public void drawLine(int x1, int y1, int x2, int y2) {
PPath pn = PPath.createLine(x1, y1, x2, y2);
pn.setStrokePaint(currentPenColor);
pn.setPaint(null); // Null paint may render faster than the default.
pn.setStroke(stroke);
pn.moveTo(x1, y1);
pn.lineTo(x2, y2);
layer.addChild(pn);
}
/**