Continue from last position

Hello, I'm wondering if there is a way chain lines (and others) for
example;
0.5 0.0
to
1.0 1.0            TRIANGLE
to
0.0 1.0
to
0.5 0.0

rather than having to draw them individually, disconnected:

0.5 1.0
to
1.0 1.0

1.0 1.0
to
0.0 1.0

to

0.0 1.0
to
0.5 0.0