Triangle

Drag a mouse like joining each vertex at the other side of the vertex which two lines share and you can create a new triangle.

Original		Click the vertex A, and drag to the vertex B.		Release a mouse button near the vertex B, and a new triangle is created.

Or, you can also make it by dragging an existing line.

Original		Drag the edge,		Release a mouse button, and a new triangle is created.

And when you create a triangle by dragging an edge, you can snap a new triangle to the existing vertex by clicking a right button with pressing a left button near the vertex.

Original		Drag the edge,		Click a right button near the vertex B with pressing a left button, and a new triangle shared the vertex is created.

Quadrangle

It pulls a face of a quadrangle includes the selected line. It is more convenient than [Create] command because you need to drag a mouse only once.

Two lines are selected		Drag		New faces are created

When you drag with Shift-key, vertices will be moved to the horizontal or the vertical direction only.

And if you press the right button while dragging a mouse, one side of vertices will be joined to the existing vertex.

Drag from this line
Click a right button in this state		A vertex in the new face is merged to the vertex in the other face

You can create a face by specifying the line length. Enter the length in the number field and click [OK].

Select a line		Enter the length of another line		Click [OK] and create a face