You can paint straight lines quickly using the line tool. The line tool is most useful for painting wires out of images using the Merge or Clone brushes (see Setting the Brush Offset).
Edit the paint operator that you want to paint on, as described in Editing and Previewing Paint Operators.
Choose a brush from the Fx Brush Selector and edit its properties as described in Setting Paint Brush Properties.
If necessary, choose a color as described in Choosing Colors with the Fx Color Selector.
From the Paint menu in the Fx viewer, choose Draw 
Line Tool.
Alternatively, you can position the mouse pointer over the Fx viewer and press N.
In the Fx viewer, click at the point where you want the line to begin and drag the paint cursor to the point where you want it to end.
As you drag, the paint cursor is stretched out from the initial click point, providing a guide for where the line will appear. The guide's width indicates the line's width.
The line is applied to the currently displayed frame in the Fx Viewer, using the specified foreground color.
Using the Line Tool in Vector Paint Operators
Like the paint brush tool, the line tool works the same in vector paint operators as it does in raster paint clips. However, in vector paint operators, drawing a line creates a two-point color shape drawn using the outline (stroke) only (see Setting the Shape Type for more information about shape properties).
Once you've drawn a line, you can modify and animate it as you would any other color shape.
For information about editing color shape properties, see Blurring Color Shape Edges.
For information about transforming shapes, see Transforming Shapes.
For information about editing shape points, see Editing Shape Points.
For information about animating shapes, see Animating Other Shape Parameters.
