Single LED color chaser

Rainbow.ino

#include <Bridge.h>
#include <Console.h>

int red = 11;
int green = 10;
int blue = 9;
int redLevel = 255;
int greenLevel = 0;
int blueLevel = 0;
int defaultStep = 5;
int redStep = -defaultStep;
int greenStep = defaultStep;
int blueStep = 0;
int velocity = 0;
int velocityLevel = 127;

void setup()  {
  pinMode(red, OUTPUT);
  pinMode(green, OUTPUT);
  pinMode(blue, OUTPUT);
  pinMode(velocity, INPUT);
}

void loop()  {
  analogWrite(red, redLevel);
  analogWrite(green, greenLevel);
  analogWrite(blue, blueLevel);
  velocityLevel = analogRead(velocity);

  redLevel = redLevel + redStep;
  greenLevel = greenLevel + greenStep;
  blueLevel = blueLevel + blueStep;

  if (redLevel == 0 && redStep != 0) {
    redStep = 0;
    blueLevel = defaultStep;
    blueStep = defaultStep;
  } else if (redLevel == 255) {
    redStep = -defaultStep;
  }

  if (greenLevel == 0 && greenStep != 0) {
    greenStep = 0;
    redLevel = defaultStep;
    redStep = defaultStep;
  } else if (greenLevel == 255) {
    greenStep = -defaultStep;

  }

  if (blueLevel == 0 && blueStep != 0) {
    blueStep = 0;
    greenLevel = defaultStep;
    greenStep = defaultStep;
  } else if (blueLevel == 255) {
    blueStep = -defaultStep;
  }

  delay((velocityLevel / 20) + 1);
}