Line is a function that draws a line using two points. For most shapes you can set the color using fill() , but a line is only a stroke, so you must use stroke() to set the color.


line(x1, y1, x2, y2);

  • x1 - (float) the first point's x position
  • y1 - (float) the first point's y position
  • x2 - (float) the second point's x position
  • y2 - (float) the second point's y position


void update() 
    // set the stroke color to orange
    stroke(color(255, 160, 20, 255));

    // draw a line from (100, 100) to (100, 200)
    //   x1      y1      x2      y2
    line(100.0f, 100.0f, 500.0f, 100.0f);

    // set the stroke color to light blue
    stroke(color(0, 160, 255, 255));

    // draw a line from the origin to the mouse position
    line(0.0f, 0.0f, mouseX, mouseY);