;Written by Iain McCurdy, 2006 -+rtaudio=PortAudio -b4096 sr = 44100 ;SAMPLE RATE kr = 441 ;CONTROL RATE ksmps = 100 ;NUMBER OF AUDIO SAMPLES IN EACH CONTROL CYCLE nchnls = 2 ;NUMBER OF CHANNELS (2=STEREO) ;FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; LABEL | WIDTH | HEIGHT | X | Y FLpanel "lowpass2", 500, 200, 0, 0 ;SWITCHES ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | DUR gkOnOff,ihOnOff FLbutton "On/Off", 1, -1, 2, 150, 30, 0, 0, 0, 2, 0, -1 ;VALUE DISPLAY BOXES LABEL | WIDTH | HEIGHT | X | Y idcf FLvalue " ", 100, 20, 0, 80 idq FLvalue " ", 100, 20, 0, 130 idamp FLvalue " ", 100, 20, 0, 180 ;COUNTERS MIN | MAX | STEP1 | STEP2 | TYPE | WIDTH | HEIGHT | X | Y | OPCODE gkskip, ihskip FLcount "Initialisation 0-On 1-Off", 0, 1, 1, 1, 2, 150, 30, 350, 0, -1 ;SLIDERS MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkcf,ihcf FLslider "Filter Cutoff", 20, 20000, -1, 5, idcf, 500, 30, 0, 50 gkq,ihq FLslider "Q (resonance)", 1, 500, -1, 5, idq, 500, 30, 0, 100 gkamp,ihamp FLslider "Output Amplitude Scaling", 0, 1, 0, 5, idamp, 500, 30, 0, 150 ;SET INITIAL VALUES OF FLTK VALUATORS ; VALUE | HANDLE FLsetVal_i 10000, ihcf FLsetVal_i 1, ihq FLsetVal_i -1, ihOnOff FLsetVal_i 1, ihamp FLsetVal_i 0, ihskip FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 500, 300, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " lowpass2 ", 1, 5, 14, 490, 15, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 15, 5, 20 ih FLbox "Lowpass2 is an implementation of a second-order resonant IIR ", 1, 5, 14, 490, 15, 5, 40 ih FLbox "low-pass filter. Its input arguments are for filter cutoff ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "frequency (in hertz), Q or resonance (a value in the range 1 ", 1, 5, 14, 490, 15, 5, 80 ih FLbox "to 500) and an optional 2-way switch (default=0) to select ", 1, 5, 14, 490, 15, 5, 100 ih FLbox "whether the data space for feedback within the filter is ", 1, 5, 14, 490, 15, 5, 120 ih FLbox "initially cleared or allowed to retain previously held ", 1, 5, 14, 490, 15, 5, 140 ih FLbox "information. ", 1, 5, 14, 490, 15, 5, 160 ih FLbox "Use of high levels of resonance can cause significant ", 1, 5, 14, 490, 15, 5, 180 ih FLbox "increases in the overall output amplitude. It may be desired ", 1, 5, 14, 490, 15, 5, 200 ih FLbox "to make use of the balance opcode to control these ", 1, 5, 14, 490, 15, 5, 220 ih FLbox "fluctuations in amplitude. Alternatively a control to scale ", 1, 5, 14, 490, 15, 5, 240 ih FLbox "the output amplitude can be implemented (as has been done in ", 1, 5, 14, 490, 15, 5, 260 ih FLbox "this example). ", 1, 5, 14, 490, 15, 5, 280 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 ;(ALWAYS ON - SEE SCORE) PLAYS FILE AND SENSES FADER MOVEMENT AND RESTARTS INSTR 2 FOR I-RATE CONTROLLERS ;OUTPUTS OPCODE FILE | SPEED | INSKIP | LOOPING (0=OFF 1=ON) gasigL, gasigR diskin "Seashore.wav", 1, 0, 1 ;GENERATE 2 AUDIO SIGNALS FROM A STEREO SOUND FILE (NOTE THE USE OF GLOBAL VARIABLES) kSwitch changed gkskip ;GENERATE A MOMENTARY '1' PULSE IN OUTPUT 'kSwitch' IF ANY OF THE SCANNED INPUT VARIABLES CHANGE. (OUTPUT 'kSwitch' IS NORMALLY ZERO) ; ITRIGGER | IMINTIM | IMAXNUM | IINSNUM | IWHEN | IDUR (-1 MEANS A NOTE OF INFINITE DURATION) schedkwhen kSwitch, 0, 0, 2, 0, -1 ;RESTART INSTRUMENT 2 WITH A SUSTAINED (HELD) NOTE WHENEVER kSwitch=1 endin instr 2 if gkOnOff!=-1 goto CONTINUE ;SENSE FLTK ON/OFF SWITCH turnoff ;TURN THIS INSTRUMENT OFF IMMEDIATELY CONTINUE: aresL lowpass2 gasigL, gkcf, gkq , i(gkskip) aresR lowpass2 gasigR, gkcf, gkq , i(gkskip) outs aresL * gkamp, aresR * gkamp ;SEND FILTER OUTPUT TO THE AUDIO OUTPUTS AND SCALE USING THE FLTK SLIDER VARIABLE gkamp endin ;INSTR | START | DURATION i 1 0 3600 ;INSTRUMENT 1 PLAYS FOR 1 HOUR