Index: sources/gui/qml/compounds/ValueAdjuster.qml
===================================================================
diff -u -r90f945668f1fff9ecb182b16ee33997cf515f52c -r56817942c7534dc34c2b0bce640534fa51671086
--- sources/gui/qml/compounds/ValueAdjuster.qml	(.../ValueAdjuster.qml)	(revision 90f945668f1fff9ecb182b16ee33997cf515f52c)
+++ sources/gui/qml/compounds/ValueAdjuster.qml	(.../ValueAdjuster.qml)	(revision 56817942c7534dc34c2b0bce640534fa51671086)
@@ -20,31 +20,25 @@
 import QtQuick.Controls 2.2
 
 Item { id: _root
-    property real   decimal     : 0
-    property real   minimum     : 0
-    property real   maximum     : 0
-    property real   value       : 0
+    property string extraText   : ""
+    property alias  value       : _rangedValue.rawValue
+    property alias  minimum     : _rangedValue.rawMin
+    property alias  maximum     : _rangedValue.rawMax
+    property alias  step        : _rangedValue.rawStep
+    property alias  decimal     : _rangedValue.precision
+    property alias  canOff      : _rangedValue.canOff
     property real   defaultValue: 0
-    property real   step        : 0
     property bool   isActive    : false
     property bool   editable    : true
-    property bool   canOff      : false
     property bool   canRefresh  : false
+    property alias  textColor   : _text.color
+    property bool   grabbed     : false
 
-    // fix floating-point precision issue
-    readonly property real stepVal  : Math.round(step       * 100) / 100
-    readonly property real minVal   : Math.round(minimum    * 100) / 100
-    readonly property real val      : Math.round(value      * 100) / 100
-
-    readonly property bool canIncrement  : isActive ? value  < maximum : true
-    readonly property bool canDecrement  : isActive ? canOff ? value > 0 :
-                                                               value > minimum : true
-
     signal didChange        (real vValue)
     signal didActiveChange  (bool vState)
 
     onIsActiveChanged             : {
-        if ( canRefresh )   { canRefresh = false; return;   }
+        if ( canRefresh )   { canRefresh = false; return    }
 
         if ( isActive )     { didChange(_root.defaultValue) }
     }
@@ -53,34 +47,17 @@
 
     function clear()        { didActiveChange(false)        }
 
-    function increment() {
-        let tValue = value
-        if ( ! isActive )   { didActiveChange(true); return;                    }
-
-        if ( canOff )       { tValue = val < minVal ? minVal : val + stepVal    }
-        else                { tValue += stepVal                                 }
-
-        didChange(tValue)
-
+    RangedValue { id: _rangedValue
+        objectName: "_rangedValue"
     }
 
-    function decrement(vValue) {
-        let tValue = value
-        if ( ! isActive )   { didActiveChange(true); return;            }
-
-        if ( canOff )       { tValue = val > minVal ? val - stepVal : 0 }
-        else                { tValue -= stepVal                         }
-
-        didChange(tValue)
-    }
-
     Text { id: _text
         anchors.centerIn: parent
         text            : _root.isActive ? _root.canOff ? _root.value === 0 ?
-                                                          "OFF" :
+                                                          qsTr("OFF") :
                                                           _root.value.toFixed( _root.decimal ) :
                                         _root.value.toFixed( _root.decimal ) : Variables.emptyEntry
-        color           : Colors.offWhite
+        color           : _rangedValue.isValueInRange || ! _root.isActive ? Colors.offWhite : Colors.red
         font.pixelSize  : Fonts.fontPixelValueControl
     }
 
@@ -125,10 +102,10 @@
         }
 
         MouseArea { id: _sliderMouseArea
-            property bool grabbed: false
 
             anchors.fill        : parent
             pressAndHoldInterval: 0
+            drag.axis           : Drag.XAxis      // only horizontal
 
             onClicked: {
                 if ( _root.editable ) { didActiveChange(true); focus = true }
@@ -137,30 +114,31 @@
             }
 
             onReleased: {
-                _sliderMouseArea.grabbed = true
-.                grabbed = false
+                _root.grabbed = false
                 _slider.opacity = 0
             }
 
             onPressAndHold: {
                 if ( _root.editable ) { didActiveChange(true); focus = true }
 
-                _sliderMouseArea.grabbed = true
+                _root.grabbed = true
             }
 
             onPositionChanged: {
-                if (grabbed) {
+                if (_root.grabbed) {
                     if ( _slider.opacity === 0 ) { _animator.start() }
 
-                    _slider.pos = Math.max(0, Math.min(1, mouse.x / parent.width))
-                    let raw =  _slider.from + _slider.pos * (_slider.to - _slider.from)
-                    let stepped = Math.round((raw - _slider.from) / _root.step) * _root.step + _slider.from
-                    didChange(stepped)
+                    if (_root.step != 0) {
+                        _slider.pos = Math.max(0, Math.min(1, mouse.x / parent.width))
+                        let raw =  _slider.from + _slider.pos * (_slider.to - _slider.from)
+                        let stepped = Math.round((raw - _slider.from) / _root.step) * _root.step + _slider.from
+                        didChange(stepped)
+                    }
                 }
             }
 
             onExited: {
-                if ( ! _sliderMouseArea.grabbed ) {
+                if ( ! _root.grabbed ) {
                     _animator.stop()
                     _slider.opacity = 0
                 }
@@ -172,7 +150,7 @@
             from    : 0
             to      : 1
             duration: 350
-            running : _sliderMouseArea.grabbed
+            running : _root.grabbed
         }
 
         Behavior on opacity { NumberAnimation { duration: 200 } }
@@ -185,11 +163,15 @@
             leftMargin      : Variables.defaultMargin
         }
         iconSize                : Variables.circleButtonDefaultDiameter
-        enabled                 : _root.canDecrement
+        enabled                 : _rangedValue.canDecrement
         visible                 : _root.editable
         iconImageSource         : enabled ? "qrc:/images/iArrowLeft" :
                                             "qrc:/images/iArrowLeftDisabled"
-        onClicked               : decrement()
+        onClicked               : {
+            if ( ! isActive ) { didActiveChange(true); return }
+
+            didChange(_rangedValue.decrementedValue())
+        }
     }
 
     IconButton { id: _rightArrow
@@ -199,10 +181,14 @@
             rightMargin     : Variables.defaultMargin
         }
         iconSize                : Variables.circleButtonDefaultDiameter
-        enabled                 : _root.canIncrement
+        enabled                 : _rangedValue.canIncrement
         visible                 : _root.editable
         iconImageSource         : enabled ? "qrc:/images/iArrowRight" :
                                             "qrc:/images/iArrowRightDisabled"
-        onClicked               : increment()
+        onClicked               : {
+            if ( ! isActive ) { didActiveChange(true); return }
+
+            didChange(_rangedValue.incrementedValue())
+        }
     }
 }