###############################################################################
#                                                                             #
#  Lout @Fig package for drawing figures (Version 2.0)                        #
#                                                                             #
#  Version 1.0 by Jeffrey H. Kingston, October 1991.                          #
#  Version 2.0 by Jeffrey H. Kingston, 22 December 1992.                      #
#  Symbol names changed by JHK 5 March 1993 to avoid clashes with EPS files.  #
#  @CurveBox and @ShadowBox added by JHK April 1995.                          #
#                                                                             #
#  See "Fig - a Lout package for drawing figures" for user information.       #
#                                                                             #
#  This package is now obsolete, having been replaced by @Diag.               #
#                                                                             #
###############################################################################

@SysPrependGraphic { "figf.lpg" }

export in cm pt em sp vs ft dg
       "<<" "**" "++" "--" @Max @Min
       @Distance @XDistance @YDistance @Angle
       @Prev "::" @Label @BaseOf @MarkOf @ShowLabels @Figure
       @Frame @Box @CurveBox @ShadowBox @Square @Diamond @Polygon @Ellipse
       @Circle @HLine @VLine @Line @HArrow @VArrow @Arrow @Arc

def @Fig                  
    named maxlabels  { 200     }
    named linestyle  { solid   }
    named linewidth  { 0.5 pt  }
    named linecap    { round   }
    named dashlength { 0.15 cm }
    named paint      { nopaint }
    named margin     { 0.4c    }
    named arrow      { noarrow }
    named headstyle  { open    }
    named headwidth  { 0.05 cm }
    named headlength { 0.15 cm }
    body @Body
@Begin

    # Like @Graphic, but affects the graphics state of right parameter
    def @InnerGraphic
	left ps
	right x
    {
	    @BackEnd @Case {
	    	PostScript @Yield { { ps gsave // grestore } @Graphic x }
	    	PDF        @Yield { }
	    }
    }

    def in precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "in" }
	    	PDF        @Yield { "__mul(__in, "x")" }
	    }
	}

    def cm precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "cm" }
	    	PDF        @Yield { "__mul(__cm, "x")" }
	    }
	}

    def pt precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "pt" }
	    	PDF        @Yield { "__mul(__pt, "x")" }
	    }
	}

    def em precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "em" }
	    	PDF        @Yield { "__mul(__em, "x")" }
	    }
	}

    def sp precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "sp" }
	    	PDF        @Yield { "__mul(__louts, "x")" }
	    }
	}

    def vs precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "vs" }
	    	PDF        @Yield { "__mul(__loutv, "x")" }
	    }
	}

    def ft precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "ft" }
	    	PDF        @Yield { "__mul(__loutf, "x")" }
	    }
	}

    def dg precedence 39 left x {
	    @BackEnd @Case {
	    	PostScript @Yield { x "dg" }
	    	PDF        @Yield { }
	    }
	}

    def "<<"
	precedence 38
	left length
	right angle
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				0 0 length angle "lfigatangle"
			}
			PDF @Yield {
			}
		}
    }

    def "**"
	precedence 37
	left point
	right length
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				point length "lfigpmul"
			}
			PDF @Yield {
			}
		}
    }

    def "++"
	precedence 36
	associativity left
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigpadd"
			}
			PDF @Yield {
			}
		}
    }

    def "--"
	precedence 36
	associativity left
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				y x "lfigpsub"
			}
			PDF @Yield {
			}
		}
    }

    def @Max
	precedence 36
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigpmax"
			}
			PDF @Yield {
			}
		}
    }

    def @Min
	precedence 36
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigpmin"
			}
			PDF @Yield {
			}
		}
    }

    def @Distance
	precedence 35
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigdistance"
			}
			PDF @Yield {
			}
		}
    }

    def @XDistance
	precedence 35
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigxdistance"
			}
			PDF @Yield {
			}
		}
    }

    def @YDistance
	precedence 35
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigydistance"
			}
			PDF @Yield {
			}
		}
    }

    def @Angle
	precedence 35
	left x
	right y
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				x y "lfigangle"
			}
			PDF @Yield {
			}
		}
    }

    def @Prev
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				"lfigprevious"
			}
			PDF @Yield {
			}
		}
    }

    def "::"
	precedence 33
	left name
	right x
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				{ "currentdict end" maxlabels "dict begin begin"
				  // "("name") lfigpromotelabels" } @Graphic x
			}
			PDF @Yield {
			}
		}
    }

    def @Label
	right name
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				"/"name "lfigpointdef"
			}
			PDF @Yield {
			}
		}
    }

    def @MarkOf
	precedence 32
	left point
	right x
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				{ point "translate" } @InnerGraphic
				{
				    /0io |0io @OneCol @OneRow x |0io /0io
				}
			}
			PDF @Yield {
			}
		}
    }

    def @BaseOf
	precedence 32
	left point
	right x
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				{ point "translate" } @InnerGraphic
				{
				    /0io |0io @OneRow @OneCol {
				    | @OneCol @OneRow x ^/
				    } |0io /0io
				}
			}
			PDF @Yield {
			}
		}
    }

    def @ShowLabels
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				"lfigshowlabels" @Graphic
			}
			PDF @Yield {
			}
		}
    }

    def @Figure
	named shape      {            }
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named arrow      { arrow      }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	named paint      { paint      }
	named margin     { 0c         }
	right x
    {
	    @BackEnd @Case {
	    	PostScript @Yield {
				@HContract @VContract
				{
				    #fill the shape
				    paint @Case
				    {
					nopaint @Yield {}
			
					{ nochange darkblue blue lightblue darkgreen green lightgreen
					  darkred red lightred darkcyan cyan lightcyan darkmagenta
					  magenta lightmagenta darkyellow yellow lightyellow darkgray
					  gray lightgray darkgrey grey lightgrey black white }
					@Yield
					{ "/lfig"paint "[" shape "] gsave lfigpaintpath grestore" }
				    }
			
				    # stroke the path and add any arrowheads
				    linestyle @Case
				    {
					{ solid dashed cdashed dotted noline } @Yield
					{
					    linewidth "setlinewidth" "lfig"linecap "setlinecap"
					    dashlength "/lfig"linestyle "[" shape "] lfigdopath"
					    arrow @Case
					    {
						noarrow @Yield { pop pop }
						{ forward back both } @Yield
						{  dashlength "/lfig"linestyle "/"lfigblack
						   headstyle @Case
						   { { open halfopen closed } @Yield "lfig"headstyle }
						   headlength headwidth "lfig"arrow
						}
					    }
					}
				    }
				}
				@Graphic
				{
				    ^/margin ^|margin @OneCol @OneRow x |margin
				     /margin
				}
			}

			PDF @Yield {
			}
		}
    }

    def @Frame
	right x
    {
	@Figure
	    shape {xsize 0 @Label X 0 ysize @Label Y}
	{ x }
    }

    def @Box
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		# 0     0      @Label SW
		# xsize 0      @Label SE
		# xsize ysize  @Label NE
		# 0     ysize  @Label NW
		# SE ** 0.5    @Label S
		# NW ** 0.5    @Label W
		# W ++ SE      @Label E
		# S ++ NW      @Label N
		# NE ** 0.5    @Label CTR
		# SW SE NE NW SW
		lfigbox
	    }
	    linestyle  { linestyle }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }


    def @CurveBox
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		lfigcurvebox
	    }
	    linestyle  { linestyle }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	{ 0c @HShift x }
    }

    def @ShadowBox
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	named shadow     { 0.2f       }
	right x
    {
		@BackEnd @Case {
			PostScript @Yield {
				@VContract @HContract 0c @HShift "lfigshadow" @Graphic
				{
				  ^/shadow ^|shadow 0c @HShift
				  @Figure
				    shape {
					lfigbox
				    }
				    linestyle  { linestyle }
				    linewidth  { linewidth  }
				    linecap    { linecap    }
				    dashlength { dashlength }
				    paint      { paint      }
				    margin     { margin     }
				  0c @HShift x
				  |shadow /shadow
				}
			}
			PDF @Yield {
				@VContract @HContract 0c @HShift

#				"lfigshadow" @Graphic is this:
				{ "__mul(__xmark, 2) 0 m __xsize 0 l"			#  xmark 2 mul 0 moveto xsize 0 lineto
				  "__xsize __sub(__ysize, __mul(__xmark, 2)) l"	#  xsize ysize xmark 2 mul sub lineto
				  "__sub(__xsize, __xmark) __sub(ysize, __mul(__xmark, 2)) l"	#  xsize xmark sub ysize xmark 2 mul sub lineto
				  "__sub(__xsize, __xmark) __xmark l"			#  xsize xmark sub xmark lineto
				  "__mul(__xmark, 2) __xmark l h f"				#  xmark 2 mul xmark lineto closepath fill
				} @Graphic

				{
				  ^/shadow ^|shadow 0c @HShift
				  @Figure
				    shape {
					lfigbox
				    }
				    linestyle  { linestyle }
				    linewidth  { linewidth  }
				    linecap    { linecap    }
				    dashlength { dashlength }
				    paint      { paint      }
				    margin     { margin     }
				  0c @HShift x
				  |shadow /shadow
				}
			}
		}
    }

    def @Square
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		# {xsize ysize} ** 0.5                           @Label CTR
		# CTR ++ {{xsize xsize} @Max {ysize ysize}}**0.5 @Label NE
		# CTR ++ { {CTR @Distance NE} << 135 }           @Label NW
		# CTR ++ { {CTR @Distance NE} << 225 }           @Label SW
		# CTR ++ { {CTR @Distance NE} << 315 }           @Label SE
		# SW ** 0.5 ++ SE ** 0.5                         @Label S
		# NW ** 0.5 ++ NE ** 0.5                         @Label N
		# SW ** 0.5 ++ NW ** 0.5                         @Label W
		# SE ** 0.5 ++ NE ** 0.5                         @Label E
		# SW SE NE NW SW
		lfigsquare
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }

    def @Diamond
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		# {xsize 0} ** 0.5  @Label S
		# {0 ysize} ** 0.5  @Label W
		# S ++ W            @Label CTR
		# CTR ++ W          @Label N
		# CTR ++ S          @Label E
		# S E N W S
		lfigdiamond
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }

    def @Polygon
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	named sides      { 3          }
	named angle      { "dup 180 exch div" }
	right x
    {
	@Figure
	    shape      { sides angle lfigpolygon }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }

    def @Ellipse
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		# {xsize 0} ** 0.5  @Label S
		# {0 ysize} ** 0.5  @Label W
		# S ++ W            @Label CTR
		# CTR ++ W          @Label N
		# CTR ++ S          @Label E
		# CTR ++ {xsize 0} ** 0.3536 ++ {0 ysize} ** 0.3536  @Label NE
		# CTR ++ {xsize 0} ** 0.3536 -- {0 ysize} ** 0.3536  @Label SE
		# CTR -- {xsize 0} ** 0.3536 ++ {0 ysize} ** 0.3536  @Label NW
		# CTR -- {xsize 0} ** 0.3536 -- {0 ysize} ** 0.3536  @Label SW
		# S [ CTR ] E [ CTR ] N [ CTR ] W [ CTR ] S
		lfigellipse
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }

    def @Circle
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { margin     }
	right x
    {
	@Figure
	    shape {
		# {xsize ysize} **0.5                    @Label CTR
		# CTR ++ {{xsize 0} @Max {ysize 0}}**0.5 @Label E
		# CTR ++ { {CTR @Distance E} << 45  }    @Label NE
		# CTR ++ { {CTR @Distance E} << 90  }    @Label N
		# CTR ++ { {CTR @Distance E} << 135 }    @Label NW
		# CTR ++ { {CTR @Distance E} << 180 }    @Label W
		# CTR ++ { {CTR @Distance E} << 225 }    @Label SW
		# CTR ++ { {CTR @Distance E} << 270 }    @Label S
		# CTR ++ { {CTR @Distance E} << 315 }    @Label SE
		# S [ CTR ] E [ CTR ] N [ CTR ] W [ CTR ] S
		lfigcircle
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	x
    }

    def @HLine
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { arrow      }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		# 0     ymark @Prev @Label FROM
		# xsize ymark @Prev @Label TO
		lfighline
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @VLine
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { arrow      }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		# xmark ysize @Prev @Label FROM
		# xmark 0     @Prev @Label TO
		lfigvline
	    }
	    linestyle  { linestyle }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @HArrow
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { forward    }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		# 0     ymark @Prev @Label FROM
		# xsize ymark @Prev @Label TO
		lfighline
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @VArrow
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { forward    }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		# xmark ysize @Prev @Label FROM
		# xmark 0     @Prev @Label TO
		lfigvline
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @Line
	named from       { 0 ysize    }
	named to         { xsize 0    }
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { arrow      }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		from @Prev @Label FROM
		to   @Prev @Label TO
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @Arrow
	named from       { 0 ysize    }
	named to         { xsize 0    }
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { forward    }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		from @Prev @Label FROM
		to   @Prev @Label TO
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    def @Arc
	named from       { 0 ysize    }
	named to         { xsize 0    }
	named ctr        { 0 0        }
	named direction  { clockwise  }
	named linestyle  { linestyle  }
	named linewidth  { linewidth  }
	named linecap    { linecap    }
	named dashlength { dashlength }
	named paint      { paint      }
	named margin     { 0c         }
	named arrow      { noarrow    }
	named headstyle  { headstyle  }
	named headwidth  { headwidth  }
	named headlength { headlength }
	right x
    {
	@Figure
	    shape {
		from @Label FROM
		to   @Label TO
		ctr  @Label CTR
		FROM [ CTR
		direction @Case { {clockwise anticlockwise} @Yield direction }
		] TO
	    }
	    linestyle  { linestyle  }
	    linewidth  { linewidth  }
	    linecap    { linecap    }
	    dashlength { dashlength }
	    paint      { paint      }
	    margin     { margin     }
	    arrow      { arrow      }
	    headstyle  { headstyle  }
	    headwidth  { headwidth  }
	    headlength { headlength }
	x
    }

    @BackEnd @Case {
        PostScript @Yield {
            { "grestore save gsave" maxlabels "dict begin lfigdict begin"
              // "end end restore"
            } @Graphic @Body
        }
        PDF @Yield {
        }
    }

@End @Fig