13.3.1 Setting the graphics state

The graphics state values associated with a drawing function call are set by one of three mechanisms.

1. Enumeration in the drawing function call. For example:

(draw-line port
 1 1 100 100  

           :thickness 10

           :scale-thickness nil

           :foreground :red)

2. Bound using the with-graphics-state macro. For example:

(with-graphics-state (port
 :thickness 10

                           :scale-thickness nil

                           :foreground :red)

  (draw-line port
 1 1 100 100)

  (draw-rectangle port
 2 2 40 50 :filled t))

3. Set by the set-graphics-state function. For example:

(set-graphics-state port
 :thickness 10

                    :scale-thickness nil

                    :foreground :red)

The first two mechanisms change the graphics state temporarily. The last one changes it permanently in port , effectively altering the "default" state.

CAPI User Guide (Unix version) - 30 Aug 2011