Merge branch 'kinetic-declarativeui' of git@scm.dev.nokia.troll.no:qt/kinetic into kinetic-declarativeui

2 files changed, 30 insertions, 2 deletions

diff --git a/src/declarative/util/qmlfollow.cpp b/src/declarative/util/qmlfollow.cpp
index 998166a..8e5ae69 100644
--- a/src/declarative/util/qmlfollow.cpp
+++ b/src/declarative/util/qmlfollow.cpp
@@ -55,7 +55,7 @@ class QmlFollowPrivate : public QObjectPrivate
 public:
     QmlFollowPrivate()
         : sourceValue(0), maxVelocity(0), lastTime(0)
-        , mass(1.0), spring(0.), damping(0.), velocity(0), enabled(true), mode(Track), clock(this) {}
+        , mass(1.0), spring(0.), damping(0.), velocity(0), epsilon(0.005), enabled(true), mode(Track), clock(this) {}
 
     QmlMetaProperty property;
     qreal currentValue;
@@ -67,6 +67,7 @@ public:
     qreal spring;
     qreal damping;
     qreal velocity;
+    qreal epsilon;
     bool enabled;
 
     enum Mode {
@@ -111,7 +112,7 @@ void QmlFollowPrivate::tick(int time)
             }
             currentValue += velocity * 10.0 / 1000.0;
         }
-        if (qAbs(velocity) < 0.5 && qAbs(sourceValue - currentValue) < 0.5) {
+        if (qAbs(velocity) < epsilon && qAbs(sourceValue - currentValue) < epsilon) {
             velocity = 0.0;
             currentValue = sourceValue;
             clock.stop();
@@ -300,6 +301,30 @@ void QmlFollow::setDamping(qreal damping)
     d->damping = damping;
 }
 
+
+/*!
+    \qmlproperty qreal Follow::epsilon
+    This property holds the spring epsilon
+
+    The epsilon is the rate and amount of change in the value which is close enough
+    to 0 to be considered equal to zero. This will depend on the usage of the value.
+    For pixel positions, 0.25 would suffice. For scale, 0.005 will suffice.
+
+    The default is 0.005. Small performance improvements can result in tuning this
+    value.
+*/
+qreal QmlFollow::epsilon() const
+{
+    Q_D(const QmlFollow);
+    return d->epsilon;
+}
+
+void QmlFollow::setEpsilon(qreal epsilon)
+{
+    Q_D(QmlFollow);
+    d->epsilon = epsilon;
+}
+
 /*!
     \qmlproperty qreal Follow::followValue
     The current value.
diff --git a/src/declarative/util/qmlfollow.h b/src/declarative/util/qmlfollow.h
index aac4c01..bd9363a 100644
--- a/src/declarative/util/qmlfollow.h
+++ b/src/declarative/util/qmlfollow.h
@@ -63,6 +63,7 @@ class Q_DECLARATIVE_EXPORT QmlFollow : public QmlPropertyValueSource,
     Q_PROPERTY(qreal velocity READ velocity WRITE setVelocity);
     Q_PROPERTY(qreal spring READ spring WRITE setSpring);
     Q_PROPERTY(qreal damping READ damping WRITE setDamping);
+    Q_PROPERTY(qreal epsilon READ epsilon WRITE setEpsilon);
     Q_PROPERTY(bool enabled READ enabled WRITE setEnabled);
 
     Q_PROPERTY(qreal followValue READ value NOTIFY valueChanged); 
@@ -80,6 +81,8 @@ public:
     void setSpring(qreal spring);
     qreal damping() const;
     void setDamping(qreal damping);
+    qreal epsilon() const;
+    void setEpsilon(qreal epsilon);
     bool enabled() const;
     void setEnabled(bool enabled);