Train with Tracks using Arrays and For Loops

float trainX;

float trainY = 0;

float trainSpeed = 1;

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float trackX1, trackX2;

​

float trackY1 = 0;

float trackY2 = 20;

float trackY3 = 10;

​

float [] trainYpos = new float [20];

​

void setup () {

  size (100, 500);

  trainX = width/2;

​

  trackX1 = width/2-5;

  trackX2 = width/2+15;

​

  for (int i = 0; i < trainYpos.length; i++) { // setting the for loop to save locations of trainY

    trainYpos[i] = i * 20; // this is how apart i want them to be

  }

}

​

void draw () {

  background (100);

​

  // Draw the train track using For Loops!

  strokeWeight (2);

  for (int y = 0; y < height; y = y+10) {

    line (trackX1, trackY1+y, trackX1, trackY2+y);

    line (trackX2, trackY1+y, trackX2, trackY2+y);

    line (trackX1, trackY3+y, trackX2, trackY3+y);

  }

​

// drawing train compartments using for loops + Arrays!

​

// train moves down for ever

  strokeWeight(1.5);

  for (int i = 0; i < trainYpos.length; i++) {

    // ----- to make it come back

    if (trainYpos[i] > height) {

      trainYpos[i] = 0;

    }

    // fill (255, random(255), random(255)); // randome flashing colours

    fill (255, 0, 0);

    rect (trainX, trainYpos[i], 10, 20);

    trainYpos[i] = trainYpos[i] + trainSpeed;

  }

}