Doc: Try to explain better when and how the easing curve is applied

Maybe not perfect, but it should be *better* at least.

Task-number: QTBUG-6623
Reviewed-by: Thierry

1 files changed, 7 insertions, 0 deletions

diff --git a/src/corelib/animation/qvariantanimation.cpp b/src/corelib/animation/qvariantanimation.cpp
index d529f67..bc0d35e 100644
--- a/src/corelib/animation/qvariantanimation.cpp
+++ b/src/corelib/animation/qvariantanimation.cpp
@@ -373,6 +373,13 @@ QVariantAnimation::~QVariantAnimation()
     Another example is QEasingCurve::InOutElastic, which provides an
     elastic effect on the values of the interpolated variant.
 
+    QVariantAnimation will use the QEasingCurve::valueForProgress() to
+    transform the "normalized progress" (currentTime / totalDuration)
+    of the animation into the effective progress actually
+    used by the animation. It is this effective progress that will be
+    the progress when interpolated() is called. Also, the steps in the
+    keyValues are referring to this effective progress.
+
     The easing curve is used with the interpolator, the interpolated()
     virtual function, the animation's duration, and iterationCount, to
     control how the current value changes as the animation progresses.