On the fly key mapping

gistfile1.ino

//discover correct keyCodes
static void calcKeyCodes(){
  //a special case for caps lock
  //switch caps lock and submit
  if((modifiers[0] & M2L->keyCode) && (modifiers[0] & M2R->keyCode)){
    modifiers[0] = 0x00;
    keyCodes[0] = KC_CAPSLOCK;
    keyCodeIndex = 1;
      
    if(!capslock){
      capslock = true;
    }
    else{
      capslock = false;
    }
  }
  else {
    //iterate over all pressed keys
    for(int i = 0; i < pressedKeyIndex; i++){
      if(keyCodeIndex < MAX_KEYS_PRESSED){
        Key * key = pressedKeys[i];
        //no modifiers, special case for acute sign
        if(noModifiers()){ 
          if(key == ACUTE2){ 
            enableShift();
            keyCodes[keyCodeIndex] = key->keyCode;
            keyCodeIndex++;
          }
          else {
            keyCodes[keyCodeIndex] = key->keyCode;
            keyCodeIndex++;
          }
        }
        else { 
          //shift pressed and number keys
          if(m2Pressed() && key == N6){
            keyCodes[keyCodeIndex] = N4->keyCode;
            keyCodeIndex++;
          }
          else if(m2Pressed() && key == N7){
            enableAlt(); disableShift();
            keyCodes[keyCodeIndex] = E->keyCode;
            keyCodeIndex++;
          }
          //...
          //m3 e.g. alt pressed
          //...
          else if(m3Pressed() && key == H){
            keyCodes[keyCodeIndex] = 0x64;
            keyCodeIndex++;
          }
          else if(m3Pressed() && key == G){
            keyCodes[keyCodeIndex] = 0x64;
            enableShift();
            keyCodeIndex++;
          }
          //...
          //m4 neo2 keys for programming
          //...
          else if(m4Pressed() && key == N6){
            keyCodes[keyCodeIndex] = N4->keyCode;
            enableShift(); enableAlt();
            keyCodeIndex++;
          }
          else if(m4Pressed() && key == N9){
            keyCodes[keyCodeIndex] = KC_7;
            enableShift();
            keyCodeIndex++;
          }
          //...
          else if(m4Pressed() && key == Z){
            keyCodes[keyCodeIndex] = KC_UNDO;
            keyCodeIndex++;
          }
                    
          //no modification necessary
          else {
            keyCodes[keyCodeIndex] = key->keyCode;
            keyCodeIndex++;
          }
        }
      }
    }
  }
}

//some helpers
static boolean m2Pressed(){
  return (modifiers[0] & M2L->keyCode) || (modifiers[0] & M2R->keyCode);
}

static boolean m3Pressed(){
  return modifiers[1] & M3->keyCode;
}

static boolean m4Pressed(){
  return modifiers[1] & M4->keyCode;
}

static boolean noModifiers(){
  return !m2Pressed() && !m3Pressed() && !m4Pressed();
  //return modifiers[1] == 0 && (modifiers[0] & 0x22) == 0
}

static void enableAlt(){
  modifiers[0] = modifiers[0] | ALTL->keyCode;
}

static void disableAlt(){
  modifiers[0] = modifiers[0] & ~ ALTL->keyCode;
  modifiers[0] = modifiers[0] & ~ ALTR->keyCode;
}

static void enableShift(){
  modifiers[0] = modifiers[0] | M2L->keyCode;
}

static void disableShift(){
  modifiers[0] = modifiers[0] & ~ M2L->keyCode;
  modifiers[0] = modifiers[0] & ~ M2R->keyCode;
}