        line(30, 20, 85, 75);

line(30, 20, 85, 20);
stroke(126);
line(85, 20, 85, 75);
stroke(255);
line(85, 75, 30, 75);

//Intentionally bad code ;)
line(30, 20, 0, 85, 20, 15);
stroke(126);
line(85, 20, 15, 85, 75, 0);
stroke(255);
line(85, 75, 0, 30, 75, -50);

There is no P3D renderer.

The original line() function example showed also the ability to draw in 3D space. That is still not implemented in P5, but the example is still here as a comparison.