--- a/DisplaySurface.st	Tue Dec 13 11:40:50 2016 +0100
+++ b/DisplaySurface.st	Fri Dec 16 13:37:31 2016 +0100
@@ -1028,6 +1028,8 @@
 
     |oldPaint org patternOffsetX patternOffsetY|
 
+    (w <= 0 or:[h <= 0]) ifTrue:[^ self].
+    
     gc isNil ifTrue:[
         "nothing to clear"
         ^ self.
@@ -1038,7 +1040,7 @@
         viewBackground isViewBackground ifTrue:[
             oldPaint := self paint.
             self 
-                paint:self background;
+                paint:gc background;
                 fillDeviceRectangleX:x y:y width:w height:h;
                 paint:oldPaint.
             viewBackground fillRectangleX:x y:y width:w height:h in:self.
@@ -1102,11 +1104,12 @@
 !
 
 fillDeviceRectangleWithPattern:aPixmap x:xIn y:yIn width:wIn height:hIn patternOffset:pattOffs
-    <resource: #obsolete>
     "fill a rectangular area with some pattern.
      A helper for devices which do not support pixmap drawing (i.e. win95).
      This is never invoked with X11 or Win-NT/XP/Vista systems.
-     Caller must ensure that aPixmap is really a form"
+     Caller must ensure that aPixmap is really a form.
+     CG: mhm it seems that XQuartz has a bug and also has problems doing this.
+         therefore it is actually not obsolete."
 
     |r b
      pW "{ Class: SmallInteger }"
@@ -1129,8 +1132,8 @@
 
     x := x max:0.
     y := y max:0.
-    r := (xIn + w - 1) min:(width - 1).
-    b := (yIn + h - 1) min:(height - 1).
+    r := (xIn + w) min:width.
+    b := (yIn + h) min:height.
 
     pW := aPixmap width.
     pH := aPixmap height.
@@ -1142,8 +1145,8 @@
         r := r min:oldClip right.
         b := b min:oldClip bottom.
     ].
-    w := r-x+1.
-    h := b-y+1.
+    w := r-x.
+    h := b-y.
 
     yR := (y // pH) * pH.
     yE := y+h.
@@ -1156,8 +1159,8 @@
     xR0 >= xE ifTrue:[^ self].
 
     aPixmap depth == 1 ifTrue:[
-        oldFg := self foreground.
-        oldBg := self background.
+        oldFg := gc foreground.
+        oldBg := gc background.
         (clrMap := aPixmap colorMap) notNil ifTrue:[
             bg := clrMap at:1.
             fg := clrMap at:2.
@@ -1165,7 +1168,7 @@
             bg := self whiteColor.
             fg := self blackColor.
         ].
-        self foreground:fg background:bg.
+        gc foreground:fg background:bg.
     ].
     self deviceClippingBounds:(Rectangle left:x top:y width:w height:h).
 
@@ -1191,7 +1194,7 @@
     ].
 
     oldFg notNil ifTrue:[
-        self foreground:oldFg background:oldBg.
+        gc foreground:oldFg background:oldBg.
     ].
     self deviceClippingBounds:oldClip.
 
@@ -1201,33 +1204,34 @@
 !
 
 fillRectangleWithPattern:aPixmap x:x y:y width:w height:h patternOffset:pattOffs
-    <resource: #obsolete>
     "fill a rectangular area with aPixmap.
      A helper for devices which do not support pixmap filling (i.e. win95 screens).
      This is never invoked with X11 or Win-NT/XP/Vista systems.
-     Caller must ensure that the aPixmap is really a form"
+     Caller must ensure that the aPixmap is really a form.
+     CG: mhm it seems that XQuartz has a bug and also has problems doing this.
+         therefore it is actually not obsolete."
 
     |pX pY nW nH currentTransformation|
 
     currentTransformation := gc transformation.
     currentTransformation notNil ifTrue:[
-	pX := currentTransformation applyToX:x.
-	pY := currentTransformation applyToY:y.
-	nW := currentTransformation applyScaleX:w.
-	nH := currentTransformation applyScaleY:h.
-	nW < 0 ifTrue:[
-	      nW := nW abs.
-	      pX := pX - nW.
-	].
-	nH < 0 ifTrue:[
-	      nH := nH abs.
-	      pY := pY - nH.
-	].
+        pX := currentTransformation applyToX:x.
+        pY := currentTransformation applyToY:y.
+        nW := currentTransformation applyScaleX:w.
+        nH := currentTransformation applyScaleY:h.
+        nW < 0 ifTrue:[
+              nW := nW abs.
+              pX := pX - nW.
+        ].
+        nH < 0 ifTrue:[
+              nH := nH abs.
+              pY := pY - nH.
+        ].
     ] ifFalse:[
-	pX := x.
-	pY := y.
-	nW := w.
-	nH := h.
+        pX := x.
+        pY := y.
+        nW := w.
+        nH := h.
     ].
     pX := pX rounded.
     pY := pY rounded.
@@ -1235,9 +1239,9 @@
     nH := nH rounded.
 
     self
-	fillDeviceRectangleWithPattern:aPixmap
-	x:pX y:pY width:nW height:nH
-	patternOffset:pattOffs
+        fillDeviceRectangleWithPattern:aPixmap
+        x:pX y:pY width:nW height:nH
+        patternOffset:pattOffs
 
     "Modified: 4.6.1996 / 17:58:49 / cg"
 !
@@ -2202,9 +2206,9 @@
         "/ i.e. poll for the event
         "/
         device isWindowsPlatform ifTrue:[
-            pollDelay := 1.
+            pollDelay := 0.5.
         ] ifFalse:[
-            pollDelay := 3.
+            pollDelay := 1.
         ].
         endPollTime := Timestamp now addSeconds:pollDelay.