diff -r ed41e1bbd9a1 -r e23465aad9e8 Scroller.st
--- a/Scroller.st	Fri Mar 01 19:44:55 1996 +0100
+++ b/Scroller.st	Fri Mar 01 19:48:00 1996 +0100
@@ -54,11 +54,6 @@
     When moved, either a predefined action is performed (scrollAction),
     or a model is informed via the changeMsg (which is #value: by default).
 
-    Beside the obvious 3D rectangle, a scroller may draw a know-form
-    (as in NeXT) or little tally marks (as on SGI) in itself.
-    These are controlled by the shadowForm, lightForm, tallyLevel and tallyMarks
-    instance variables.
-
     The scroller can work synchronous (i.e. every move leads to an immediate evaluation
     of the action, or asynchronous (i.e. perform action on end-of move).
     By default, scrollers are synchronous. Asynchronous operation makes sense, 
@@ -68,6 +63,20 @@
     and as an abstract superclass for horizontalScrollers, sliders and
     miniScrollers.
 
+  range:
+    the value passed to the model or via the action blocks is scaled according
+    to the min/maxRange instance variables.
+    These default to 0..100 for percentage values.
+    It does not make sense to change the range for scrollbar-scrollers,
+    but may be useful with Sliders or in special applications.
+
+  style stuff:
+
+    Beside the obvious 3D rectangle, a scroller may draw a know-form
+    (as in NeXT) or little tally marks (as on SGI) in itself.
+    These are controlled by the shadowForm, lightForm, tallyLevel and tallyMarks
+    instance variables.
+
   Instance variables:
 
     thumbOrigin                 <Number>        origin of thumb (in percent)
@@ -75,14 +84,14 @@
     thumbColor                  <Color>         color of thumb
     thumbFrameColor             <Color>         color of the frame around the thumb
     scrollAction                <Block>         1 arg block to be evaluated when scrolled
-						(arg is position in percent)
+                                                (arg is position in percent)
     orientation                 <Symbol>        #horizontal or #vertical
     thumbFrame                  <Rectangle>     frame of thumb in pixels (cached)
     thumbLevel                  <Number>        level of thumb if 3d
     scrolling                   <Boolean>       true during scroll
     pressOffset                 <Number>        temporary (offset into frame when move started)
     synchronousOperation        <Boolean>       true if synchronous (i.e. dont wait till release
-						to perform action)
+                                                to perform action)
     shadowForm                  <Form>          bitmap of knob if any (shadow part)
     lightForm                   <Form>          bitmap of knob if any (light part)
     inset                       <Integer>       number of pixels to inset thumb from view borders
@@ -92,10 +101,10 @@
     thumbHalfShadowColor        <Color>         used to draw smooth edges
     thumbHalfLightColor         <Color>         used to draw smooth edges
     thumbFrameSizeDifference    <Integer>       number of pixels the thumb is larger than 
-						it should be (can be negative for mswin-style)
+                                                it should be (can be negative for mswin-style)
     tallyLevel                  <Integer>       if not zero, specifies if tally-marks should
-						go into or out of the display (actually only <0/>0 is checked)
-						I dont know of a better word for these ...
+                                                go into or out of the display (actually only <0/>0 is checked)
+                                                I dont know of a better word for these ...
     tallyMarks                  <Integer>       number of tally marks
     fixThumbHeight              <Boolean>       perform 'wrong' height computation a la mswindows
     rangeStart                  <Number>        the range of the scroller
@@ -137,102 +146,116 @@
 "
     basic scroller setup:
 
-	|top s|
+        |top s|
 
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(20@1.0).
-	s thumbHeight:10.  'percent'.     
-	top open
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:10.  'percent'.     
+        top open
 
 
     setting its thumb-height:
-	|top s|
+        |top s|
 
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(20@1.0).
-	s thumbHeight:50.  'percent'.     
-	top open
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:50.  'percent'.     
+        top open
 
 
     setting its thumb-origin:
-	|top s|
+        |top s|
 
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(20@1.0).
-	s thumbHeight:10.  'percent'.     
-	s thumbOrigin:30.  'percent'.     
-	top open
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:10.  'percent'.     
+        s thumbOrigin:30.  'percent'.     
+        top open
 
 
     a scroller with action block (ST/X style):
 
-	|top s|
+        |top s|
+
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:10.  'percent'.     
+        s scrollAction:[:percent | Transcript show:'moved to: '; showCr:percent asFloat].
+        top open
+
 
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(20@1.0).
-	s thumbHeight:10.  'percent'.     
-	s scrollAction:[:percent | Transcript show:'moved to: '; showCr:percent asFloat].
-	top open
+    setting its range:
+
+        |top s|
+
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:10.  'percent'.     
+        s scrollAction:[:percent | Transcript show:'moved to: '; showCr:percent asFloat].
+        s start:0 stop:1.
+        top open
 
 
     create a scroller in its default extent and have it positioned
-    at the right; beside another view:
+    at the side; beside another view:
 
-	|top s v|
+        |top s v|
 
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(0.0@1.0).
-	s rightInset:(s preferredExtent x negated).
-	s thumbHeight:10.
-	s level:1.
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(0.0@1.0).
+        s rightInset:(s preferredExtent x negated).
+        s thumbHeight:10.
+        s level:1.
 
-	v := View in:top.
-	v origin:0.0@0.0 corner:1.0@1.0.
-	v leftInset:(s preferredExtent x).
-	v viewBackground:Color red.
-	v level:2.
+        v := View in:top.
+        v origin:0.0@0.0 corner:1.0@1.0.
+        v leftInset:(s preferredExtent x).
+        v viewBackground:Color red.
+        v level:2.
 
-	top open
+        top open
 
 
     using a model (ST-80 style):
 
-	|top s m|
+        |top s m|
+
+        m := 0 asValue.
+        InspectorView openOn:m monitor:'value'.  'look at value'.
 
-	m := 0 asValue.
-	m inspect. 'look at value'.
-	top := StandardSystemView new extent:200@200.
-	s := Scroller in:top.
-	s origin:(0.0@0.0) corner:(20@1.0).
-	s thumbHeight:10.  'percent'.     
-	s model:m.
-	top open
+        top := StandardSystemView new extent:200@200.
+        s := Scroller in:top.
+        s origin:(0.0@0.0) corner:(20@1.0).
+        s thumbHeight:10.  'percent'.     
+        s model:m.
+        top open
 
 
     using a different changeSelector:
 
-	|top s1 s2 m|
+        |top s1 s2 m|
 
-	m := Plug new.
-	m respondTo:#value1: with:[:v | Transcript show:'scroller 1 moved to: '; showCr:v].
-	m respondTo:#value2: with:[:v | Transcript show:'scroller 2 moved to: '; showCr:v].
+        m := Plug new.
+        m respondTo:#value1: with:[:v | Transcript show:'scroller 1 moved to: '; showCr:v].
+        m respondTo:#value2: with:[:v | Transcript show:'scroller 2 moved to: '; showCr:v].
 
-	top := StandardSystemView new extent:200@200.
-	s1 := Scroller in:top.
-	s1 origin:(0.0@0.0) corner:(20@1.0).
-	s1 thumbHeight:10.  'percent'.     
-	s1 model:m; change:#value1:.
+        top := StandardSystemView new extent:200@200.
+        s1 := Scroller in:top.
+        s1 origin:(0.0@0.0) corner:(20@1.0).
+        s1 thumbHeight:10.  'percent'.     
+        s1 model:m; change:#value1:.
 
-	s2 := Scroller in:top.
-	s2 origin:(30@0.0) corner:(50@1.0).
-	s2 thumbHeight:10.  'percent'.     
-	s2 model:m; change:#value2:.
-	top open
+        s2 := Scroller in:top.
+        s2 origin:(30@0.0) corner:(50@1.0).
+        s2 thumbHeight:10.  'percent'.     
+        s2 model:m; change:#value2:.
+        top open
 "
 ! !
 
@@ -352,17 +375,180 @@
     "Modified: 1.3.1996 / 19:12:10 / cg"
 !
 
-start:start
-    "set the scrollers range start"
+or may be not available for the copy
+		    "
+		    (orientation == #vertical) ifTrue:[
+			self drawThumbBackgroundInX:thumbLeft y:oldTop
+					      width:tW height:(height - oldTop).
+		    ] ifFalse:[
+			self drawThumbBackgroundInX:oldLeft y:thumbTop
+					      width:(width - oldLeft) height:tH.
+		    ].
+		    self drawThumb.
+		    ^ self
+		].
+
+		self catchExpose.
+		"
+		 copy the thumbs pixels
+		"
+		(orientation == #vertical) ifTrue:[
+		    self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
 
-    rangeStart := start.
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
 !
 
-start:start stop:stop
+ifTrue:[
+			self drawThumbBackgroundInX:thumbLeft y:oldTop
+					      width:tW height:(height - oldTop).
+		    ] ifFalse:[
+			self drawThumbBackgroundInX:oldLeft y:thumbTop
+					      width:(width - oldLeft) height:tH.
+		    ].
+		    self drawThumb.
+		    ^ self
+		].
+
+		self catchExpose.
+		"
+		 copy the thumbs pixels
+		"
+		(orientation == #vertical) ifTrue:[
+		    self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
+
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
+!
+
+start:start stop:stop step:step
     "set the scrollers range"
 
     rangeStart := start.
-    rangeEnd := stop
+    rangeEnd := stop.
+    rangeStep := step.
+
+    "Created: 1.3.1996 / 19:39:18 / cg"
 !
 
 step
@@ -373,10 +559,82 @@
     "Modified: 1.3.1996 / 19:12:16 / cg"
 !
 
-step:step
-    "set the scrollers range step"
+:thumbTop
+					      width:(width - oldLeft) height:tH.
+		    ].
+		    self drawThumb.
+		    ^ self
+		].
+
+		self catchExpose.
+		"
+		 copy the thumbs pixels
+		"
+		(orientation == #vertical) ifTrue:[
+		    self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
 
-    rangeStep := step
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
 !
 
 stop
@@ -387,19 +645,114 @@
     "Modified: 1.3.1996 / 19:12:20 / cg"
 !
 
-stop:stop
-    "set the scrollers range stop"
+copy the thumbs pixels
+		"
+		(orientation == #vertical) ifTrue:[
+		    self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
 
-    rangeEnd := stop
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
 !
 
-thumbFrame
-    "return the area used by the thumbFrame (in device coordinates).
-     Allows access to the thumbs physical screen position, for
-     example to position a label below (see Slider-Examples)"
-
-    thumbFrame isNil ifTrue:[ self computeThumbFrame].
-    ^ thumbFrame
+umbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
 !
 
 thumbHeight
@@ -410,47 +763,23 @@
     "Modified: 1.3.1996 / 19:12:28 / cg"
 !
 
-thumbHeight:aNumber 
-    "set the thumbs height (in percent by default)"
-
-    |newHeight realNewHeight oldFrame nBg|
-
-    newHeight := aNumber / (rangeEnd - rangeStart / 100).
-
-    (newHeight > 100) ifTrue:[
-	realNewHeight := 100
-    ] ifFalse:[
-	realNewHeight := newHeight
-    ].
-    ((realNewHeight ~= thumbHeight) or:[thumbFrame isNil]) ifTrue:[
-	thumbHeight := realNewHeight.
-
-	(DefaultFullViewBackground notNil
-	and:[DefaultViewBackground notNil
-	and:[DefaultFullViewBackground ~~ DefaultViewBackground]]) ifTrue:[
-	    realNewHeight >= 100 ifTrue:[
-		nBg := DefaultFullViewBackground.
-	    ] ifFalse:[
-		nBg := DefaultViewBackground
-	    ].
-	    nBg := nBg on:device.
-	    nBg ~~ viewBackground ifTrue:[
-		self viewBackground:nBg.
-		shown ifTrue:[self clear].
-	    ]
-	].
-
-	shown ifTrue:[
-	    oldFrame := thumbFrame.
-	    self computeThumbFrame.
-	    (fixThumbHeight or:[oldFrame ~~ thumbFrame]) ifTrue:[
-		oldFrame notNil ifTrue:[
-		    self drawThumbBackgroundInX:(oldFrame left)
-					      y:(oldFrame top) 
-					  width:(oldFrame width) 
-					 height:(oldFrame height).
+[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
 		].
-		self drawThumb
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
 	    ]
 	] ifFalse:[
 	    thumbFrame := nil
@@ -466,10 +795,1155 @@
     "Modified: 1.3.1996 / 19:12:37 / cg"
 !
 
-thumbOrigin:aNumber 
-    "set the thumbs origin (in percent by default)"
+old ~~ new.
+	changed ifFalse:[
+	    old := self absFromPercent:thumbHeight.
+	    new := self absFromPercent:realNewHeight.
+	    changed := (old ~~ new)
+	].
+	(changed or:[thumbFrame isNil]) ifTrue:[
+	    thumbOrigin := realNewOrigin.
+	    thumbHeight := realNewHeight.
+
+	    (DefaultFullViewBackground notNil
+	    and:[DefaultViewBackground notNil
+	    and:[DefaultFullViewBackground ~~ DefaultViewBackground]]) ifTrue:[
+		realNewHeight >= 100 ifTrue:[
+		    nBg := DefaultFullViewBackground.
+		] ifFalse:[
+		    nBg := DefaultViewBackground
+		].
+		nBg := nBg on:device.
+		nBg ~~ viewBackground ifTrue:[
+		    self viewBackground:nBg.
+		    shown ifTrue:[self clear].
+		]
+	    ].
+
+	    shown ifTrue:[
+		thumbFrame notNil ifTrue:[
+		    self drawThumbBackgroundInX:(thumbFrame left)
+					      y:(thumbFrame top) 
+					  width:(thumbFrame width) 
+					 height:(thumbFrame height).
+		].
+		self computeThumbFrame.
+		self drawThumb
+	    ] ifFalse:[
+		thumbFrame := nil
+	    ]
+	]
+    ]
+!
+
+humbColor.
+    self fillRectangleX:l y:t width:w-1 height:h.
+
+    thumbLevel == 0 ifTrue:[
+	thumbFrameColor notNil ifTrue:[
+	    self paint:thumbFrameColor.
+	    self displayRectangle:thumbFrame.
+	].
+	^ self
+    ].
+
+    "what a kludge - must be a parameter to drawEdge..."
+    self drawEdgesForX:l y:t width:w height:h level:thumbLevel
+		shadow:thumbShadowColor light:thumbLightColor
+		halfShadow:thumbHalfShadowColor halfLight:thumbHalfLightColor
+		style:thumbEdgeStyle.
+
+    thumbFrameColor notNil ifTrue:[
+	self paint:thumbFrameColor.
+	orientation == #vertical ifTrue:[
+	    self displayRectangleX:l y:t width:w"-1" height:h.
+	] ifFalse:[
+	    self displayRectangleX:l y:t width:w height:h"-1".
+	]
+    ].
+
+    (tallyLevel == 0 or:[tallyMarks == 0]) ifTrue:[
+	shadowForm notNil ifTrue:[
+	    handleX := l + ((w - 8) // 2).
+	    handleY := t + ((h - 8) // 2).
+	    self drawHandleFormAtX:handleX y:handleY
+	].
+	^ self
+    ].
+
+    "iris style - draw tallys"
+
+    tallyLevel > 0 ifTrue:[
+	color1 := thumbLightColor.
+	color2 := thumbShadowColor.
+    ] ifFalse:[
+	color1 := thumbShadowColor.
+	color2 := thumbLightColor.
+    ].
+
+    "draw tally marks"
+
+    (orientation == #vertical) ifTrue:[
+	self paint:color1.
+	y := t + (h // 2) - 1.
+	xL := l + thumbLevel - 1.
+	xR := l + w - thumbLevel "+ 1".
+	self displayLineFromX:xL y:y toX:xR y:y.
+	y := y + 1.
+	self paint:color2.
+	self displayLineFromX:xL y:y toX:xR y:y.
+
+	tallyMarks > 1 ifTrue:[
+	    "dont draw other marks if there is not enough space"
+
+	    mm := device verticalPixelPerMillimeter rounded.
+	    h > (mm * (tallyMarks * 2)) ifTrue:[
+		y := y - 1 - mm.
+		self paint:color1.
+		self displayLineFromX:xL y:y toX:xR y:y.
+		y := y + 1.
+		self paint:color2.
+		self displayLineFromX:xL y:y toX:xR y:y.
+
+		y := y - 1 + mm + mm.
+		self paint:color1.
+		self displayLineFromX:xL y:y toX:xR y:y.
+		y := y + 1.
+		self paint:color2.
+		self displayLineFromX:xL y:y toX:xR y:y
+	    ]
+	]
+    ] ifFalse:[
+	x := l + (w // 2) - 1.
+	yT := t + thumbLevel - 1.
+	yB := t + h - thumbLevel "+ 1".
+	self paint:color1.
+	self displayLineFromX:x y:yT toX:x y:yB.
+	self paint:color2.
+	x := x + 1.
+	self displayLineFromX:x y:yT toX:x y:yB.
+
+	tallyMarks > 1 ifTrue:[
+	    "dont draw other marks if there is not enough space"
+
+	    mm := device horizontalPixelPerMillimeter rounded.
+	    w > (mm * (tallyMarks * 2)) ifTrue:[
+		x := x - 1 - mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB.
+
+		x := x - 1 + mm + mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB
+	    ]
+	]
+    ]
+! !
+
+!Scroller methodsFor:'accessing-behavior'!
+
+start 
+    "return the scrollers range min"
+
+    ^ rangeStart
+
+    "Modified: 1.3.1996 / 19:12:10 / cg"
+!
+
+g"
+!
+
+return the scrollers range max"
+
+    ^ rangeEnd
+
+    "Modified: 1.3.1996 / 19:12:20 / cg"
+!
+
+/ 19:12:20 / cg"
+!
+
+a used by the thumbFrame (in device coordinates).
+     Allows access to the thumbs physical screen position, for
+     example to position a label below (see Slider-Examples)"
+
+    thumbFrame isNil ifTrue:[ self computeThumbFrame].
+    ^ thumbFrame
+!
+
+example to position a label below (see Slider-Examples)"
+
+    thumbFrame isNil ifTrue:[ self computeThumbFrame].
+    ^ thumbFrame
+!
+
+self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
+
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
+! !
+
+!Scroller methodsFor:'accessing-look'!
+
+return the scrollers range step"
+
+    ^ rangeStep
+
+    "Modified: 1.3.1996 / 19:12:16 / cg"
+!
+
+/ 19:12:16 / cg"
+!
+
+toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
+
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
+!
+
+.
+
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
+	] ifFalse:[
+	    thumbFrame := nil
+	]
+    ]
+! !
+
+!Scroller methodsFor:'drawing'!
+
+self displayLineFromX:xL y:y toX:xR y:y
+	    ]
+	]
+    ] ifFalse:[
+	x := l + (w // 2) - 1.
+	yT := t + thumbLevel - 1.
+	yB := t + h - thumbLevel "+ 1".
+	self paint:color1.
+	self displayLineFromX:x y:yT toX:x y:yB.
+	self paint:color2.
+	x := x + 1.
+	self displayLineFromX:x y:yT toX:x y:yB.
+
+	tallyMarks > 1 ifTrue:[
+	    "dont draw other marks if there is not enough space"
+
+	    mm := device horizontalPixelPerMillimeter rounded.
+	    w > (mm * (tallyMarks * 2)) ifTrue:[
+		x := x - 1 - mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB.
+
+		x := x - 1 + mm + mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB
+	    ]
+	]
+    ]
+!
+
+T toX:x y:yB.
+
+	tallyMarks > 1 ifTrue:[
+	    "dont draw other marks if there is not enough space"
+
+	    mm := device horizontalPixelPerMillimeter rounded.
+	    w > (mm * (tallyMarks * 2)) ifTrue:[
+		x := x - 1 - mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB.
+
+		x := x - 1 + mm + mm.
+		self paint:color1.
+		self displayLineFromX:x y:yT toX:x y:yB.
+		x := x + 1.
+		self paint:color2.
+		self displayLineFromX:x y:yT toX:x y:yB
+	    ]
+	]
+    ]
+!
+
+roll
+     action is now performed"
+
+    |rect|
+
+    scrolling ifTrue:[
+        thumbFrame notNil ifTrue:[
+            frameBeforeMove notNil ifTrue:[
+                rect := frameBeforeMove.
+                frameBeforeMove := nil.
+                self drawThumbBackgroundInX:rect left
+                                          y:rect top
+                                      width:rect width 
+                                     height:rect height.
+                (rect intersects:thumbFrame) ifTrue:[
+                    self drawThumb
+                ]
+            ].
+
+            scrolling := false.
+            synchronousOperation ifFalse: [
+                self tellOthers.
+            ]
+        ]
+    ]
+
+    "Modified: 23.12.1995 / 12:42:25 / cg"
+! !
+
+!Scroller methodsFor:'event handling'!
+
+l) ifTrue:[
+	curr := y.
+	curr2 := y - (thumbFrame height // 2).
+	limit1 := height.
+	limit2 := thumbFrame top
+    ] ifFalse:[
+	curr := x.
+	curr2 := x - (thumbFrame width // 2).
+	limit1 := width.
+	limit2 := thumbFrame left
+    ].
+
+    (curr2 < 0) ifTrue:[                        "check against limits"
+	pos := 0
+    ] ifFalse:[
+	(curr2 > limit1) ifTrue:[
+	    pos := limit1
+	] ifFalse:[
+	    pos := curr2
+	]
+    ].
+
+    frameBeforeMove := thumbFrame insetBy:1@1.
+
+    self thumbOrigin:(self percentFromAbs:pos).
+    self tellOthers.
+
+    (orientation == #vertical) ifTrue:[
+	limit2 := thumbFrame top
+    ] ifFalse:[
+	limit2 := thumbFrame left
+    ].
+    pressOffset := curr - limit2.
+    scrolling := true
+!
+
+self
+	].
+	((y + h) < thumbFrame top) ifTrue:[
+	    ^ self
+	].
+	self drawThumb
+    ]
+!
+
+humb
+    ]
+!
+
+ght"
+
+    self thumbOrigin:(thumbOrigin + thumbHeight).
+    self tellOthers
+!
+
+].
+    DefaultShadowColor notNil ifTrue:[
+	shadowColor := DefaultShadowColor on:device.
+    ].
+    DefaultLightColor notNil ifTrue:[
+	lightColor := DefaultLightColor on:device.
+    ].
+
+    tallyMarks := DefaultTallyMarks.
+    tallyLevel := DefaultTallyLevel.
+    DefaultLevel ~~ level ifTrue:[
+	self level:DefaultLevel.
+    ].
+    DefaultBorderWidth ~~ borderWidth ifTrue:[
+	self borderWidth:DefaultBorderWidth.
+    ].
+    thumbLevel := DefaultThumbLevel.
+    inset := DefaultInset.
+    fixThumbHeight := DefaultFixThumbHeight.
+    thumbEdgeStyle := DefaultEdgeStyle.
+
+    DefaultGhostColor notNil ifTrue:[
+	ghostColor := DefaultGhostColor on:device.
+    ].
+    DefaultGhostFrameColor notNil ifTrue:[
+	ghostFrameColor := DefaultGhostFrameColor on:device.
+    ].
+    ghostLevel := DefaultGhostLevel.
 
-    |newOrigin realNewOrigin 
+    DefaultThumbFrameColor notNil ifTrue:[
+	thumbFrameColor := DefaultThumbFrameColor on:device.
+    ].
+    DefaultThumbShadowColor notNil ifTrue:[
+	thumbShadowColor := DefaultThumbShadowColor
+    ] ifFalse:[
+	thumbShadowColor := shadowColor.
+    ].
+    DefaultThumbLightColor notNil ifTrue:[
+	thumbLightColor := DefaultThumbLightColor
+    ] ifFalse:[
+	thumbLightColor := lightColor.
+    ].
+
+    thumbEdgeStyle notNil ifTrue:[
+	DefaultThumbHalfShadowColor notNil ifTrue:[
+	    thumbHalfShadowColor := DefaultThumbHalfShadowColor
+	].
+	DefaultThumbHalfLightColor notNil ifTrue:[
+	    thumbHalfLightColor := DefaultThumbHalfLightColor
+	].
+    ].
+
+    device hasGreyscales ifFalse:[
+	thumbEdgeStyle notNil ifTrue:[
+	    thumbHalfShadowColor := Color darkGrey.
+	    thumbHalfLightColor := White
+	].
+
+	thumbShadowColor := Black.
+"/        thumbLightColor := White.
+
+	styleSheet name = #motif ifTrue:[
+	    DefaultThumbColor isNil ifTrue:[
+		thumbColor := White .
+	    ].
+	]
+    ].
+
+    DefaultThumbColor notNil ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+mbFrameColor := DefaultThumbFrameColor on:device.
+    ].
+    DefaultThumbShadowColor notNil ifTrue:[
+	thumbShadowColor := DefaultThumbShadowColor
+    ] ifFalse:[
+	thumbShadowColor := shadowColor.
+    ].
+    DefaultThumbLightColor notNil ifTrue:[
+	thumbLightColor := DefaultThumbLightColor
+    ] ifFalse:[
+	thumbLightColor := lightColor.
+    ].
+
+    thumbEdgeStyle notNil ifTrue:[
+	DefaultThumbHalfShadowColor notNil ifTrue:[
+	    thumbHalfShadowColor := DefaultThumbHalfShadowColor
+	].
+	DefaultThumbHalfLightColor notNil ifTrue:[
+	    thumbHalfLightColor := DefaultThumbHalfLightColor
+	].
+    ].
+
+    device hasGreyscales ifFalse:[
+	thumbEdgeStyle notNil ifTrue:[
+	    thumbHalfShadowColor := Color darkGrey.
+	    thumbHalfLightColor := White
+	].
+
+	thumbShadowColor := Black.
+"/        thumbLightColor := White.
+
+	styleSheet name = #motif ifTrue:[
+	    DefaultThumbColor isNil ifTrue:[
+		thumbColor := White .
+	    ].
+	]
+    ].
+
+    DefaultThumbColor notNil ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+rue:[
+	thumbShadowColor := DefaultThumbShadowColor
+    ] ifFalse:[
+	thumbShadowColor := shadowColor.
+    ].
+    DefaultThumbLightColor notNil ifTrue:[
+	thumbLightColor := DefaultThumbLightColor
+    ] ifFalse:[
+	thumbLightColor := lightColor.
+    ].
+
+    thumbEdgeStyle notNil ifTrue:[
+	DefaultThumbHalfShadowColor notNil ifTrue:[
+	    thumbHalfShadowColor := DefaultThumbHalfShadowColor
+	].
+	DefaultThumbHalfLightColor notNil ifTrue:[
+	    thumbHalfLightColor := DefaultThumbHalfLightColor
+	].
+    ].
+
+    device hasGreyscales ifFalse:[
+	thumbEdgeStyle notNil ifTrue:[
+	    thumbHalfShadowColor := Color darkGrey.
+	    thumbHalfLightColor := White
+	].
+
+	thumbShadowColor := Black.
+"/        thumbLightColor := White.
+
+	styleSheet name = #motif ifTrue:[
+	    DefaultThumbColor isNil ifTrue:[
+		thumbColor := White .
+	    ].
+	]
+    ].
+
+    DefaultThumbColor notNil ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+:[
+	DefaultThumbHalfShadowColor notNil ifTrue:[
+	    thumbHalfShadowColor := DefaultThumbHalfShadowColor
+	].
+	DefaultThumbHalfLightColor notNil ifTrue:[
+	    thumbHalfLightColor := DefaultThumbHalfLightColor
+	].
+    ].
+
+    device hasGreyscales ifFalse:[
+	thumbEdgeStyle notNil ifTrue:[
+	    thumbHalfShadowColor := Color darkGrey.
+	    thumbHalfLightColor := White
+	].
+
+	thumbShadowColor := Black.
+"/        thumbLightColor := White.
+
+	styleSheet name = #motif ifTrue:[
+	    DefaultThumbColor isNil ifTrue:[
+		thumbColor := White .
+	    ].
+	]
+    ].
+
+    DefaultThumbColor notNil ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+thumbEdgeStyle notNil ifTrue:[
+	    thumbHalfShadowColor := Color darkGrey.
+	    thumbHalfLightColor := White
+	].
+
+	thumbShadowColor := Black.
+"/        thumbLightColor := White.
+
+	styleSheet name = #motif ifTrue:[
+	    DefaultThumbColor isNil ifTrue:[
+		thumbColor := White .
+	    ].
+	]
+    ].
+
+    DefaultThumbColor notNil ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+! !
+
+!Scroller methodsFor:'forced scroll'!
+
+il ifTrue:[
+	thumbColor := DefaultThumbColor on:device
+    ] ifFalse:[
+	thumbColor := White.
+	styleSheet name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+name ~= #normal ifTrue:[
+	    device hasGreyscales ifFalse:[
+		thumbColor := Color grey
+	    ].
+	].
+    ].
+
+    thumbColor := thumbColor on:device.
+    thumbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+! !
+
+!Scroller methodsFor:'forwarding changed origin'!
+
+humbShadowColor notNil ifTrue:[
+	thumbShadowColor := thumbShadowColor on:device.
+    ].
+    thumbLightColor notNil ifTrue:[
+	thumbLightColor := thumbLightColor on:device.
+    ].
+    thumbHalfShadowColor notNil ifTrue:[
+	thumbHalfShadowColor := thumbHalfShadowColor on:device.
+    ].
+    thumbHalfLightColor notNil ifTrue:[
+	thumbHalfLightColor := thumbHalfLightColor on:device.
+    ].
+    thumbEdgeStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+! !
+
+!Scroller methodsFor:'initialization'!
+
+defaultExtent
+    "compute my extent from sub-components"
+
+    ^ self preferredExtent
+
+    "Created: 1.3.1996 / 19:22:21 / cg"
+!
+
+eStyle notNil ifTrue:[
+	thumbHalfShadowColor isNil ifTrue:[
+	    thumbHalfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+alfShadowColor := thumbShadowColor lightened on:device
+	]
+    ].
+
+    styleSheet name = #next ifTrue:[
+	shadowForm := self class handleShadowFormOn:device.
+	lightForm := self class handleLightFormOn:device
+    ] ifFalse:[
+	shadowForm := lightForm := nil
+    ].
+
+    drawableId notNil ifTrue:[
+	self computeThumbFrame
+    ]
+!
+
+initialize
+    "initialize - setup instvars from defaults"
+
+    super initialize.
+    orientation := #vertical.
+
+    scrolling := false.
+    synchronousOperation := true.
+
+    thumbOrigin := 0.
+    thumbHeight := 100.
+    thumbFrameSizeDifference := 0.
+
+    rangeStart := 0.
+    rangeEnd := 100.
+    rangeStep := nil.   "/ meaning: arbitrary precision
+"/    inset := 1.
+
+"/    self computeThumbFrame
+
+    "Modified: 1.3.1996 / 19:22:51 / cg"
+!
+
+ame left) ifTrue:[
+	    (nh == thumbFrame height) ifTrue:[
+	      (nw == thumbFrame width) ifTrue:[ ^ self]
+	    ]
+	  ]
+	]
+    ].
+    thumbFrame := Rectangle left:nx top:ny width:nw height:nh
+! !
+
+!Scroller methodsFor:'private'!
+
+thumbFrame := Rectangle left:nx top:ny width:nw height:nh
+!
+
+ases, this happens ...
+	val := 0
+    ] ifFalse:[
+	val := absValue / t * (rangeEnd - rangeStart).
+    ].
+    val := val + rangeStart.
+
+    val < rangeStart ifTrue:[^ rangeStart].
+    val > rangeEnd ifTrue:[^ rangeEnd].
+    ^ val
+
+!
+
+(orientation == #vertical) ifTrue:[aView innerHeight]
+					   ifFalse:[aView innerWidth].
+	percent := viewsSize * 100.0 / total
+    ].
+    self thumbHeight:percent
+! !
+
+!Scroller methodsFor:'private-scrollView interface'!
+
+^ thumbFrame
+!
+
+wOrigin realNewOrigin 
      oldFrame oldTop oldBot oldLeft oldRight
      thumbTop thumbBot thumbLeft thumbRight
      tH "{ Class: SmallInteger }"
@@ -611,957 +2085,126 @@
     ]
 !
 
-thumbOrigin:originNumber thumbHeight:heightNumber
-    "set both thumbs height and origin (in percent by default)"
-
-    |newHeight newOrigin realNewOrigin realNewHeight old new changed nBg|
-
-    newOrigin := originNumber - rangeStart / (rangeEnd - rangeStart / 100).
-    newHeight := heightNumber / (rangeEnd - rangeStart / 100).
-
-    (newHeight > 100) ifTrue:[
-	realNewHeight := 100
-    ] ifFalse:[
-	realNewHeight := newHeight
-    ].
-    ((newOrigin + realNewHeight) > 100) ifTrue:[
-	realNewOrigin := 100 - realNewHeight
-    ] ifFalse: [
-	realNewOrigin := newOrigin
-    ].
-    (realNewOrigin < 0) ifTrue: [
-	realNewOrigin := 0
-    ].
-
-    changed := (realNewHeight ~= thumbHeight) or:[realNewOrigin ~= thumbOrigin].
-    (changed or:[thumbFrame isNil]) ifTrue:[
-	old := self absFromPercent:thumbOrigin.
-	new := self absFromPercent:realNewOrigin.
-	changed := old ~~ new.
-	changed ifFalse:[
-	    old := self absFromPercent:thumbHeight.
-	    new := self absFromPercent:realNewHeight.
-	    changed := (old ~~ new)
-	].
-	(changed or:[thumbFrame isNil]) ifTrue:[
-	    thumbOrigin := realNewOrigin.
-	    thumbHeight := realNewHeight.
-
-	    (DefaultFullViewBackground notNil
-	    and:[DefaultViewBackground notNil
-	    and:[DefaultFullViewBackground ~~ DefaultViewBackground]]) ifTrue:[
-		realNewHeight >= 100 ifTrue:[
-		    nBg := DefaultFullViewBackground.
-		] ifFalse:[
-		    nBg := DefaultViewBackground
-		].
-		nBg := nBg on:device.
-		nBg ~~ viewBackground ifTrue:[
-		    self viewBackground:nBg.
-		    shown ifTrue:[self clear].
-		]
+e:[
+	    oldFrame := thumbFrame.
+	    self computeThumbFrame.
+	    (thumbHeight = 100) ifTrue:[
+		"/ full: don't draw
+		^ self
 	    ].
 
-	    shown ifTrue:[
-		thumbFrame notNil ifTrue:[
-		    self drawThumbBackgroundInX:(thumbFrame left)
-					      y:(thumbFrame top) 
-					  width:(thumbFrame width) 
-					 height:(thumbFrame height).
+	    (thumbFrame ~~ oldFrame) ifTrue:[
+		oldFrame isNil ifTrue:[
+		    self drawThumb.
+		    ^ self
 		].
-		self computeThumbFrame.
-		self drawThumb
-	    ] ifFalse:[
-		thumbFrame := nil
-	    ]
-	]
-    ]
-! !
-
-!Scroller methodsFor:'accessing-behavior'!
-
-action:aBlock
-    "for protocol compatibility; same as scrollAction:"
-
-    self scrollAction:aBlock
-!
-
-asynchronousOperation
-    "set scroll-mode to be asynchronous - scroll action is performed after
-     scrolling, when mouse-button is finally released"
-     
-    synchronousOperation := false
-!
+		tH := thumbFrame height.
+		tW := thumbFrame width.
 
-scrollAction
-    "answer the scroll action block"
-
-    ^ scrollAction
-!
-
-scrollAction:aBlock
-    "set the scroll action, aBlock which is evaluated when scrolled"
-
-    scrollAction := aBlock
-!
+		oldTop := oldFrame top.
+		oldBot := oldTop + tH.
+		oldLeft := oldFrame left.
+		oldRight := oldLeft + tW.
 
-scrollDownAction:aBlock
-    "ignored -
-     but implemented, so that scroller can be used in place of a scrollbar"
-!
+		thumbTop := thumbFrame top.
+		thumbBot := thumbTop + tH.
+		thumbLeft := thumbFrame left.
+		thumbRight := thumbLeft + tW.
 
-scrollUpAction:aBlock
-    "ignored -
-     but implemented, so that scroller can be used in place of a scrollbar"
-!
-
-synchronousOperation
-    "set scroll-mode to be synchronous - scroll action is performed for 
-     every movement of thumb"
-     
-    synchronousOperation := true
-! !
-
-!Scroller methodsFor:'accessing-look'!
+		needFullDraw := self exposeEventPending
+				or:[((orientation == #vertical) and:[oldBot >= height])
+				or:[((orientation ~~ #vertical) and:[oldRight >= width])]].
 
-is3D
-    styleSheet name = #mswindows ifTrue:[^ true].
-    ^ super is3D
-!
-
-orientation 
-    "return the scrollers orientation (#vertical or #horizontal)"
-
-    ^ orientation
-!
-
-thumbColor
-    "return the thumbs color"
-
-    ^ thumbColor
-!
-
-thumbColor:aColor
-    "change the color of the thumb"
-
-    thumbColor := aColor on:device.
-    (styleSheet name ~~ #normal) ifTrue:[
-	thumbShadowColor := aColor darkened on:device.
-	thumbLightColor := aColor lightened on:device.
-	thumbHalfShadowColor := thumbShadowColor darkened on:device.
-	thumbHalfLightColor := thumbLightColor lightened on:device.
-    ].
-    shown ifTrue:[
-	self redraw
-    ]
-! !
-
-!Scroller methodsFor:'drawing'!
+		needFullDraw ifTrue:[
+		    "
+		     cannot copy since thumb was below the end
+		     or may be not available for the copy
+		    "
+		    (orientation == #vertical) ifTrue:[
+			self drawThumbBackgroundInX:thumbLeft y:oldTop
+					      width:tW height:(height - oldTop).
+		    ] ifFalse:[
+			self drawThumbBackgroundInX:oldLeft y:thumbTop
+					      width:(width - oldLeft) height:tH.
+		    ].
+		    self drawThumb.
+		    ^ self
+		].
 
-drawHandleFormAtX:x y:y
-    thumbShadowColor := thumbShadowColor on:device.
-    thumbLightColor := thumbLightColor on:device.
-
-    self paint:thumbShadowColor.
-    self displayForm:shadowForm x:x y:y.
-    self paint:thumbLightColor.
-    self displayForm:lightForm x:x y:y.
-!
-
-drawThumb
-    "draw the thumb"
-
-    |handleX handleY l t 
-     w "{ Class: SmallInteger }"
-     h "{ Class: SmallInteger }"
-     x "{ Class: SmallInteger }"
-     y "{ Class: SmallInteger }"
-     mm xL xR yT yB color1 color2|
-
-    (thumbHeight >= 100) ifTrue:[^ self].
-    orientation == #vertical ifTrue:[
-	thumbFrame height >= height ifTrue:[^ self].
-    ] ifFalse:[
-	thumbFrame width >= width ifTrue:[^ self].
-    ].
-
-    l := thumbFrame left.
-    t := thumbFrame top.
-    w := thumbFrame width.
-    h := thumbFrame height.
-    self paint:thumbColor.
-    self fillRectangleX:l y:t width:w-1 height:h.
+		self catchExpose.
+		"
+		 copy the thumbs pixels
+		"
+		(orientation == #vertical) ifTrue:[
+		    self copyFrom:self x:thumbLeft y:oldTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		] ifFalse:[
+		    self copyFrom:self x:oldLeft y:thumbTop
+				     toX:thumbLeft y:thumbTop
+				   width:tW height:tH.
+		].
 
-    thumbLevel == 0 ifTrue:[
-	thumbFrameColor notNil ifTrue:[
-	    self paint:thumbFrameColor.
-	    self displayRectangle:thumbFrame.
-	].
-	^ self
-    ].
-
-    "what a kludge - must be a parameter to drawEdge..."
-    self drawEdgesForX:l y:t width:w height:h level:thumbLevel
-		shadow:thumbShadowColor light:thumbLightColor
-		halfShadow:thumbHalfShadowColor halfLight:thumbHalfLightColor
-		style:thumbEdgeStyle.
-
-    thumbFrameColor notNil ifTrue:[
-	self paint:thumbFrameColor.
-	orientation == #vertical ifTrue:[
-	    self displayRectangleX:l y:t width:w"-1" height:h.
+		"
+		 clear some of the previous thumbs area to background
+		"
+		(orientation == #vertical) ifTrue:[
+		    bgLeft := thumbLeft.
+		    bgWidth := tW.
+		    oldTop > thumbTop ifTrue:[
+			delta := oldTop - thumbTop.
+			oldTop > thumbBot ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := thumbBot.
+			    bgHeight := delta
+			]
+		    ] ifFalse:[
+			delta := thumbTop - oldTop.
+			oldBot < thumbTop ifTrue:[
+			    bgTop := oldTop.
+			    bgHeight := tH + 1
+			] ifFalse:[
+			    bgTop := oldTop.
+			    bgHeight := delta
+			]
+		    ].
+		] ifFalse:[
+		    bgTop := thumbTop.
+		    bgHeight := tH.
+		    oldLeft > thumbLeft ifTrue:[
+			delta := oldLeft - thumbLeft.
+			oldLeft > thumbRight ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := thumbRight.
+			    bgWidth := delta.
+			]
+		    ] ifFalse:[
+			delta := thumbLeft - oldLeft.
+			oldRight < thumbLeft ifTrue:[
+			    bgLeft := oldLeft.
+			    bgWidth := tW + 1.
+			] ifFalse:[
+			    bgLeft := oldLeft.
+			    bgWidth := delta.
+			]
+		    ].
+		].
+		self drawThumbBackgroundInX:bgLeft y:bgTop width:bgWidth height:bgHeight.
+		self waitForExpose
+	    ]
 	] ifFalse:[
-	    self displayRectangleX:l y:t width:w height:h"-1".
-	]
-    ].
-
-    (tallyLevel == 0 or:[tallyMarks == 0]) ifTrue:[
-	shadowForm notNil ifTrue:[
-	    handleX := l + ((w - 8) // 2).
-	    handleY := t + ((h - 8) // 2).
-	    self drawHandleFormAtX:handleX y:handleY
-	].
-	^ self
-    ].
-
-    "iris style - draw tallys"
-
-    tallyLevel > 0 ifTrue:[
-	color1 := thumbLightColor.
-	color2 := thumbShadowColor.
-    ] ifFalse:[
-	color1 := thumbShadowColor.
-	color2 := thumbLightColor.
-    ].
-
-    "draw tally marks"
-
-    (orientation == #vertical) ifTrue:[
-	self paint:color1.
-	y := t + (h // 2) - 1.
-	xL := l + thumbLevel - 1.
-	xR := l + w - thumbLevel "+ 1".
-	self displayLineFromX:xL y:y toX:xR y:y.
-	y := y + 1.
-	self paint:color2.
-	self displayLineFromX:xL y:y toX:xR y:y.
-
-	tallyMarks > 1 ifTrue:[
-	    "dont draw other marks if there is not enough space"
-
-	    mm := device verticalPixelPerMillimeter rounded.
-	    h > (mm * (tallyMarks * 2)) ifTrue:[
-		y := y - 1 - mm.
-		self paint:color1.
-		self displayLineFromX:xL y:y toX:xR y:y.
-		y := y + 1.
-		self paint:color2.
-		self displayLineFromX:xL y:y toX:xR y:y.
-
-		y := y - 1 + mm + mm.
-		self paint:color1.
-		self displayLineFromX:xL y:y toX:xR y:y.
-		y := y + 1.
-		self paint:color2.
-		self displayLineFromX:xL y:y toX:xR y:y
-	    ]
-	]
-    ] ifFalse:[
-	x := l + (w // 2) - 1.
-	yT := t + thumbLevel - 1.
-	yB := t + h - thumbLevel "+ 1".
-	self paint:color1.
-	self displayLineFromX:x y:yT toX:x y:yB.
-	self paint:color2.
-	x := x + 1.
-	self displayLineFromX:x y:yT toX:x y:yB.
-
-	tallyMarks > 1 ifTrue:[
-	    "dont draw other marks if there is not enough space"
-
-	    mm := device horizontalPixelPerMillimeter rounded.
-	    w > (mm * (tallyMarks * 2)) ifTrue:[
-		x := x - 1 - mm.
-		self paint:color1.
-		self displayLineFromX:x y:yT toX:x y:yB.
-		x := x + 1.
-		self paint:color2.
-		self displayLineFromX:x y:yT toX:x y:yB.
-
-		x := x - 1 + mm + mm.
-		self paint:color1.
-		self displayLineFromX:x y:yT toX:x y:yB.
-		x := x + 1.
-		self paint:color2.
-		self displayLineFromX:x y:yT toX:x y:yB
-	    ]
-	]
-    ]
-!
-
-drawThumbBackgroundInX:x y:y width:w height:h
-    "draw part of the thumbs background; defined as a separate
-     method, to allow drawing of arbitrary patterns under thumb 
-     (see ColorSlider)."
-
-    shown ifTrue:[
-	self clearRectangleX:x y:y width:w height:h.
-	frameBeforeMove notNil ifTrue:[
-	    self clippedTo:(Rectangle left:x top:y width:w height:h) do:[
-		|gX gY gW gH|
-
-		gX := frameBeforeMove left.
-		gY := frameBeforeMove top.
-		gW := frameBeforeMove width.
-		gH := frameBeforeMove height.
-                
-		ghostColor notNil ifTrue:[
-		    self fillRectangle:frameBeforeMove with:ghostColor.
-		].
-		(ghostLevel ~~ 0) ifTrue:[
-		    self drawEdgesForX:gX y:gY width:gW height:gH level:ghostLevel
-		].
-		ghostFrameColor notNil ifTrue:[
-		    self paint:ghostFrameColor.
-		    self displayRectangleX:gX y:gY width:gW height:gH
-		]
-	    ]
+	    thumbFrame := nil
 	]
     ]
 ! !
 
-!Scroller methodsFor:'event handling'!
-
-buttonMotion:state x:x y:y
-    "mouse-button was moved while pressed;
-     redraw thumb at its new position and, if scroll-mode is asynchronous, 
-     the scroll action is performed"
-
-    |pos curr limit prevOrigin newOrigin|
-
-    scrolling ifFalse: [^ self].              "should not happen"
-
-    frameBeforeMove isNil ifTrue:[
-	(ghostColor notNil 
-	or:[ghostFrameColor notNil
-	or:[ghostLevel ~~ 0]]) ifTrue:[
-	    frameBeforeMove := thumbFrame insetBy:1@1
-	]
-    ].
-
-    (orientation == #vertical) ifTrue:[
-	curr := y.
-	limit := height
-    ] ifFalse:[
-	curr := x.
-	limit := width
-    ].
-
-    (curr < 0) ifTrue:[                        "check against limits"
-	pos := 0
-    ] ifFalse:[
-	(curr > limit) ifTrue:[
-	    pos := limit
-	] ifFalse:[
-	    pos := curr
-	]
-    ].
-
-    prevOrigin := self thumbOrigin.
-    newOrigin := self percentFromAbs:(pos - pressOffset).
-    prevOrigin ~= newOrigin ifTrue:[
-	self thumbOrigin:newOrigin.
-
-	synchronousOperation ifTrue: [
-	    self tellOthers.
-	]
-    ]
-!
-
-buttonMultiPress:button x:x y:y
-    ^ self buttonPress:button x:x y:y
-!
-
-buttonPress:button x:x y:y
-    "button was pressed - if above thumb, page up; if below thumb, page down;
-     otherwise start scrolling"
-
-    |curr limit1 limit2|
-
-    shown ifFalse:[^ self].
-
-    (orientation == #vertical) ifTrue:[
-	curr := y.
-	limit1 := thumbFrame top.
-	limit2 := thumbFrame bottom
-    ] ifFalse:[
-	curr := x.
-	limit1 := thumbFrame left.
-	limit2 := thumbFrame right
-    ].
-
-    (curr < limit1) ifTrue:[
-	"page up/left"
-	self pageUp
-    ] ifFalse:[
-	(curr > limit2) ifTrue:[
-	    "page down/right"
-	    self pageDown
-	] ifFalse:[
-	    pressOffset := curr - limit1.
-	    scrolling := true
-	]
-    ]
-!
-
-buttonRelease:button x:x y:y
-    "mouse-button was released - if scroll-mode is asynchronous, the scroll
-     action is now performed"
-
-    |rect|
-
-    scrolling ifTrue:[
-        thumbFrame notNil ifTrue:[
-            frameBeforeMove notNil ifTrue:[
-                rect := frameBeforeMove.
-                frameBeforeMove := nil.
-                self drawThumbBackgroundInX:rect left
-                                          y:rect top
-                                      width:rect width 
-                                     height:rect height.
-                (rect intersects:thumbFrame) ifTrue:[
-                    self drawThumb
-                ]
-            ].
-
-            scrolling := false.
-            synchronousOperation ifFalse: [
-                self tellOthers.
-            ]
-        ]
-    ]
-
-    "Modified: 23.12.1995 / 12:42:25 / cg"
-!
-
-buttonShiftPress:button x:x y:y
-    "mouse-click with shift - jump to position"
-
-    |pos curr curr2 limit1 limit2|
-
-    (orientation == #vertical) ifTrue:[
-	curr := y.
-	curr2 := y - (thumbFrame height // 2).
-	limit1 := height.
-	limit2 := thumbFrame top
-    ] ifFalse:[
-	curr := x.
-	curr2 := x - (thumbFrame width // 2).
-	limit1 := width.
-	limit2 := thumbFrame left
-    ].
-
-    (curr2 < 0) ifTrue:[                        "check against limits"
-	pos := 0
-    ] ifFalse:[
-	(curr2 > limit1) ifTrue:[
-	    pos := limit1
-	] ifFalse:[
-	    pos := curr2
-	]
-    ].
-
-    frameBeforeMove := thumbFrame insetBy:1@1.
-
-    self thumbOrigin:(self percentFromAbs:pos).
-    self tellOthers.
-
-    (orientation == #vertical) ifTrue:[
-	limit2 := thumbFrame top
-    ] ifFalse:[
-	limit2 := thumbFrame left
-    ].
-    pressOffset := curr - limit2.
-    scrolling := true
-!
-
-redraw
-    "redraw"
-
-    self redrawX:0 y:0 width:width height:height.
-    self redrawEdges
-!
-
-redrawX:x y:y width:w height:h
-    shown ifTrue:[
-	thumbFrame isNil ifTrue:[self computeThumbFrame].
-	self drawThumbBackgroundInX:x y:y width:w height:h.
-	(y > thumbFrame bottom) ifTrue:[
-	    ^ self
-	].
-	((y + h) < thumbFrame top) ifTrue:[
-	    ^ self
-	].
-	self drawThumb
-    ]
-!
-
-sizeChanged:how
-    "size of scroller changed - recompute thumbs frame and redraw it"
-
-    |sensor|
-
-    shown ifTrue:[
-	self computeThumbFrame.
-	(sensor := self sensor) notNil ifTrue:[
-	    self redraw.
-	    sensor flushExposeEventsFor:self 
-	]
-    ]
-!
-
-update:something with:aParameter from:changedObject
-    "handle update from a model (if any)"
-
-    (changedObject == model 
-    "and:[something == aspectMsg]") ifTrue:[
-	self thumbOrigin:(model value).
-	^ self
-    ].
-    super update:something with:aParameter from:changedObject
-! !
-
-!Scroller methodsFor:'forced scroll'!
-
-pageDown
-    "page down/right"
-
-    self thumbOrigin:(thumbOrigin + thumbHeight).
-    self tellOthers
-!
-
-pageUp
-    "page up/left"
-
-    self thumbOrigin:(thumbOrigin - thumbHeight).
-    self tellOthers
-! !
-
-!Scroller methodsFor:'forwarding changed origin'!
-
-tellOthers
-    |org|
-
-    org := self thumbOrigin.
-    "
-     the ST/X way of notifying scrolls
-    "
-    scrollAction notNil ifTrue:[
-	scrollAction value:org 
-    ].
-    "
-     the ST-80 way of notifying scrolls
-    "
-    self sendChangeMessageWith:org.
-    self changed:#scrollerPosition.
-! !
-
-!Scroller methodsFor:'initialization'!
-
-computeInitialExtent
-    self extent:self preferredExtent
-!
-
-initCursor
-    "set the cursor - a hand"
-
-    cursor := Cursor hand
-!
-
-initStyle
-    "initialize style dep. stuff"
-
-    super initStyle.
-
-    DefaultViewBackground notNil ifTrue:[
-	viewBackground := DefaultViewBackground on:device.
-    ].
-    DefaultShadowColor notNil ifTrue:[
-	shadowColor := DefaultShadowColor on:device.
-    ].
-    DefaultLightColor notNil ifTrue:[
-	lightColor := DefaultLightColor on:device.
-    ].
-
-    tallyMarks := DefaultTallyMarks.
-    tallyLevel := DefaultTallyLevel.
-    DefaultLevel ~~ level ifTrue:[
-	self level:DefaultLevel.
-    ].
-    DefaultBorderWidth ~~ borderWidth ifTrue:[
-	self borderWidth:DefaultBorderWidth.
-    ].
-    thumbLevel := DefaultThumbLevel.
-    inset := DefaultInset.
-    fixThumbHeight := DefaultFixThumbHeight.
-    thumbEdgeStyle := DefaultEdgeStyle.
-
-    DefaultGhostColor notNil ifTrue:[
-	ghostColor := DefaultGhostColor on:device.
-    ].
-    DefaultGhostFrameColor notNil ifTrue:[
-	ghostFrameColor := DefaultGhostFrameColor on:device.
-    ].
-    ghostLevel := DefaultGhostLevel.
-
-    DefaultThumbFrameColor notNil ifTrue:[
-	thumbFrameColor := DefaultThumbFrameColor on:device.
-    ].
-    DefaultThumbShadowColor notNil ifTrue:[
-	thumbShadowColor := DefaultThumbShadowColor
-    ] ifFalse:[
-	thumbShadowColor := shadowColor.
-    ].
-    DefaultThumbLightColor notNil ifTrue:[
-	thumbLightColor := DefaultThumbLightColor
-    ] ifFalse:[
-	thumbLightColor := lightColor.
-    ].
-
-    thumbEdgeStyle notNil ifTrue:[
-	DefaultThumbHalfShadowColor notNil ifTrue:[
-	    thumbHalfShadowColor := DefaultThumbHalfShadowColor
-	].
-	DefaultThumbHalfLightColor notNil ifTrue:[
-	    thumbHalfLightColor := DefaultThumbHalfLightColor
-	].
-    ].
-
-    device hasGreyscales ifFalse:[
-	thumbEdgeStyle notNil ifTrue:[
-	    thumbHalfShadowColor := Color darkGrey.
-	    thumbHalfLightColor := White
-	].
-
-	thumbShadowColor := Black.
-"/        thumbLightColor := White.
+!Scroller methodsFor:'queries'!
 
-	styleSheet name = #motif ifTrue:[
-	    DefaultThumbColor isNil ifTrue:[
-		thumbColor := White .
-	    ].
-	]
-    ].
-
-    DefaultThumbColor notNil ifTrue:[
-	thumbColor := DefaultThumbColor on:device
-    ] ifFalse:[
-	thumbColor := White.
-	styleSheet name ~= #normal ifTrue:[
-	    device hasGreyscales ifFalse:[
-		thumbColor := Color grey
-	    ].
-	].
-    ].
-
-    thumbColor := thumbColor on:device.
-    thumbShadowColor notNil ifTrue:[
-	thumbShadowColor := thumbShadowColor on:device.
-    ].
-    thumbLightColor notNil ifTrue:[
-	thumbLightColor := thumbLightColor on:device.
-    ].
-    thumbHalfShadowColor notNil ifTrue:[
-	thumbHalfShadowColor := thumbHalfShadowColor on:device.
-    ].
-    thumbHalfLightColor notNil ifTrue:[
-	thumbHalfLightColor := thumbHalfLightColor on:device.
-    ].
-    thumbEdgeStyle notNil ifTrue:[
-	thumbHalfShadowColor isNil ifTrue:[
-	    thumbHalfShadowColor := thumbShadowColor lightened on:device
-	]
-    ].
-
-    styleSheet name = #next ifTrue:[
-	shadowForm := self class handleShadowFormOn:device.
-	lightForm := self class handleLightFormOn:device
-    ] ifFalse:[
-	shadowForm := lightForm := nil
-    ].
-
-    drawableId notNil ifTrue:[
-	self computeThumbFrame
-    ]
-!
-
-initialize
-    "initialize - setup instvars from defaults"
-
-    super initialize.
-    self computeInitialExtent.
-    orientation := #vertical.
-
-    scrolling := false.
-    synchronousOperation := true.
-
-    thumbOrigin := 0.
-    thumbHeight := 100.
-    thumbFrameSizeDifference := 0.
-
-    rangeStart := 0.
-    rangeEnd := 100.
-    rangeStep := nil.   "/ meaning: arbitrary precision
-"/    inset := 1.
-
-"/    self computeThumbFrame
-!
-
-realize
-    super realize.
-    model notNil ifTrue:[
-	self thumbOrigin:(model value).
-    ].
-! !
-
-!Scroller methodsFor:'private'!
-
-absFromPercent:percent
-    "given a percentage, compute number of pixels"
-
-    |fullSize|
-
-    (orientation == #vertical) ifTrue:[
-	fullSize := height
-    ] ifFalse:[
-	fullSize := width
-    ].
-"/    ^ ((percent * (fullSize - (margin * 2))) / 100) rounded
-"/ 20-apr-94
-
-    ^ ((percent * (fullSize - thumbFrameSizeDifference- (margin * 2))) / 100) rounded
-!
-
-computeThumbFrame
-    "compute the thumbs frame (a rectangle) whenever thumb is moved, 
-     changed height or the scrollers size has changed.
-     We take care, that the thumb will not become too small (i.e.
-     invisible or uncatchable).
-     Also, for mswindows style, its height/width is constant."
-
-    |newPos1 newPos2 newSize1 newSize2 nh nw ny nx 
-     computedSize minSz sz1 sz2|
-
-    "compute position & size"
-    newPos1 := (self absFromPercent:thumbOrigin) + margin.
-    newSize1 := computedSize := self absFromPercent:thumbHeight.
-    (orientation == #vertical) ifTrue:[
-	sz1 := height.
-	sz2 := width
-    ] ifFalse:[
-	sz1 := width.
-	sz2 := height
-    ].
-
-    "
-     do we have to adjust the computed size ?
-    "
-    newPos2 := margin + inset.     
-    newSize2 := sz2 - (2 * newPos2).
-"/    (style ~~ #normal) ifTrue:[
-    thumbLevel ~~ 0 ifTrue:[
-	"
-	 do not make thumb too small (for handle & to be catchable)
-	"
-	minSz := 10 + (2 * thumbLevel)
-    ] ifFalse:[
-	"
-	 do not make thumb too small (uncatchable)
-	"
-	minSz := 4
-    ].
-
-    (newSize1 < minSz) ifTrue:[
-	newSize1 := minSz.
-	thumbFrameSizeDifference := newSize1 - computedSize
-    ] ifFalse:[
-	thumbFrameSizeDifference := 0.
-    ].
-
-    fixThumbHeight ifTrue:[
-	"have a fix-size thumb (i.e. mswindows style)"
-
-	newSize1 := sz2 - (2 * inset).   "make it square"
-	thumbFrameSizeDifference := newSize1 - computedSize.
-    ].
-
-    "
-     oops - if height does not relect real visibible area, we have to adjust the origin
-    "
-    (thumbFrameSizeDifference == 0) ifFalse:[
-	newPos1 := (self absFromPercent:thumbOrigin) + margin.
-"/        newPos1 := ((thumbOrigin * (sz1 - thumbFrameSizeDifference - (margin * 2))) / 100) rounded + margin
-    ].
-
-    (orientation == #vertical) ifTrue:[
-	ny := newPos1.
-	nx := newPos2.
-	nh := newSize1.
-	nw := newSize2.
-	ny + nh + margin > height ifTrue:[
-	    ny := height - margin - nh
-	]
-    ] ifFalse:[
-	nx := newPos1.
-	ny := newPos2.
-	nw := newSize1.
-	nh := newSize2.
-	nx + nw + margin > width ifTrue:[
-	    nx := width - margin - nw
-	]
-    ].
-
-    "
-     do not create new Rectangle if its the same anyway
-    "
-    thumbFrame notNil ifTrue:[
-	(ny == thumbFrame top) ifTrue:[
-	  (nx == thumbFrame left) ifTrue:[
-	    (nh == thumbFrame height) ifTrue:[
-	      (nw == thumbFrame width) ifTrue:[ ^ self]
-	    ]
-	  ]
-	]
-    ].
-    thumbFrame := Rectangle left:nx top:ny width:nw height:nh
-!
-
-percentFromAbs:absValue
-    "given a number of pixels, compute percentage"
-
-    |fullSize val t|
-
-    (orientation == #vertical) ifTrue:[
-	fullSize := height
-    ] ifFalse:[
-	fullSize := width
-    ].
-
-    t := fullSize - thumbFrameSizeDifference - (margin * 2).
-    t = 0 ifTrue:[
-	"/ in rare cases, this happens ...
-	val := 0
-    ] ifFalse:[
-	val := absValue / t * (rangeEnd - rangeStart).
-    ].
-    val := val + rangeStart.
-
-    val < rangeStart ifTrue:[^ rangeStart].
-    val > rangeEnd ifTrue:[^ rangeEnd].
-    ^ val
-
-! !
-
-!Scroller methodsFor:'private-scrollView interface'!
-
-setThumbFor:aView
-    "get contents and size info from aView and adjust thumb"
-
-    |percentSize percentOrigin contentsSize contentsPosition viewsSize|
-
-    "
-     get the content's size
-    "
-    aView isNil ifTrue:[
-	contentsSize := 0
-    ] ifFalse:[
-	orientation == #vertical ifTrue:[
-	    contentsSize := aView heightOfContents.
-	    aView transformation notNil ifTrue:[
-		contentsSize := aView transformation applyScaleY:contentsSize.
-	    ].
-	] ifFalse:[
-	    contentsSize := aView widthOfContents.
-	    aView transformation notNil ifTrue:[
-		contentsSize := aView transformation applyScaleX:contentsSize.
-	    ].
-	]
-    ].
-
-    (contentsSize = 0) ifTrue:[
-	percentSize := 100.
-	percentOrigin := 100
-    ] ifFalse:[
-	(orientation == #vertical) ifTrue:[
-	    viewsSize := aView innerHeight.
-	    contentsPosition := aView yOriginOfContents.
-	] ifFalse:[
-	    viewsSize := aView innerWidth.
-	    contentsPosition := aView xOriginOfContents
-	].
-
-	percentSize := viewsSize * 100.0 / contentsSize.
-	percentOrigin := contentsPosition * 100.0 / contentsSize.
-	percentOrigin + percentSize > 100.0 ifTrue:[
-	    "actually showing stuff below contents of view"
-"
-	    contentsSize := contentsPosition + aView innerHeight.
-	    percentSize := viewsSize * 100.0 / contentsSize.
-	    percentOrigin := contentsPosition * 100.0 / contentsSize
-"
-	]
-    ].
-    (percentSize = thumbHeight) ifTrue:[
-	self thumbOrigin:percentOrigin
-    ] ifFalse:[
-	(percentOrigin = thumbOrigin) ifTrue:[
-	    self thumbHeight:percentSize
-	] ifFalse:[
-	    self thumbOrigin:percentOrigin thumbHeight:percentSize
-	]
-    ]
-!
-
-setThumbHeightFor:aView
-    "get contents and size info from aView and adjust thumb height"
-
-    |percent total viewsSize|
-
-    (orientation == #vertical) ifTrue:[
-	total := aView heightOfContents.
-	aView transformation notNil ifTrue:[
-	    total := aView transformation applyScaleY:total.
-	].
-    ] ifFalse:[
-	total := aView widthOfContents.
-	aView transformation notNil ifTrue:[
-	    total := aView transformation applyScaleX:total.
-	].
-    ].
-    (total = 0) ifTrue:[
-	percent := 100
-    ] ifFalse:[
-	viewsSize := (orientation == #vertical) ifTrue:[aView innerHeight]
-					   ifFalse:[aView innerWidth].
-	percent := viewsSize * 100.0 / total
-    ].
-    self thumbHeight:percent
-!
-
-setThumbOriginFor:aView
-    "get contents and size info from aView and adjust thumb origin"
-
-    |percent total contentsPosition|
-
-    (orientation == #vertical) ifTrue:[
-	total := aView heightOfContents.
-	aView transformation notNil ifTrue:[
-	    total := aView transformation applyScaleY:total.
-	].
-    ] ifFalse:[
-	total := aView widthOfContents.
-	aView transformation notNil ifTrue:[
-	    total := aView transformation applyScaleX:total.
+otal := aView transformation applyScaleX:total.
 	].
     ].
     (total = 0) ifTrue:[
@@ -1574,18 +2217,8 @@
     self thumbOrigin:percent
 ! !
 
-!Scroller methodsFor:'queries'!
-
-preferredExtent
-    |w h|
-
-    h := self class defaultExtent y.
-    w := (device horizontalPixelPerMillimeter asFloat * 6) rounded.
-    ^ w @ h.
-! !
-
 !Scroller class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libwidg/Scroller.st,v 1.36 1996-03-01 18:16:46 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libwidg/Scroller.st,v 1.37 1996-03-01 18:48:00 cg Exp $'
 ! !