Class2_PWM multiple time management

/*
Fade RGB LEDs
 This example shows how to fade an LED on pin 3,5,6
 using the analogWrite() function.
 This example code is in the public domain.
 */
int brightnessBlue = 0; // how bright the BLUE LED is
int fadeAmountBlue = 1; // how many points to fade the BLUE LED by
long incrementTimeBlue = 10;
long desiredTimeBlue = incrementTimeBlue;

int brightnessGreen = 85; // how bright the GREEN LED is
int fadeAmountGreen = 2; // how many points to fade the BLUE LED by
long incrementTimeGreen = 10;
long desiredTimeGreen = incrementTimeGreen;

int brightnessRed = 170; // how bright the RED LED is
int fadeAmountRed = 3; // how many points to fade the BLUE LED by
long incrementTimeRed = 10;
long desiredTimeRed = incrementTimeRed;

void setup() {
  // declare pin 9 to be an output:
  pinMode(3, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // set the brightness of pin 3, 5, and 6:
  analogWrite(3, brightnessBlue);
  analogWrite(5, brightnessGreen);
  analogWrite(6, brightnessRed);
  // BLUE LED LOGIC BEGIN
  // change the brightness for next time through the loop:
  if( millis() >= desiredTimeBlue){
    brightnessBlue += fadeAmountBlue;
    desiredTimeBlue += incrementTimeBlue;
  }

  // reverse the direction of the fading at the ends of the fade:
  if (brightnessBlue <= 0 || brightnessBlue >= 255) {
    fadeAmountBlue *= -1 ;
    brightnessBlue += fadeAmountBlue;
  }
  // BLUE LED LOGIC END

  // GREEN LED LOGIC BEGIN
  // change the brightness for next time through the loop:
  if( millis() >= desiredTimeGreen){
    brightnessGreen += fadeAmountGreen;
    desiredTimeGreen += incrementTimeGreen;
  }

  // reverse the direction of the fading at the ends of the fade:
  if (brightnessGreen <= 0 || brightnessGreen >= 255) {
    fadeAmountGreen *= -1 ;
    brightnessGreen += fadeAmountGreen;
  }
  // GREEN LED LOGIC END

  // RED LED LOGIC BEGIN
  // change the brightness for next time through the loop:
  if( millis() >= desiredTimeRed){
    brightnessRed += fadeAmountRed;
    desiredTimeRed += incrementTimeRed;
  }

  // reverse the direction of the fading at the ends of the fade:
  if (brightnessRed <= 0 || brightnessRed >= 255) {
    fadeAmountRed *= -1 ;
    brightnessRed += fadeAmountRed;
  }
  // RED LED LOGIC END
  // wait for 30 milliseconds to see the dimming effect
  //delay(30);
}