diff -r 4faa8705e831 -r ad2a761d19cf Scroller.st
--- a/Scroller.st	Thu Apr 29 09:09:14 1999 +0200
+++ b/Scroller.st	Thu Apr 29 10:00:47 1999 +0200
@@ -1035,138 +1035,136 @@
      mm xL xR yT yB color1 color2|
 
     (thumbHeight >= 100) ifTrue:[^ self].
+
+    w := thumbFrame width.
+    h := thumbFrame height.
+
     orientation == #vertical ifTrue:[
-	thumbFrame height >= height ifTrue:[^ self].
+        h >= height ifTrue:[^ self].
     ] ifFalse:[
-	thumbFrame width >= width ifTrue:[^ self].
+        w >= width ifTrue:[^ self].
     ].
 
     l := thumbFrame left.
     t := thumbFrame top.
-    w := thumbFrame width.
-    h := thumbFrame height.
 
     self paint:(entered ifTrue:[thumbEnteredColor] ifFalse:[thumbColor]).
     self fillRectangleX:l y:t width:w-1 height:h.
 
     lvl := thumbLevel.
     scrolling ifTrue:[
-	lvl := thumbActiveLevel
+        lvl := thumbActiveLevel
     ].
 
     lvl == 0 ifTrue:[
-	thumbFrameColor notNil ifTrue:[
-	    self paint:thumbFrameColor.
-	    self displayRectangle:thumbFrame.
-	].
-	thumbImage notNil ifTrue:[
-	    thumbImage displayOn:self x:l y:t
-	].
-	^ self
+        thumbFrameColor notNil ifTrue:[
+            self paint:thumbFrameColor.
+            self displayRectangleX:l y:t width:w height:h.
+        ].
+        thumbImage notNil ifTrue:[
+            thumbImage displayOn:self x:l y:t
+        ].
+        ^ self
     ].
 
     self drawEdgesForX:l y:t width:w height:h level:lvl
-		shadow:thumbShadowColor light:thumbLightColor
-		halfShadow:thumbHalfShadowColor halfLight:thumbHalfLightColor
-		style:thumbEdgeStyle.
+                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".
-	]
+        self paint:thumbFrameColor.
+        self displayRectangleX:l y:t width:w height:h.
     ].
 
     thumbImage notNil ifTrue:[
-	thumbImage displayOn:self x:l y:t
+        thumbImage displayOn:self x:l y:t
     ].
 
     (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
+        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.
+        color1 := thumbLightColor.
+        color2 := thumbShadowColor.
     ] ifFalse:[
-	color1 := thumbShadowColor.
-	color2 := thumbLightColor.
+        color1 := thumbShadowColor.
+        color2 := thumbLightColor.
     ].
 
     "draw tally marks"
 
     (orientation == #vertical) ifTrue:[
-	self paint:color1.
-	y := t + (h // 2) - 1.
-	xL := l + lvl - 1.
-	xR := l + w - lvl "+ 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.
+        self paint:color1.
+        y := t + (h // 2) - 1.
+        xL := l + lvl - 1.
+        xR := l + w - lvl "+ 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"
+        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.
+            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
-	    ]
-	]
+                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 + lvl - 1.
-	yB := t + h - lvl "+ 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.
+        x := l + (w // 2) - 1.
+        yT := t + lvl - 1.
+        yB := t + h - lvl "+ 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"
+        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.
+            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
-	    ]
-	]
+                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
+            ]
+        ]
     ]
 
-    "Modified: / 12.5.1998 / 20:39:52 / cg"
+    "Modified: / 29.4.1999 / 09:35:52 / cg"
 !
 
 drawThumbBackgroundInX:x y:y width:w height:h
@@ -1613,7 +1611,7 @@
 sizeChanged:how
     "size of scroller changed - recompute thumbs frame and redraw it"
 
-    |oldThumbFrame|
+    |oldThumbFrame oldTop oldBot newTop newBot|
 
     oldThumbFrame := thumbFrame.
     thumbFrame := nil.
@@ -1624,12 +1622,31 @@
             thumbFrame = oldThumbFrame ifTrue:[
                 ^ self
             ].
+
+"/            "/ try to redraw as little as possible
+"/            orientation == #vertical ifTrue:[
+"/                oldTop := oldThumbFrame top.
+"/                oldBot := oldThumbFrame bottom.
+"/                newTop := thumbFrame top.
+"/                newBot := thumbFrame bottom.
+"/                newTop <= oldTop ifTrue:[
+"/                    newBot >= oldBot ifTrue:[
+"/                        self drawThumb.
+"/                        ^ self.
+"/                    ].
+"/                
+"/                ] ifFalse:[
+"/                    self drawThumbBackgroundInX:0 y:oldTop width:width height:(newTop-oldTop).
+"/                    self drawThumb.
+"/                ]
+"/            ]
+            self invalidate:(oldThumbFrame merge: thumbFrame).
+            ^ self.
         ].
-        "/ self clear.
         self invalidate
     ].
 
-    "Modified: / 7.11.1998 / 14:45:08 / cg"
+    "Modified: / 29.4.1999 / 09:43:12 / cg"
 !
 
 update:something with:aParameter from:changedObject
@@ -2321,5 +2338,5 @@
 !Scroller class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libwidg/Scroller.st,v 1.127 1999-04-28 17:52:56 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libwidg/Scroller.st,v 1.128 1999-04-29 08:00:47 cg Exp $'
 ! !