--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Ruler.st	Fri Jul 16 11:44:30 1993 +0200
@@ -0,0 +1,209 @@
+"
+ COPYRIGHT (c) 1991-93 by Claus Gittinger
+              All Rights Reserved
+
+ This software is furnished under a license and may be used
+ only in accordance with the terms of that license and with the
+ inclusion of the above copyright notice.   This software may not
+ be provided or otherwise made available to, or used by, any
+ other person.  No title to or ownership of the software is
+ hereby transferred.
+"
+
+View subclass:#Ruler
+         instanceVariableNames:'fgColor metric paperWidth paperHeight'
+         classVariableNames:''
+         poolDictionaries:''
+         category:'Views-Interactors'
+!
+
+Ruler comment:'
+
+COPYRIGHT (c) 1991-93 by Claus Gittinger
+              All Rights Reserved
+
+a Ruler for page layout.
+
+%W% %E%
+
+written oct 91 by claus
+'!
+
+!Ruler methodsFor:'accessing'!
+
+metric:aSymbol
+    "set the metric"
+
+    metric := aSymbol.
+    shown ifTrue:[
+        self redraw
+    ]
+! !
+
+!Ruler methodsFor:'redrawing'!
+
+redraw
+    "redraw scale"
+
+    |x pixelPerMM pixelPerInch mod pos shortLen veryShortLen longLen charY
+     top paperWidthMM paperWidthPixel|
+
+    self fill:viewBackground.
+
+    paperWidthPixel := (self inchToPixel:paperWidth) rounded.
+    (width > paperWidthPixel) ifTrue:[
+        self paint:(Color darkGrey).
+        self fillRectangleX:paperWidthPixel y:0
+                      width:(width - paperWidthPixel) height:height.
+        self paint:fgColor.
+        self displayLineFromX:paperWidthPixel y:0
+                          toX:paperWidthPixel y:height
+    ].
+
+    self paint:fgColor.
+
+    top := height - font height - font ascent.
+    longLen := font height.
+    shortLen := longLen // 2.
+    charY := top + (font ascent) + shortLen.
+    mod := 1.
+
+    (metric == #mm) ifTrue:[
+        "centimeter - long blibs every centimeter; short ones every half"
+
+        paperWidthMM := self inchToMillimeter:paperWidth.
+        pixelPerMM := self millimeterToPixel:1.
+        pos := 5.
+        x := (pixelPerMM * pos) rounded.
+        self displayString:'cm' x:3 y:charY.
+        [(x < width) and:[pos <= paperWidthMM]] whileTrue:[
+            (mod == 1) ifTrue:[
+                self displayLineFromX:x y:top
+                                  toX:x y:(top + shortLen)
+            ] ifFalse:[
+                self displayLineFromX:x y:top
+                                  toX:x y:(top + longLen).
+                self displayString:(pos // 10) asInteger printString
+                                 x:(x + 3)
+                                 y:charY
+            ].
+            mod := (mod + 1) \\ 2.
+            pos := pos + 5.
+            x := (pixelPerMM * pos) rounded 
+        ]
+    ].
+    (metric == #inch) ifTrue:[
+        "inches - long blibs every inch; short ones every half; very
+         short ones every quarter"
+
+        pixelPerInch := self inchToPixel:1.
+        pos := 0.25.
+        x := (pixelPerInch * pos) rounded.
+        veryShortLen := longLen // 4.
+        self displayString:'inch' x:3 y:charY.
+        [(x < width) and:[pos <= paperWidth]] whileTrue:[
+            (mod == 0) ifTrue:[
+                self displayLineFromX:x y:top
+                                  toX:x y:(top + longLen).
+                self displayString:pos asInteger printString
+                                 x:(x + 3)
+                                 y:charY
+            ] ifFalse:[
+                (mod == 2) ifTrue:[
+                    self displayLineFromX:x y:top
+                                      toX:x y:(top + shortLen)
+                ] ifFalse:[
+                    self displayLineFromX:x y:top
+                                      toX:x y:(top + veryShortLen)
+                ]
+            ].
+            mod := (mod + 1) \\ 4.
+            pos := pos + 0.25.
+            x := (pixelPerInch * pos) rounded
+        ]
+    ].
+    self redrawEdges
+! !
+
+!Ruler methodsFor:'initialization'!
+
+initialize
+    super initialize.
+
+    fgColor := Black.
+    self height:(font height + font descent + font descent). 
+    (Language == #english) ifTrue:[
+        metric := #inch
+    ] ifFalse:[
+        metric := #mm
+    ].
+    paperWidth := 8.5.
+    paperHeight := 11
+
+    "Ruler new realize"
+! !
+
+!Ruler methodsFor:'metric conversions'!
+
+inchToMillimeter:inches
+    "convert inches to mm"
+
+    ^ inches * 25.4
+!
+
+inchToPixel:inches
+    "convert inches to screen pixels"
+
+    ^ inches * self horizontalPixelPerInch
+!
+
+inchToTwip:inches
+    "convert inches to twips"
+
+    ^ inches * 1440
+
+!
+
+millimeterToPixel:mm
+    "convert mms to screen pixels"
+
+    ^ mm * self horizontalPixelPerMillimeter
+
+!
+
+millimeterToInch:mm
+    "convert mm to inches"
+
+    ^ mm / 25.4
+!
+
+pointToTwip:points
+    "convert points to twips"
+
+    ^ points * 20
+!
+
+twipToInch:twips
+    "convert twips to inches"
+
+    ^ twips / 1440.0
+!
+
+pixelToInch:pixels
+    "convert pixels to inches"
+
+    ^ pixels / self horizontalPixelPerInch
+!
+
+twipToPixel:twips
+    "convert twips to screen pixels"
+
+    ^ (twips / 1440.0) * self horizontalPixelPerInch
+
+!
+
+twipToPoint:twips
+    "convert twips to points"
+
+    ^ twips / 20.0
+! !