createCanvas(400, 400);

}

​

function draw() {

  background(220);

    // translate(0, 0);

  fill(0)

  // beginShape()

  // rect(0,0, width, height)

  // beginContour()

  // rect(0,0, width, height, 50)

  // endContour();

  // endShape(CLOSE)

  translate(0, 0);

beginShape();

// Exterior part of shape, clockwise winding

vertex(0, 0);

vertex(width, 0);

vertex(width, height);

vertex(0, height);

// Interior part of shape, counter-clockwise winding

beginContour();

​

// vertex(30, 20);

// curveVertex(20, 30);

//   vertex(20, height-30);

// curveVertex(30, height-20);

//   vertex(width-30, height-20);

// curveVertex(width-20, height-30);

//   vertex(width-20, 30);

//  curveVertex(width-30, 20);

//   vertex(30, 20);

  vertex(30, 20);

vertex(20, 30);

  vertex(20, height-30);

vertex(30, height-20);

  vertex(width-30, height-20);

vertex(width-20, height-30);

  vertex(width-20, 30);

 vertex(width-30, 20);

  vertex(30, 20);

​

​

endContour();

endShape(CLOSE);

}