;Written by Iain McCurdy, 2006 -+rtaudio=PortAudio -b4096 sr = 44100 kr = 4410 ksmps = 10 nchnls = 2 ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "vco", 500, 400, 0, 0 ;SWITCHES ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | IDUR gkOnOff,ihOnOff FLbutton "On/Off", 1, -1, 2, 150, 30, 0, 0, 0, 1, 0, 3600 ;VALUE DISPLAY BOXES WIDTH | HEIGHT | X | Y idamp FLvalue " ", 80, 20, 0, 125 idcps FLvalue " ", 80, 20, 0, 175 idleak FLvalue " ", 80, 20, 0, 225 idnyx FLvalue " ", 80, 20, 0, 275 idpw FLvalue " ", 80, 20, 0, 325 idphs FLvalue " ", 80, 20, 0, 375 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkamp, ihamp FLslider "Amplitude", 0, 32767, 0, 3, idamp, 500, 25, 0, 100 gkcps, ihcps FLslider "Frequency (Hertz)", 2, 10000, -1, 3, idcps, 500, 25, 0, 150 gkleak, ihleak FLslider "Integrator Leak", 0, 1, 0, 3, idleak, 500, 25, 0, 200 gknyx, ihnyx FLslider "Number of Harmonics", 20, sr/2, -1, 3, idnyx, 500, 25, 0, 250 gkpw, ihpw FLslider "Pulse Width", 0, 1, 0, 3, idpw, 500, 25, 0, 300 gkphs, ihphs FLslider "Initial Phase", 0, 1, 0, 3, idphs, 500, 25, 0, 350 ;COUNTERS MIN | MAX | STEP1 | STEP2 | TYPE | WIDTH | HEIGHT | X | Y | OPCODE gkwave,ihwave FLcount "Waveform", 1, 3, 1, 1, 2, 150, 30, 175, 0, -1 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox "1=Saw 2=Square/PWM 3=Saw/Triangle/Ramp", 1, 5, 12, 150, 15, 175, 55 ;SET INITIAL VALUES VALUE | HANDLE FLsetVal_i 10000, ihamp FLsetVal_i 100, ihcps FLsetVal_i 1, ihwave FLsetVal_i 0, ihleak FLsetVal_i sr/2, ihnyx FLsetVal_i .5, ihpw FLsetVal_i 0, ihphs FLpanel_end ;END OF PANEL CONTENTS ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 515, 700, 512, 0 FLscroll 515, 700, 0, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " Miscellaneous Waveforms : vco ", 1, 5, 14, 490, 15, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 15, 5, 20 ih FLbox "Vco is a digital emulation of a voltage controlled oscillator", 1, 5, 14, 490, 15, 5, 40 ih FLbox "that one might find on an analogue synthesizer. ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "The precise method used is the integration of band limited ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "impulses. Vco implements a digital model of the analogue ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "electronics that were used to achieve this. ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "It has three basic waveform settings: 'Saw', 'Square/PWM' and", 1, 5, 14, 490, 15, 5, 80 ih FLbox "'Saw/Triangle/Ramp'. As you can see, two of these settings ", 1, 5, 14, 490, 15, 5, 100 ih FLbox "are capable of producing more than one wave type. This is ", 1, 5, 14, 490, 15, 5, 120 ih FLbox "achieved by warping the waveform using the 'Pulse Width' (PW)", 1, 5, 14, 490, 15, 5, 140 ih FLbox "control. ", 1, 5, 14, 490, 15, 5, 160 ih FLbox "For example when the 'Square/PWM' waveform is selected a ", 1, 5, 14, 490, 15, 5, 180 ih FLbox "square wave is achieved by setting 'Pulse Width' to 0.5. When", 1, 5, 14, 490, 15, 5, 200 ih FLbox "'Saw/Triangle/Ramp' is selected a triangle wave is achieved ", 1, 5, 14, 490, 15, 5, 220 ih FLbox "by setting 'Pulse Width' again to 0.5. Giving 'Pulse Width' a", 1, 5, 14, 490, 15, 5, 240 ih FLbox "value of zero or 1 achieves silence. PWM or 'Pulse Width ", 1, 5, 14, 490, 15, 5, 260 ih FLbox "Modulation' was a an effect popular on analogue synthesizers ", 1, 5, 14, 490, 15, 5, 280 ih FLbox "whereby the pulse width of a waveform was modulated by an LFO", 1, 5, 14, 490, 15, 5, 300 ih FLbox "(Low Frequency Oscillator). In this example this can only be ", 1, 5, 14, 490, 15, 5, 320 ih FLbox "achieved by manually moving the 'Pulse Width' slider back and", 1, 5, 14, 490, 15, 5, 340 ih FLbox "forth. In the next example featuring vco an LFO has been ", 1, 5, 14, 490, 15, 5, 360 ih FLbox "implemented to drive the 'Pulse Width' parameter. Note that ", 1, 5, 14, 490, 15, 5, 380 ih FLbox "'Pulse Width' has no effect when 'Saw' waveform is selected. ", 1, 5, 14, 490, 15, 5, 400 ih FLbox "The 'Integrator Leak' control implements a quirk of the ", 1, 5, 14, 490, 15, 5, 420 ih FLbox "original analogue oscillator upon which this is based which ", 1, 5, 14, 490, 15, 5, 440 ih FLbox "has an effect on the sound produced. For a more in depth ", 1, 5, 14, 490, 15, 5, 460 ih FLbox "discussion I point you in the direction of the the Csound ", 1, 5, 14, 490, 15, 5, 480 ih FLbox "Reference Manual in which the opcode's author, Hans Mikelson,", 1, 5, 14, 490, 15, 5, 500 ih FLbox "gives more technical information about the effect of ", 1, 5, 14, 490, 15, 5, 520 ih FLbox "integrator leakage. ", 1, 5, 14, 490, 15, 5, 540 ih FLbox "'Number of Harmonics' can be used to limit the number of ", 1, 5, 14, 490, 15, 5, 560 ih FLbox "harmonics that will be present in the waveform. Normally this", 1, 5, 14, 490, 15, 5, 580 ih FLbox "argument should be in the range close to zero up to 0.5. I ", 1, 5, 14, 490, 15, 5, 600 ih FLbox "have done some additional mathematics in the code so that the", 1, 5, 14, 490, 15, 5, 620 ih FLbox "values you see in the interface represent this harmonic limit", 1, 5, 14, 490, 15, 5, 640 ih FLbox "in hertz. the author suggests that a waveform can be ", 1, 5, 14, 490, 15, 5, 660 ih FLbox "'fattened up' by reducing this parameter. ", 1, 5, 14, 490, 15, 5, 680 ih FLbox "Vco provides a useful source for subtractive synthesis and ", 1, 5, 14, 490, 15, 5, 700 ih FLbox "could be used as the starting point for a Csound model of an ", 1, 5, 14, 490, 15, 5, 720 ih FLbox "analogue synthesizer. ", 1, 5, 14, 490, 15, 5, 740 FLscrollEnd FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;(ALWAYS ON - SEE SCORE) SENSES FADER MOVEMENT kSwitch changed gkleak, gknyx, gkwave, gkphs ; ITRIGGER | IMINTIM | IMAXNUM | IINSNUM | IWHEN | IDUR (-1 MEANS A NOTE OF INFINITE DURATION) schedkwhen kSwitch, 0, 0, 2, 0, -1 endin instr 2 if gkOnOff!=-1 kgoto CONTINUE ;SENSE IF FLTK INSTRUMENT ON/OFF SWITCH IS NOT OFF (IN WHICH CASE SKIP THE NEXT LINE) turnoff ;TURN THIS INSTRUMENT OFF IMMEDIATELY CONTINUE: ;A LABEL iamp = 10000 ifn = 1 imaxd = 1 asig vco gkamp, gkcps, i(gkwave), gkpw, ifn, imaxd, i(gkleak), i(gknyx)/sr, i(gkphs) outs asig, asig endin f1 0 131072 10 1 ; audio function f 0 3600