This example is for Processing 3+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.

Continuous Lines.

Click and drag the mouse to draw a line.

void setup() {
  size(640, 360);

void draw() {
  if (mousePressed == true) {
    line(mouseX, mouseY, pmouseX, pmouseY);