0 ;POINTER INITIAL VALUE kout tablei kptr,isspline ;READ VALUE FROM TABLE kptr limit kptr+((ftlen(isspline)/(i(kdur)*kr))*kspd), 0, ftlen(isspline)-1 ;INCREMENT THE POINTER BY THE REQUIRED NUMBER OF TABLE POINTS IN ONE CONTROL CYCLE AND LIMIT IT BETWEEN FIRST AND LAST TABLE POINT - FINAL VALUE WILL BE HELD IF POINTER ATTEMPTS TO EXCEED TABLE DURATION xout kout ;SEND VALUE BACK TO CALLER INSTRUMENT endop instr 1 ;NOTE ON/OFF AND PITCH REGISERING INSTRUMENT. THIS INSTRUMENT WILL BE TRIGGERED BY NOTE PLAYED ON THE MIDI KEYBOARD inum notnum ;READ IN MIDI NOTE NUMBERS gknum = inum ;CREATE A K-RATE GLOBAL VARIABLE VERSION OF MIDI PITCH THAT WILL BE USED IN INSTRUMENT 2. iInstr = 2 iactive active iInstr if iactive=0 then ; p4 event_i "i",iInstr,0,-1,p1 ;THE VERY FIRST MIDI NOTE PLAYED WILL TRIGGER AN INFINITELY HELD NOTE IN INSTR 2. THE maxalloc SETTING IN THE ORCHESTRA HEADER WILL PREVENT ANY FURTHER TRIGGERINGS. endif endin instr 2 ;SOUND PRODUCING INSTRUMENT kactive active p4 ;CONTINUALLY TRACK THE NUMBER OF ACTIVE INSTANCES OF INSTRUMENT 1. I.E. THE NUMBER OF MIDI NOTES HELD. if kactive==0 then turnoff endif kporttime linseg 0,0.001,1 ;RAMPING UP PORTAMENTO FUNCTION TO PREVENT PORTAMENTO FROM ZERO WITH FIRST NOTE if i(gktype)==0 then ;IF PORTK SELECTED... knum portk gknum,kporttime*gkporttime ;...APPLY PORTAMENTO SMOOTHING elseif i(gktype)==1 then ;OR IF LINETO IS SELECTED... knum lineto gknum,kporttime*gkporttime ;...APPLY LINETO SMOOTHING elseif i(gktype)==2 then ;OR IF S-CURVE TYPE 1 IS SELECTED... ktrig changed gknum ;...GENERATE A TRIGGER IS A NEW NOTE NUMBER IS GENERATED (FROM INSTR. 1) gkOldNum init i(gknum) ;OLD NOTE NUMBER = FIRST NOTE NUMBER UPON INITIAL NOTE BEING PLAYED if ktrig=1 then ;IF A NEW (LEGATO) NOTE HAS BEEN PRESSED reinit S_CURVE_1 ;BEGIN A REINITIALISATION PASS FROM LABEL endif ;END OF CONDITIONAL BRANCH S_CURVE_1: ;A LABEL. REINITIALISATION BEGINS FROM HERE. knum sspline gkporttime,i(gkOldNum),i(gknum),i(gkcurve) ;CALL sspline UDO rireturn ;RETURN FROM REINITIALISATION PASS gkOldNum = knum ;SET OLD NUMBER CURRENT NUMBER elseif i(gktype)==3 then ;...OR IF S-CURVE TYPE 2 IS SELECTED... ktrig changed gknum ;...GENERATE A TRIGGER IS A NEW NOTE NUMBER IS GENERATED (FROM INSTR. 1) gkOldNum init i(gknum) ;OLD NOTE NUMBER = FIRST NOTE NUMBER UPON INITIAL NOTE BEING PLAYED if ktrig=1 then ;IF A NEW (LEGATO) NOTE HAS BEEN PRESSED reinit S_CURVE_2 ;BEGIN A REINITIALISATION PASS FROM LABEL endif ;END OF CONDITIONAL BRANCH S_CURVE_2: ;A LABEL. REINITIALISATION BEGINS FROM HERE. idiff = 1+abs(i(gknum)-i(gkOldNum)) ;ABSOLUTE DIFFERENCE BETWEEN OLD NOTE AND NEW NOTE IN STEPS (+ 1) knum sspline gkporttime*idiff,i(gkOldNum),i(gknum),i(gkcurve);CALL sspline UDO (PORTASMENTO TIME MULTIPLIED BY NOTE GAP (idiff)) rireturn ;RETURN FROM INITIALISATION PASS gkOldNum = knum ;SET OLD NUMBER CURRENT NUMBER endif ;END OF CONDITIONAL BRANCH ;CREATE A SAWTOOTH OSCILLATOR USING THE vco2 OPCODE asig vco2 0.3,cpsmidinn(knum),4,0.5 ;AUDIO OSCILLATOR outs asig,asig ;SEND AUDIO TO OUTPUT endin f 0 360000 e