beginShape() and endShape() test

size(500, 100, P3D);
background(200);

beginShape(POINTS);
stroke(255,0,0);vertex(30, 20);
stroke(0,0,255);vertex(85, 20);
stroke(0,255,0);vertex(85, 75);
stroke(255,0,0);vertex(30, 75);
endShape(CLOSE);

beginShape(POINTS);
stroke(0,0,255);vertex(130, 20);
stroke(255,0,0);vertex(185, 20);
stroke(255,0,0);vertex(185, 75);
endShape(CLOSE);

beginShape(POINTS);
stroke(0,0,0);vertex(230, 20);
stroke(255,0,0);vertex(285, 20);
endShape(CLOSE);

beginShape(POINTS);
stroke(0,0,255);vertex(330, 20);
endShape(CLOSE);