RGB LED Servo 3

// continuously move a servo while an RGB LED continuously updates its color

#include <Servo.h>

Servo servo;


const int servoRestPosition   = 0;    //Starting position
const int servo90Position   = 90;     //90 degrees
const int servoTargetPosition = 180;  //Position when event is detected

#define GREEN 3
#define BLUE 5
#define RED 6
#define delayTime 20

void setup() {

  Serial.begin(9600);
  Serial.println("start");

  servo.attach(9);
  servo.write(servoRestPosition);

  analogWrite(RED, 0);
  analogWrite(GREEN, 0);
  analogWrite(BLUE, 0);

  delay(250);
}



int currentServoPosition = 0;     // keep track of servo position
int inc_dec = 1;                  // use to increment/decrement servo position

void loop() {

  int redVal = 255;
  int blueVal = 0;
  int greenVal = 0;
  for( int i = 0 ; i < 255 ; i += 1 )
  {
    greenVal += 1;
    redVal -= 1;
    analogWrite(GREEN, 255 - greenVal );
    analogWrite(RED, 255 - redVal );

    updateServoPosition(i);

    delay( delayTime );
  }

  redVal = 0;
  blueVal = 0;
  greenVal = 255;
  for( int i = 0 ; i < 255 ; i += 1 )
  {
    blueVal += 1;
    greenVal -= 1;
    analogWrite(BLUE, 255 - blueVal );
    analogWrite(GREEN, 255 - greenVal );

    updateServoPosition(i);

    delay( delayTime );
  }


  redVal = 0;
  blueVal = 255;
  greenVal = 0;
  for( int i = 0 ; i < 255 ; i += 1 )
  {
    redVal += 1;
    blueVal -= 1;
    analogWrite(RED, 255 - redVal );
    analogWrite(BLUE, 255 - blueVal );

    updateServoPosition(i);

    delay( delayTime );
  }

}  //loop()


void updateServoPosition(int i)
{

    if( i % 2 == 0 )    // if i is an even number, then we will move the servo by 1 degree 
                        // arbitrarily decided to update at this frequency 
                        // adjust to your own preferences
      { 
        servo.write(currentServoPosition); 

        currentServoPosition = currentServoPosition + inc_dec;

        //reverse direction upon reachin servo limits
        if ( currentServoPosition >= 180 )
          { inc_dec = -1; }
        else if( currentServoPosition <= 0 )
          { inc_dec = 1; }
      }

}