Jacobs Ladder Motion Study

float angle = 0;

float speed = 0.02;

int a;

int h;

float modulo;

int var = 1;

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void setup() {

  size (500, 500);

  smooth();

  background(255);

  stroke(0);

  strokeWeight(3);

  fill(100);

​

  h = height/10;

​

​

  for (int i=h; i<=height; i+=h) {

    rect(0, i-h, width, i);

  }

}

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void draw() {

  if (var>0) {

    fill(100);

  }

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  else if (var<0) {

    fill(200);

  }

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  a=0;

​

​

  if (angle<PI/2-speed) {

    float delta = h*abs(cos(angle));

    background(255);

    rect(0, delta, width, h-2*delta);

​

    for (int i=0; i<height-h; i+=h) {

      rect(0, delta+i, width, h);

    }

​

    angle+=speed;

  }

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  if (angle>=PI/2-speed && angle<PI/2) {

    float delta = h*abs(cos(angle));

    background(255);

    rect(0, delta, width, h-2*delta);

​

    for (int i=0; i<height-h; i+=h) {

      rect(0, delta+i, width, h);

    }

​

    angle+=speed;

    var*=-1;

  }

​

  for (float step=PI/2; step<20*PI/2; step+=PI) {

    modulo = ((step*2/PI)-1) % 4;

​

    if (modulo == 0) {

      if (angle>step && angle<=step+PI/2) {

        float delta = h*abs(cos(angle));

        rect(0, a, width, delta);

        angle+=speed;

      }

​

​

​

      else if (angle>step+PI/2 && angle<=step+PI) {

        float delta = h*abs(cos(angle));

        rect(0, a+h, width, h-delta);

        angle+=speed;

      }

​

      a+=2*h;

    }

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    else if (modulo != 0) {

      if (angle>step && angle<=step+PI) {

        float delta = h*abs(cos(angle));

        angle+=speed;

      }

    }

  }

​

  if (angle>=10*PI) {

    a=0;

    angle=0;

  }

}   

​

​