;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 "FM Synthesis: Simple Carrier->Modulator", 500, 300, 0, 0 ; ON | OFF | TYPE | WIDTH | HEIGHT | X | Y | OPCODE | INS | STARTTIM | IDUR gkOnOff,ihOnOff FLbutton "On/Off", 1, -1, 2, 150, 28, 0, 0, 0, 1, 0, 3600 ;VALUE DISPLAY BOXES WIDTH | HEIGHT | X | Y idbasefreq FLvalue " ", 60, 20, 0, 80 idindex FLvalue " ", 60, 20, 0, 130 idCarAmp FLvalue " ", 60, 20, 0, 280 ; MIN | MAX | EXP | TYPE | DISP | WIDTH | HEIGHT | X | Y gkbasefreq, ihbasefreq FLslider "Base Frequency", 20, 20000, -1, 5, idbasefreq, 400, 30, 0, 50 gkindex, ihindex FLslider "Modulation Index", 0, 50, 0, 5, idindex, 400, 30, 0, 100 gkCarAmp, ihCarAmp FLslider "Carrier Amplitude", 0, 30000, 0, 5, idCarAmp, 500, 30, 0, 250 ;BORDERS ITYPE, IFONT, ISIZE, IWIDTH, IHEIGHT, IX, IY ih FLbox " ", 6, 9, 15, 220, 70, 140, 160 ; MIN | MAX | STEP | TYPE | WIDTH | HEIGHT | X | Y gkCarRatio, ihCarRatio FLtext " ", .125, 8, .001, 1, 50, 20, 190, 170 gkModRatio, ihModRatio FLtext " ", .125, 8, .001, 1, 50, 20, 260, 170 gkPeakDev, gihPeakDev FLtext "Peak Deviation", 0, 10000, 0, 1, 80, 20, 410, 65 ;DISPLAY ONLY! ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox ":", 1, 5, 14, 5, 15, 248, 172 ih FLbox "Carrier Frequency", 1, 5, 12, 90, 15, 170, 200 ih FLbox "Modulator Frequency", 1, 5, 12, 90, 15, 245, 200 FLsetVal_i 100, ihbasefreq FLsetVal_i 3, ihindex FLsetVal_i 1, ihCarRatio FLsetVal_i 1, ihModRatio FLsetVal_i 20000, ihCarAmp FLpanel_end ;INSTRUCTIONS AND INFO PANEL FLpanel " ", 500, 560, 512, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox " FM Synthesis: Simple Modulator->Carrier ", 1, 5, 14, 490, 15, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 490, 15, 5, 20 ih FLbox "This example also employs a simple modulator carrier pairing.", 1, 5, 14, 490, 15, 5, 40 ih FLbox "This time, however, the FM implementation and the parameters ", 1, 5, 14, 490, 15, 5, 60 ih FLbox "presented to the user are more typical (and more usable). ", 1, 5, 14, 490, 15, 5, 80 ih FLbox "The 'Index of Modulation' is used to control the spectral ", 1, 5, 14, 490, 15, 5, 100 ih FLbox "intensity (brightness) of the FM timbre. This value is used ", 1, 5, 14, 490, 15, 5, 120 ih FLbox "in the formula: 'Peak Deviation = Index * Base Frequency' to ", 1, 5, 14, 490, 15, 5, 140 ih FLbox "calculate the Peak Deviation (amplitude) of the modulator ", 1, 5, 14, 490, 15, 5, 160 ih FLbox "within the code. A value box for peak deviation is provided ", 1, 5, 14, 490, 15, 5, 180 ih FLbox "to inform the user how its value changes in relation to ", 1, 5, 14, 490, 15, 5, 200 ih FLbox "changes made to the base frequency and the index of ", 1, 5, 14, 490, 15, 5, 220 ih FLbox "modulation. The value for peak deviation can not be directly ", 1, 5, 14, 490, 15, 5, 240 ih FLbox "modified by the user, its value box in the interface is for ", 1, 5, 14, 490, 15, 5, 260 ih FLbox "display purposes only. ", 1, 5, 14, 490, 15, 5, 280 ih FLbox "The frequencies of the carrier and modulator are calculated ", 1, 5, 14, 490, 15, 5, 300 ih FLbox "in relation to 'Base Frequency' using a ratio between the ", 1, 5, 14, 490, 15, 5, 320 ih FLbox "carrier frequency and the modulator frequency. This practice ", 1, 5, 14, 490, 15, 5, 340 ih FLbox "makes it easier for the user to see when the two frequencies ", 1, 5, 14, 490, 15, 5, 360 ih FLbox "are in a simple ratio with respect to each other. ", 1, 5, 14, 490, 15, 5, 380 ih FLbox "Although the code for this example makes use of two separate ", 1, 5, 14, 490, 15, 5, 400 ih FLbox "'oscili' (oscillator) opcodes for the modulator and carrier ", 1, 5, 14, 490, 15, 5, 420 ih FLbox "an opcode exists that will allow the FM carrier modulator ", 1, 5, 14, 490, 15, 5, 440 ih FLbox "pair to be implemented in a single line (foscil/foscili). The", 1, 5, 14, 490, 15, 5, 460 ih FLbox "advantage of emplying separate 'oscili's is that a better ", 1, 5, 14, 490, 15, 5, 480 ih FLbox "understanding of the innards of FM synthesis is gained and ", 1, 5, 14, 490, 15, 5, 500 ih FLbox "also that the algorithm can easily be expanded to create more", 1, 5, 14, 490, 15, 5, 520 ih FLbox "complex multi-modulator and multi-carrier algorithms. ", 1, 5, 14, 490, 15, 5, 540 FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; instr 1 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 kpeakdeviation = gkbasefreq * gkindex ;CALCUALATE THE PEAK DEVIATION OF THE MODULATOR FROM THE VALUES GIVEN FOR BASE FREQUENCY AND THE INDEX OF MODULATION ;OUTPUT OPCODE AMPLITUDE | FREQUENCY | FUNCTION_TABLE aModulator oscili kpeakdeviation, gkbasefreq * gkModRatio, 1 ;DEFINE THE MODULATOR WAVEFORM aCarrier oscili gkCarAmp, (gkbasefreq * gkCarRatio) + aModulator, 1 ;DEFINE THE CARRIER WAVEFORM (NOTE HOW ITS FREQUENCY IS MODULATED (THROUGH ADDITION) BY THE AUDIO OUTPUT OF THE MODULATOR WAVEFORM) outs aCarrier, aCarrier ;SEND THE AUDIO OUTPUT OF THE CARRIER WAVEFORM *ONLY* TO THE OUTPUTS ktrig metro 10 ;CREATE A REPEATING TRIGGER SIGNAL FLsetVal ktrig, kpeakdeviation, gihPeakDev ;UPDATE VALUE BOX 'gihPeakDev' WITH THE VALUE kpeakdeviation WHENEVER A TRIGGER PULSE IS RECEIVED endin f 1 0 129 10 1 ;A SINE WAVE (INTERPOLATING OSCILLATOR OPCODES ARE USED THEREFORE A SMALL TABLE SIZE (+1) CAN BE USED) f 0 3600 ;DUMMY SCORE EVENT - KEEPS REALTIME PERFORMANCE GOING FOR ONE HOUR