region%

A region% object specifies a portion of a drawing area (possibly discontinuous) for clipping drawing operations.

Each region% object is associated to a particular dc<%> object, specified when the region is created. A region can only be used with its associated dc<%> object, and changing the origin or scale of a drawing context invalidates its associated regions. (The region can still be used after the origin or scale is chaged, but the results are platform- and device-dependent.)

See also set-clipping-region in dc<%> and get-clipping-region in dc<%>.

• (make-object region% dc) -> region% object
      dc : dc<%> object

  Creates an empty region.

  
  

• get-bounding-box
• get-dc
• intersect
• is-empty?
• set-arc
• set-ellipse
• set-polygon
• set-rectangle
• set-rounded-rectangle
• subtract
• union