MIDIControllerInitialisation.csd Written by Iain McCurdy 2006. Updated 2011. -odac -Ma -dm0 sr = 44100 ;SAMPLE RATE ksmps = 4 ;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 ;INSTRUCTIONS AND INFO PANEL WIDTH | HEIGHT | X | Y FLpanel "initc7", 535, 600, 0, 0 FLscroll 535, 600, 0, 0 ;TEXT BOXES TYPE | FONT | SIZE | WIDTH | HEIGHT | X | Y ih FLbox "initc7 - Setting an Initial Value for a Continuous Controller", 1, 5, 14, 510, 20, 5, 0 ih FLbox "-------------------------------------------------------------", 1, 5, 14, 510, 20, 5, 20 ih FLbox "This example builds upon the previous example in that it ", 1, 5, 14, 510, 20, 5, 40 ih FLbox "demonstrates how to set the initial value of a continuous ", 1, 5, 14, 510, 20, 5, 60 ih FLbox "controller used in a csound orchestra. ", 1, 5, 14, 510, 20, 5, 80 ih FLbox "If no initial value is defined then then a ctrl7's output ", 1, 5, 14, 510, 20, 5, 100 ih FLbox "defaults to its minimum value. ", 1, 5, 14, 510, 20, 5, 120 ih FLbox "The opcode initc7 is used to set an initial value for ctrl7. ", 1, 5, 14, 510, 20, 5, 140 ih FLbox "initc7 is normally placed in the instrument 0 part of the ", 1, 5, 14, 510, 20, 5, 160 ih FLbox "orchestra (after the orchestra header and before the first ", 1, 5, 14, 510, 20, 5, 180 ih FLbox "instrument) so that the controller is initialised only when ", 1, 5, 14, 510, 20, 5, 200 ih FLbox "the orchestra is started. If it is placed within an ", 1, 5, 14, 510, 20, 5, 220 ih FLbox "instrument then it will be initialised each time that ", 1, 5, 14, 510, 20, 5, 240 ih FLbox "instrument is activated - it is unlikely that this will be ", 1, 5, 14, 510, 20, 5, 260 ih FLbox "the desired behaviour. ", 1, 5, 14, 510, 20, 5, 280 ih FLbox "Giving initc7 an intialisation value is not entirely ", 1, 5, 14, 510, 20, 5, 300 ih FLbox "straightforward. We cannot give initc7 the actual value we ", 1, 5, 14, 510, 20, 5, 320 ih FLbox "desire as because initc7 appears before ctrl7 Csound does not", 1, 5, 14, 510, 20, 5, 340 ih FLbox "yet know the range of the controller. Instead, initc7 expects", 1, 5, 14, 510, 20, 5, 360 ih FLbox "a value within the range 0 - 1, with a value of zero ", 1, 5, 14, 510, 20, 5, 380 ih FLbox "representing the controller's minimum setting and a value of ", 1, 5, 14, 510, 20, 5, 400 ih FLbox "1 representing the controller's maximum setting. Csound will ", 1, 5, 14, 510, 20, 5, 420 ih FLbox "subsequently adjust this value when it encounters the ctrl7 ", 1, 5, 14, 510, 20, 5, 440 ih FLbox "line of code. Normally we are more concerned with the precise", 1, 5, 14, 510, 20, 5, 460 ih FLbox "value of ctrl7's output therefore it is useful to use the ", 1, 5, 14, 510, 20, 5, 480 ih FLbox "formula given below to calculate the corresponding value to ", 1, 5, 14, 510, 20, 5, 500 ih FLbox "give initc7. ", 1, 5, 14, 510, 20, 5, 520 ih FLbox "*************************************************************", 1, 5, 14, 510, 20, 5, 540 ih FLbox " Desired_Controller_Value - Controller_Minimum", 1, 5, 14, 510, 20, 5, 560 ih FLbox "Initial__Value =_____________________________________________", 1, 5, 14, 510, 20, 5, 580 ih FLbox " ", 1, 5, 14, 510, 20, 5, 600 ih FLbox " Controller_Maximum - Controller_Minimum", 1, 5, 14, 510, 20, 5, 620 ih FLbox "*************************************************************", 1, 5, 14, 510, 20, 5, 640 ih FLbox "Note that this formula will not work if the midi controller ", 1, 5, 14, 510, 20, 5, 660 ih FLbox "is rescaled using a non-linear function table when it is ", 1, 5, 14, 510, 20, 5, 680 ih FLbox "declared using ctrl7. ", 1, 5, 14, 510, 20, 5, 700 ih FLbox "In this example the volume controller is initialised to its ", 1, 5, 14, 510, 20, 5, 720 ih FLbox "maximum setting and initc7 is therefore given the value '1' ", 1, 5, 14, 510, 20, 5, 740 ih FLbox "for an initial state. ", 1, 5, 14, 510, 20, 5, 760 FLscroll_end FLpanel_end FLrun ;RUN THE FLTK WIDGET THREAD ;END OF FLTK INTERFACE CODE;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;The opcode 'initc7' initialises a continuous controller to a specified location between ;its minimum and maximum value. ;This initialisation value is expressed as a propotion of how far along its path from ;minimum to maximum it should begin and is therefore always a number in the range 0-1. ;A value of 0 would imply that the slider begins at its lowest setting. ;A value of 1 would imply that the slider begins at its highest setting. ;A value of .5 would imply that the slider begins halfway along its track. ;If you require a midi controlled variable to begin at a specific value the required ;initialisation value can be calculated using the formula shown below. ;Initialisation defaults to 0 so if you require a controller to begin at minimum it is ;not necessary to initialise it. ;NOTE THAT ONCE A SLIDER IS PHYSICALLY MOVED ITS CORRESPONDING CSOUND VARIABLE IMMEDIATELY ;JUMPS TO THAT NEW VALUE ;NOTE ALSO THAT THIS INITIALISATION STATEMENT IS PLACED BETWEEN THE HEADER STATEMENTS AND THE ;FIRST INSTRUMENT DEFINITION (known as the instr 0 definition) - THIS MEANS THAT THE CONTROLLER ;WILL BE INITIALISED UPON BEGINNING THE CSOUND SESSION *ONLY* ;IF THE INITIALISATION STATEMENT IS PLACED WITHIN THE INSTRUMENT CODE ITSELF IT WILL REINITIALISE ;EACH TIME A NEW NOTE IS PLAYED ; MIDICHANNEL | CTRLNUMBER | VALUE(0-1) initc7 1, 1, 1 ;************************************************************************************** ;* * ;* Desired_Controller_Value - Controller_Minimum * ;* Initial__Value = _____________________________________________________ * ;* * ;* Controller_Maximum - Controller_Minimum * ;* * ;************************************************************************************** giwave ftgen 0,0,4096,10,1,1/4,1/9,1/16,1/25,1/36,1/49,1/64,1/81 instr 1 ; SIMPLE BEEP INSTRUMENT - CAN BE ACTIVATED VIA A CONNECTED MIDI KEYBOARD icps cpsmidi iamp ampmidi 0.2 ;OUTPUT OPCODE CHANNEL | CTRLNUMBER | MINIMUM | MAXIMUM kvolume ctrl7 1, 1, 0, 1 ;READ CONTROLLER INFORMATION FROM CONTINUOUS CONTROLLER NUMBER 1 ON MIDI CHANNEL 1 AND RESCALE TO BE WITHIN THE RANGE 0 - 1 kporttime linseg 0, .001, .01, 1, .01 ;CREATE A RAMPING UP FUNCTION THAT WILL BE USED FOR PORTAMENTO TIME - THIS WILL PREVENT PORTAMENTO-ED VARIABLES FROM GLIDING UP TO THEIR DESIRED VALUES AT NOTE ONSETS kvolume portk kvolume, kporttime ;APPLY PORTAMENTO TO kvolume TO SMOOTH ITS MOVEMENT ; INITIAL_LEVEL | ATTACK_TIME | ATTACK_LEVEL | DECAY_TIME | SUSTAIN_LEVEL | RELEASE_TIME | RELEASE_LEVEL aenv linsegr 0, (.01), 1, (.1), .7, (.05), 0 asig poscil iamp,icps,giwave out asig * aenv * kvolume endin f 0 600 ; THIS LINE FUNCTIONS AS A DUMMY SCORE EVENT AND ALLOWS REALTIME MIDI PLAYING FOR 10 MINUTES