int         len        = 5;
PGraphics[] pg         = new PGraphics[len];
int[]       xPos       = new int[len];
int         xPosGutter = 5;

void setup() {
	size(800, 600);
	for (int i = 0; i < len; i++) {
		pg[i] = createGraphics( (width/len)-xPosGutter, height );
		xPos[i] = (width/len) * i;
	}
}

void draw() {
	for (int i = 0; i < len; i++) {
		pg[i].beginDraw();
			pg[i].clear();
			pg[i].background( (i*25)+50 );
			pg[i].noStroke();
			pg[i].fill( (int)random(255), i*50, 0 );
			pg[i].ellipse((int)random(width/len), (int)random(height), 20, 20);
		pg[i].endDraw();

		image(pg[i], xPos[i], 0);
	}
}