MooKeyboard.java

   1 import javax.sound.midi.*;
   2 import java.awt.event.*;
   3
   4 /**
   5  * A keyboard listener emulating a synthesizer.
   6  *
   7  * @author  Einar Pehrson
   8  */
   9
  10 public class MooKeyboard extends KeyAdapter {
  11
  12         private boolean[] isOn;
  13         private static int startNote;
  14         private static int[] keyToNote = new int[120];
  15
  16         /**
  17          * Sets up the synthesizer emulation.
  18          */
  19         public MooKeyboard() {
  20                 isOn = new boolean[120];
  21         }
  22
  23         static {
  24                 startNote = 48;
  25                 makeKeyboardMapping();
  26         }
  27
  28         /**
  29          * Plays the appropriate MIDI NoteOn event.
  30          */
  31         public void keyPressed(KeyEvent e) {
  32                 if (!e.isControlDown()) {
  33                         try {
  34                                 // Retrieves the notenumber from the conversion array.
  35                                 int noteNumber = keyToNote[e.getKeyCode()];
  36                                 // If note is not already on and the key is mapped to a note, sends the NoteOn event.
  37                                 if (!isOn[noteNumber] && noteNumber > 0) Moosique.getActiveChannel().noteOn(noteNumber, 127);
  38                                 isOn[noteNumber] = true;
  39                         } catch (ArrayIndexOutOfBoundsException x) {
  40                                 return;
  41                         }
  42                 }
  43         }
  44
  45         /**
  46          * Plays the appropriate MIDI NoteOff event.
  47          */
  48         public void keyReleased(KeyEvent e) {
  49                 if (!e.isControlDown()) {
  50                         try {
  51                                 // Retrieves the notenumber from the conversion array.
  52                                 int noteNumber = keyToNote[e.getKeyCode()];
  53                                 // Sends the NoteOff event.
  54                                 Moosique.getActiveChannel().noteOff(noteNumber);
  55                                 isOn[noteNumber] = false;
  56                         } catch (ArrayIndexOutOfBoundsException x) {
  57                                 return;
  58                         }
  59                 }
  60         }
  61
  62         /**
  63          * Sets the octave of the lower part of the keyboard (default = 4)
  64          * @param n     the octave to start at
  65          */
  66         public static void setOctave(int n) {
  67                 startNote = n * 12;
  68                 makeKeyboardMapping();
  69         }
  70
  71         /**
  72          * Increases or decreases the octave of the lower part of the keyboard (default = 4)
  73          * @param increase      true for increase, false for decrease
  74          */
  75         public static void setRelativeOctave(boolean increase) {
  76                 if (increase) {
  77                         if (startNote == 108) return;
  78                         setOctave((startNote/12) + 1);
  79                 } else {
  80                         if (startNote == 0) return;
  81                         setOctave((startNote/12) - 1);
  82                 }
  83         }
  84
  85         /** Maps keycodes (array indices) to MIDI note numbers using the following layout:
  86          *
  87          *  2 3   5 6 7   9 0   =>  # #   # # #   # #
  88          * q w e r t y u i o p  => c d e f g a b c d e
  89          *  s d   g h j   l     =>  # #   # # #   #
  90          * z x c v b n m , .    => c d e f g a b c d
  91          */
  92         private static void makeKeyboardMapping() {
  93                 keyToNote[KeyEvent.VK_Q] = startNote;
  94                 keyToNote[83] = startNote + 1;
  95                 keyToNote[88] = startNote + 2;
  96                 keyToNote[68] = startNote + 3;
  97                 keyToNote[67] = startNote + 4;
  98                 keyToNote[86] = startNote + 5;
  99                 keyToNote[71] = startNote + 6;
 100                 keyToNote[66] = startNote + 7;
 101                 keyToNote[72] = startNote + 8;
 102                 keyToNote[78] = startNote + 9;
 103                 keyToNote[74] = startNote + 10;
 104                 keyToNote[77] = startNote + 11;
 105                 keyToNote[44] = startNote + 12;
 106                 keyToNote[76] = startNote + 13;
 107                 keyToNote[46] = startNote + 14;
 108                 keyToNote[81] = startNote + 12;
 109                 keyToNote[50] = startNote + 13;
 110                 keyToNote[87] = startNote + 14;
 111                 keyToNote[51] = startNote + 15;
 112                 keyToNote[69] = startNote + 16;
 113                 keyToNote[82] = startNote + 17;
 114                 keyToNote[53] = startNote + 18;
 115                 keyToNote[84] = startNote + 19;
 116                 keyToNote[54] = startNote + 20;
 117                 keyToNote[89] = startNote + 21;
 118                 keyToNote[55] = startNote + 22;
 119                 keyToNote[85] = startNote + 23;
 120                 keyToNote[73] = startNote + 24;
 121                 keyToNote[57] = startNote + 25;
 122                 keyToNote[79] = startNote + 26;
 123                 keyToNote[48] = startNote + 27;
 124                 keyToNote[80] = startNote + 28;
 125         }
 126 }