Three perpendicular lines create a cube.
Two parallel lines drawn in the same direction create a cylinder.
Two non-axis aligned lines that meet at a point create a cone.
Two non-axis aligned lines that do not meet at a point create a truncated cone.
A closed curve followed by a dot create a sphere.
Two perpendicular axis-aligned lines and a dot create a pyramid.
Three axis-aligned lines which do not meet exactly at a point create a superquadric.
Two pairs of perpendicular axis-aligned lines create a truncated pyramid.
Two perpendicular axis-aligned lines and two parallel lines create a triprism.
Two perpendicular axis-aligned lines followed by a curve create an extruded rectangle.
An unclosed curve creates an object of revolution.
A non-axis aligned line, a series of dots forming a closed polyline, then an axis of extrusion create an extruded polyline.
A closed curve, an axis-aligned line, and a curve create a duct. The line is the normal of the plane in which the curve lies.
Clicking and dragging the first mouse button with the shift key pressed draws on the surface beneath the cursor.