[Oberon] SystemV - Simple Graph

[Tomas Kral]

Hi,

I do this to clip `Rect' to `Frame', while it appears to do visual
things hopefully right, I am thinking if could coded better?

  PROCEDURE Clip*(VAR x, y, w, h: INTEGER);
  BEGIN
    IF f # NIL THEN
      IF x < f.X THEN w := w-f.X+x; x := f.X END ; IF y < f.Y THEN h := h-f.Y+y; y := f.Y END ;
      IF x+w > f.X+f.W THEN w := f.X+f.W-x END ; IF y+h > f.Y+f.H THEN h := f.Y+f.H-y END
    END
  END Clip;

-- 
Tomas Kral <thomas.kral at email.cz>